| 00:00 | So I realized, uh because I was kind of a um last |
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| 00:06 | not last minute, but, you , you may not have had |
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| 00:10 | a lot of time to prepare for before, right? So I'm not |
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| 00:12 | how many r even went through this or you just gonna give it a |
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| 00:15 | over. That's fine. OK. we're gonna kind of begin with some |
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| 00:19 | the basics uh in a way it of things that apply to the whole |
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| 00:25 | . OK. So, uh of we're talking about. So the approach |
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| 00:30 | we're taking is um uh how does body fight disease, right? And |
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| 00:38 | , that immunity, then we look it from the other perspective of how |
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| 00:43 | the pathogen? So by that time have learned all the different ways in |
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| 00:49 | you can counteract infection, right? so then you look at, |
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| 00:54 | well, how does, obviously it's , right? We get sick, |
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| 00:59 | know. And so pathogens have ways get around all these different types of |
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| 01:04 | , right? So that's what we at in chapter 25. And that's |
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| 01:08 | , that's that um flip class So, um then we end, |
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| 01:14 | end of it is kind of putting all together really, you know, |
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| 01:17 | we look at different diseases and what mention. OK. Here, here |
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| 01:22 | some of the ways you, you disease in the context of, of |
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| 01:26 | particular disease and what, what the does to overcome it. So it |
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| 01:29 | of puts it all together at the . OK. So uh innate |
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| 01:35 | Um so we look at it in of one's own immunity, right? |
|
| 01:41 | you know, what is the state one's immune system? Of course, |
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| 01:45 | to, you know, how susceptible are, you know, what's your |
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| 01:49 | of resistance to disease? Ok. infection equal disease every single time? |
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| 01:56 | it, we are well aware by of this particular group, all |
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| 02:03 | what do we call those people? is a thematic characters, right? |
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| 02:10 | . So, no, that's not equal. Uh Coke, Robert Coke |
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| 02:16 | . But uh we learned that that's always the case. You, you |
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| 02:19 | um good for meningitis organism. I almost half the population carries it in |
|
| 02:27 | throat and they have no symptoms of . Ok? But when an outbreak |
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| 02:32 | , it's one of them. That's source of it. OK. So |
|
| 02:36 | so it's, that's true for many diseases that affect us. OK. |
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| 02:41 | Mumps and measles um among others cold , et cetera. Uh any |
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| 02:48 | Um So I kind of want to with this and why I mentioned it |
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| 02:54 | several times this semester in various So that's a anybody know what that |
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| 03:01 | from Chipotle? It's the burrito OK. So then we got avocado |
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| 03:08 | on top of there, we got like lettuce looks pretty good. |
|
| 03:15 | I'm hungry. Um So, but know that um from 2016, I |
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| 03:22 | it up 2016 2017 2018, 3 in a row was responsible for or |
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| 03:34 | . Ok. Um And that, course, coined the phrase you can't |
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| 03:39 | your coat without what is that equal ? Yeah, we call it |
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| 03:48 | so it got so bad. So looked this up and it says um |
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| 03:53 | from 2020 April. April 2020. uh three years ago, Chipotle agrees |
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| 03:59 | pay 25 million in federal fines, ? So no, from 2015 through |
|
| 04:07 | . So 15, 16, 74 of food borne illness, outbreaks, |
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| 04:13 | people sickened. Um I didn't say many people died. I'm sure there |
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| 04:18 | a few deaths. Um the uh Chipotle uh 641 people in Boston. |
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| 04:28 | . Ok. So um of course was it uh the the it was |
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| 04:35 | to um people handling the food and hygiene, improper sanitation, right? |
|
| 04:43 | surprising. So, when you think uh and it related to um the |
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| 04:48 | produce uh that they used and so learn this later, but you can |
|
| 04:55 | , you know, uh the farm the lettuce is grown and getting into |
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| 05:02 | mouth on that burrito bowl, How many hands that change that went |
|
| 05:07 | ? Right? Distributor, that people picking it, distributors, blah, |
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| 05:10 | , blah and anywhere along the you know, issue can happen. |
|
| 05:15 | , um, so what happens when have? Um, so there was |
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| 05:19 | person who actually came was one of victims of this, right? |
|
| 05:23 | um and I have some stuff underlying . Oh, well, there's some |
|
| 05:28 | I wanna point out. So you know, Rita Bowl on October |
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| 05:31 | became sickened. Four days later with diarrhea, uh common as we all |
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| 05:38 | common G I tract infection symptoms, ? Uh registered nurse began experiencing buddy |
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| 05:45 | , tell tale signs of an E infection. Stool sample tested positive for |
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| 05:50 | toxin producing E coli. So uh here for a second and all right |
|
| 05:56 | and symptoms. So every as we , right, every focused on infectious |
|
| 06:00 | , right? Disease is due to acquiring a micro, right? Um |
|
| 06:06 | so signs of syndromes. So every has associated signs and symptoms, |
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| 06:12 | Respiratory illness, you know, coughing in the throat, maybe these kind |
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| 06:17 | things. G I tract infections all similar dehydrated when I lost some water |
|
| 06:24 | of thing. And so uh with cause of disease, every, every |
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| 06:30 | disease has a cause ideological agent we it right. E coli, of |
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| 06:35 | , it's a pathogen, um duration severity of the disease just went on |
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| 06:41 | like uh typically for 10 days. stomach cramps, the fact that E |
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| 06:48 | has, I remember this one This is the oh 157, |
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| 06:52 | e coli uh virulence factors. Very . That's how pathogen causes disease, |
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| 06:58 | for it. Uh The ciga toxin one uh I think is another one |
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| 07:04 | attachment to your intestinal wall um and . And so it's what enable the |
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| 07:11 | to do what it can do. many of these are evolved in overcoming |
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| 07:18 | from your immune system. Ok? phase phase variation mechanism, right is |
|
| 07:23 | matter um reservoir, right? So source, right? So every infectious |
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| 07:33 | has a reservoir reservoir is the source the, don't worry so much about |
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| 07:38 | are kind of things we'll talk about 25. But um nevertheless, the |
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| 07:44 | source. And so for e coli particular one, the source is actually |
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| 07:49 | . Ok. Um We'll talk about later. How you know you go |
|
| 07:55 | , how do they get in my and how do they get it from |
|
| 07:57 | cow if everything less? Right? , there's that, that happens, |
|
| 08:01 | ? But um point is every infectious has a source and many times the |
|
| 08:07 | is a human, right? Like reservoir is a human mumps and |
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| 08:11 | reservoirs are human. But for other , rabies, those are uh generally |
|
| 08:18 | , um bats, very common Uh anyway, the point is uh |
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| 08:23 | are different types of reservoirs, They can be humans, they can |
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| 08:27 | animals, they can be water or or just the depends uh transmission. |
|
| 08:33 | , reservoir is one thing, But it has to get to |
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| 08:38 | right. Transmission of disease, various . Um food board, eating contaminated |
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| 08:44 | , right? Water could be a uh when you transmit right um uh |
|
| 08:53 | right through the air. Very very that's probably the most common rou of |
|
| 08:58 | is through the air, right? I think of all the respiratory |
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| 09:02 | right? Flu virus, the C , right? All those respiratory illnesses |
|
| 09:09 | uh airborne, right? And so uh so as we go through |
|
| 09:16 | again, this is kind of more 25 stuff, but that's the kind |
|
| 09:19 | at least get a preview of what do before we see what they we |
|
| 09:23 | do to them. OK. So , so the various factors the pathogen |
|
| 09:30 | , right? Various functions right? , I would say call this the |
|
| 09:36 | part of the infection here, Later part of the infection here, |
|
| 09:42 | ? So there is a kind of time element to it, right? |
|
| 09:44 | has to get in the host right? Maybe infect deeper into the |
|
| 09:50 | . These this is all things that time, but there's gonna be various |
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| 09:53 | for each one of these things. . And so really how deadly a |
|
| 10:00 | pathogen is relates to a number of of factors. OK. So, |
|
| 10:08 | so again, this, we just in the context of that woman who |
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| 10:14 | bowl, right? Uh pathology and is the process of causing disease, |
|
| 10:20 | ? So, infectious agents and their factors, et cetera, right? |
|
| 10:24 | we know that, you know, the infectious disease is, there's differences |
|
| 10:29 | terms of what they do to our , right, induces induce fever that |
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| 10:34 | dehydrated, whatever, right? Rash all, it all depends all all |
|
| 10:40 | . OK. So um all So we'll get into the different, |
|
| 10:45 | let's see what we get to. , these are some easy questions. |
|
| 10:48 | think you'll, these are slam OK? Just kind of think about |
|
| 10:54 | , which responds faster, right? we look at adaptive and they just |
|
| 10:59 | of the organization of the immune Ok. Just a second. |
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| 11:21 | OK. Let's count down 14, . Yeah, it's so think about |
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| 11:45 | there's a pathogen right here is uh , COVID, right? What does |
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| 11:53 | have to get through to cause Right. But how many layers, |
|
| 11:59 | . Well, COVID acquired through its transmission. So it's gonna go, |
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| 12:05 | know, right? Mucous membranes, ? That's a, that's gonna be |
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| 12:08 | physical barrier, right? Um Or it's something else maybe through the |
|
| 12:14 | skin is actually fairly impair, Yeah, you have natural openings and |
|
| 12:18 | . But um you know, airborne , right? So uh that's one |
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| 12:24 | and then you go deeper, Then you have different cell types that |
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| 12:27 | involved. Uh So let's just kind see the setup here. OK. |
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| 12:34 | we refer to the each type. I think that's, that's three lines |
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| 12:39 | defense, OK. Three lines of . First is your physical barriers, |
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| 12:46 | mucous membranes, right? And your is nonspecific. OK? Whatever is |
|
| 12:53 | there, the physical barrier will stop , right? It's not specifically certain |
|
| 12:57 | OK? Um But that community the . OK. That community relies on |
|
| 13:05 | . OK. Recognizing antigen, that's it's all about. OK. And |
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| 13:11 | a time limit to that, So we talked about that a little |
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| 13:15 | in the context of the phase variation , right? It takes time to |
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| 13:20 | uh seeing it's one thing then it buying to the engine, then it |
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| 13:26 | a a um response, right? something will happen as a result. |
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| 13:31 | all that takes time, right? is why in the immune system |
|
| 13:36 | of course, it's there much OK. So um first line |
|
| 13:42 | skin mucus membranes. But then remember both of these all right, skin |
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| 13:49 | mucus membranes are bacteria, right? micro biotic enhance those two things, |
|
| 13:59 | ? So their presence, believe their presence also is a deterrent to |
|
| 14:06 | . OK. Um Third layer. if you get past that, now |
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| 14:11 | get into more of what I call cell types and processes, processes kick |
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| 14:18 | processes like the information like um um , I call these things processed, |
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| 14:27 | involve chemical signals and step 12 and and these kind of things. |
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| 14:33 | So, and then you have things compliment, these are non cell based |
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| 14:39 | . OK? A compliment is um so um now once you get past |
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| 14:47 | , then you have your third life that's your T cells and B |
|
| 14:52 | OK. So they're the ones that involved in recognition, but you do |
|
| 14:58 | um uh cell types that will work both sides. OK? And that's |
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| 15:09 | that's your uh dendritic cells and So they have, they have um |
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| 15:18 | in both on both sides. These can actually work with um key |
|
| 15:26 | . OK? And so the B are the ones that produce antibodies. |
|
| 15:32 | . T cells have a little bit function in actuality, certain T cells |
|
| 15:38 | of control the whole process. Uh But that's what we'll talk about |
|
| 15:42 | . Um we'll talk a little bit it today and next time, but |
|
| 15:46 | chapter 25. OK. So um three levels right now, uh |
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| 15:55 | her, that immunity is all OK. Remember that can be what's |
|
| 16:03 | the periphery, right? Uh is it a gram gram out of |
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| 16:09 | , the molecule sticking out of A virus and like the protein |
|
| 16:14 | envelope proteins. Um uh a flagellum ? Things that are on the |
|
| 16:20 | So uh let's look at this Should be another easy one. All |
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| 16:29 | . So, among your family who do you think forgiving you, |
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| 16:37 | microbiota such a thunderous sound? All . This can down from 10. |
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| 17:17 | let's see. Let's see. of course. It's your mother. |
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| 17:22 | . Mother's day is coming up, your card. Thanks for the |
|
| 17:26 | OK. Um Among other things, . So um when you were |
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| 17:34 | obviously, it require me that microbiota birth. OK? Um Thereafter, |
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| 17:43 | acquiring other types, right? Because you're in the environment, right? |
|
| 17:50 | in the air, things you eat these are all gonna be contributing to |
|
| 17:55 | microbiota as you grow up. And so uh here this table is |
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| 18:01 | showing you and don't memorize this but it's just showing you kind of |
|
| 18:05 | numbers of these, right? So skin uh 10, 10,000 um 1000 |
|
| 18:18 | per mil, right? C F is what we call form a |
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| 18:22 | So basically think of C F U cell. So mil so the amounts |
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| 18:28 | per line, for example, uh the mouth, the uh millions of |
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| 18:37 | , the uh G U track, the G I track, right? |
|
| 18:41 | to the 11th per cubic centimeter. a humongous amount of bacteria in your |
|
| 18:48 | . OK. So uh now I saying, OK. Yeah, they're |
|
| 18:54 | everywhere, right? They're found everywhere your body well, they shouldn't be |
|
| 18:58 | , right? They shouldn't be floating in your brain, for example, |
|
| 19:01 | your heart, right. That signals signals some type of infection. |
|
| 19:05 | you know, aside from your vital , they are pretty much everywhere. |
|
| 19:10 | ? And they have their specialized micro environments. Ok. Uh They'll |
|
| 19:17 | . You'll have some certain types on skin you're not gonna have in your |
|
| 19:22 | . Ok. Many, you many will be aerobic, some |
|
| 19:26 | OK? Um But they create their little micro environment. So even in |
|
| 19:31 | mouth, your mouth, you'll have ropes in. There you go. |
|
| 19:35 | you're breathing air around them all the , right? Well, because they |
|
| 19:39 | , they're tiny, right? They hide mix and crannies in your, |
|
| 19:42 | your teeth, right? Your gums what not. That's how you get |
|
| 19:45 | cavities from bacteria. OK. So they ferment, right? And remember |
|
| 19:51 | need, you need to be anaerobic throw in for me. And so |
|
| 19:54 | , there's places that hide your mouth are anaerobic, you can't really create |
|
| 19:57 | OK. Uh environment. And so the skin typically is kind of salty |
|
| 20:03 | that attracts environment for staff, staff , can, can withstand higher salt |
|
| 20:10 | . So the point is all parts your body have these different micro environments |
|
| 20:14 | different types of, you know, terms of P H and so concentrations |
|
| 20:19 | salt concentrations, et cetera and the that inhabit those areas are very well |
|
| 20:24 | to them. Ok. As they be, as you want them to |
|
| 20:28 | , right? Because this principle of you learn, I, I assume |
|
| 20:32 | , by a one on the ecology there. Um, a criminal |
|
| 20:38 | Ok. Well, no, you heard it as competitive exclusion, but |
|
| 20:42 | mean, same thing, right? I think what's the textbook definition |
|
| 20:47 | No, two species can occupy the niche, right? Once you gotta |
|
| 20:52 | or be eliminated, right? And out. OK. And that's, |
|
| 20:57 | that principle is what helps keep, , helps keep pathogens out of your |
|
| 21:02 | or you have a well established microbiota something just to plop down and take |
|
| 21:10 | that can be very hard. When that can happen, what makes |
|
| 21:15 | easier for types to assert themselves and is this you're an antibiotic that can |
|
| 21:23 | the levels of, of your micro and that could open up opportunities for |
|
| 21:29 | . So that's one example, But you know, you're a healthy |
|
| 21:34 | , you're not on an inbox or , then you want that microbiota there |
|
| 21:39 | thing. OK? And so you look at these symbiosis, I'm sure |
|
| 21:44 | familiar with this. You, you um assign a zero plus or |
|
| 21:50 | to each member of the symbiosis, ? And so it is, and |
|
| 21:54 | of your microbiota falls into the first categories. OK? And mostly |
|
| 22:02 | but certainly those that are mutual. . So um and every day there's |
|
| 22:09 | new about one's microbio, right? everything from uh supplying you very effective |
|
| 22:17 | and amino acids to uh allowing you digest certain foods you otherwise couldn't because |
|
| 22:24 | can to immunological effects, positive immunological , um everything it could be like |
|
| 22:35 | effects as well. Like because remember those millions of micro micro microbes you |
|
| 22:40 | in the body that's millions of other you've got as well, so to |
|
| 22:47 | , right? And so the effects those, we understand some of |
|
| 22:51 | but there's a lot we don't And so um but think about how |
|
| 22:56 | they've been with us, right? have been evolving for six million |
|
| 23:00 | You've had that you had those bacteria humans, of course, the same |
|
| 23:04 | of time. So of course, gonna be some for the most |
|
| 23:08 | right? Um helping each other out . Um That's why I say you |
|
| 23:14 | , you can't be a germaphobe, ? You want those, you want |
|
| 23:18 | OK? Um The parasitic types, course, uh you can prior to |
|
| 23:25 | . Um obviously the parasites uh benefiting at your detriment. So, but |
|
| 23:32 | , uh commences mutual types. Those what pretty much make up your |
|
| 23:38 | but even those types, right? these guys, all right, every |
|
| 23:43 | in a while can become one of OK? Opportunistic. OK. Staff |
|
| 23:51 | a common example of this, You have staff primarily in your, |
|
| 23:56 | just memorize your nose skin. but if new areas open up to |
|
| 24:04 | , right, they can get beyond normal environment where they're more or less |
|
| 24:08 | a check and that's kind of where like to go. But if they |
|
| 24:12 | new entry to a cut or then you can have issues. |
|
| 24:18 | So now they're in areas they don't belong without the normal checks on them |
|
| 24:22 | they can proliferate uh not all but there's certain types that can do |
|
| 24:27 | . And so uh that's when a was once thought to be a mental |
|
| 24:34 | mutual type becomes an opportunistic pattern. . So uh that's so the primary |
|
| 24:41 | , right? Very different, The primary pathogen, if it's there |
|
| 24:47 | your body, it's not there just hang out, it's there to cause |
|
| 24:51 | , right? So primary pass something Ebola um anthrax um number of |
|
| 25:00 | right? So these are part of normal microbiota, obviously. OK. |
|
| 25:06 | , um all right. Any questions this? OK. All right. |
|
| 25:13 | let's look at, so it's gonna a little bit redundant because we look |
|
| 25:17 | physical barriers, we can look at in the context of being a physical |
|
| 25:23 | . But then also they have this function, which is being a chemical |
|
| 25:27 | because these physical barriers also produce secretions these secretions have chemicals that can have |
|
| 25:37 | activity. OK. So they kind have dual functions here. So, |
|
| 25:41 | the context of physical barrier, Skin obviously uh skin again is a |
|
| 25:48 | protective layer. OK. Um Thick remember it gives your cells stack on |
|
| 25:54 | of one another, right? It carrot, that kind of helps really |
|
| 25:59 | it, right? And so it's easy to penetrate through skin, |
|
| 26:06 | But the only way that happens is an insect vector, right? An |
|
| 26:10 | , uh what's not a virus, example, right. So the the |
|
| 26:14 | itself penetrating your skin through its uh . Um but you know, you |
|
| 26:22 | have natural openings obviously in your right? Pores, right? Sweat |
|
| 26:26 | , et cetera. That's where bacteria get in. Um when we talk |
|
| 26:30 | subcutaneous infection, that's usually introduced like a wound to some type of splinter |
|
| 26:37 | . What have you, then you get a subcutaneous infection um which can |
|
| 26:42 | be through a uh an opportunistic pathogen then arise this way. Ok. |
|
| 26:50 | , uh so mucous membrane. So are gonna be the line, |
|
| 26:54 | Your your body cas right? Not your nose and your throat and your |
|
| 27:00 | , right? These are all uh membranes. And so um that's a |
|
| 27:05 | as well. OK. And so uh have, for example, uh |
|
| 27:12 | and your mucous membranes have to be moist, right? Hence mucus, |
|
| 27:17 | ? That's what that mucus secretion is . And so uh uh tears and |
|
| 27:22 | , right? So saliva washing over teeth creates the contain, clean, |
|
| 27:27 | off your teeth of, of, microbes, um tears, you |
|
| 27:32 | you produce tears for the same function hairs in your nose and ears, |
|
| 27:39 | ? Um Help you keep stuff right? Trap dust, trap particles |
|
| 27:44 | whatnot. Um But especially this one escalator. Ok. So this is |
|
| 27:52 | your uh trachea or windpipe if you . Ok. Full of little hairs |
|
| 27:59 | are really moving, but it's that the mucous secretions that serve the |
|
| 28:06 | particulates get them out um when that's , right? Which, which |
|
| 28:11 | which it can be in, in illnesses. Ok. That stuff can |
|
| 28:17 | get into your lungs, right? often. Uh you might have |
|
| 28:22 | a uh primary infection due to a , right? Say a cold, |
|
| 28:27 | cold or flu in the course of infection, you become uh dehydrated, |
|
| 28:36 | ? Very common. What do what do you, what do you |
|
| 28:38 | told when, if you have a or a cold, drink fluids, |
|
| 28:41 | fluids, right? Because you get and if you, we normally don't |
|
| 28:45 | enough when it happens, it affects mucus um consistency. So it doesn't |
|
| 28:52 | as well. So it's not uncommon have a respiratory environmental infection that then |
|
| 28:58 | followed by a bacterial secondary infection. much worse because now it gets into |
|
| 29:02 | lungs. And um like pneumonia is , an example of that, |
|
| 29:08 | So the point is this is a important defense to keep functioning right? |
|
| 29:15 | in order to counteract a respiratory Ok. Um So other things you |
|
| 29:22 | go OK. What, how does have any use? Right. How |
|
| 29:24 | the ear wax? How does that me out? Well, it's it |
|
| 29:28 | , trapping stuff in there, Um Digestion, you constantly, your |
|
| 29:33 | are constantly about paralysis, right? material for your gut. Ok. |
|
| 29:39 | of course, covers the windpipe when swallow. So you don't get food |
|
| 29:43 | your uh trachea. So any these are all again, physical |
|
| 29:48 | but they all produce uh certain right? Chemical defenses, right? |
|
| 29:55 | , just the nature of the skin , very oily. Um although it |
|
| 30:00 | from person to person uh kind of . So these are environmental conditions that's |
|
| 30:05 | suitable for, for many microbial ok? Uh mucous membranes, |
|
| 30:12 | Saliva, gastric juice, low P and started by two um urine uh |
|
| 30:19 | slightly acidic. Um but a common is this, you see the multiple |
|
| 30:27 | Lyo design, right? So the apart pep, right? So it's |
|
| 30:32 | defense against bacteria. OK. Um defense and so defenses are produced by |
|
| 30:42 | lot of different cells in your right? They're just little short uh |
|
| 30:48 | um that basically acts like a it kind of goes into the membrane |
|
| 30:55 | leaks, right? And so there's of different types of defenses, hundreds |
|
| 31:00 | them, I think that various of cells produce uh your macrophages, your |
|
| 31:07 | um cells which are your, one your primary big acidic types have them |
|
| 31:11 | well as other types of cells in body. So um so just from |
|
| 31:16 | alone, physical barriers, chemical you get a lot of stuff already |
|
| 31:22 | can, that can counteract uh OK. Um Now one of those |
|
| 31:31 | fits in this category too, what call toll like receptors. So the |
|
| 31:35 | I think of these things is as alarm bells, let's the fire alarm |
|
| 31:40 | your body, right? Signaling something be going on here, infection |
|
| 31:46 | OK. And so of course, the way your body tells alert cells |
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| 31:53 | your body through chemicals, right? signals is how your body talks to |
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| 31:58 | cells, right? And so this uh it used to be called |
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| 32:05 | OK. Now it sounds weird, it became maps. OK. |
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| 32:12 | The maps. Uh oh to me it is is to me it kind |
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| 32:19 | signals an action basically. OK. they call them maps. OK. |
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| 32:23 | these are uh typically amino acid uh or sequences in these different types of |
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| 32:31 | of flagella, the cell wall, LP S layer, et cetera. |
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| 32:36 | amino acid sequences are recognized in these structures and they bind to a receptor |
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| 32:42 | that binding generates a chemical signal. . So you have types that external |
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| 32:51 | internal receptors, right? So your like receptors T L R S are |
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| 32:58 | the surface, right? The other are what we call nod like |
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| 33:04 | they're internal. So remember uh bobby , virus like a virus can infect |
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| 33:11 | be inside of a cell. So some of those things can be found |
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| 33:17 | by a nod like receptor and create effect. Ok. Um So here's |
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| 33:23 | example of pathogen, right? There's bacterial pathogen and the flagellum part of |
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| 33:31 | can act as a as a right? And internally. So say |
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| 33:38 | have a, so the way toxins is bacter toxins, they get inside |
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| 33:43 | cell and cause different effects. So in itself can also be an N |
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| 33:47 | . So can a viral infection, of those can, can uh bind |
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| 33:52 | these. And so whichever one it's to, it's gonna create this cascade |
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| 33:58 | them, right? Basically, the the production of different signals that ultimately |
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| 34:04 | lead to production of cytokines. And is something we'll, you'll hear time |
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| 34:09 | time again in this unit is cyto , cytokine site. So it's a |
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| 34:15 | term that describes a number of different which have various roles in fighting an |
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| 34:23 | . Ok. And those roles there are some, not all of |
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| 34:27 | , but some of the major So chemo attractive. So you have |
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| 34:32 | infection somewhere. You want to bring the relevant cells that can take care |
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| 34:37 | the infection to the site. So have to attract them and track them |
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| 34:41 | the certain chemicals. Another important function um basaltic factors. Ok? Especially |
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| 34:52 | . Ok. Your major cell pathogen fighters are neutrophils that are in |
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| 34:58 | blood neutrophils, right? They go then ingest, right? So your |
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| 35:06 | has like is full of like 70% your blood is is neutrophils. |
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| 35:12 | So they're of course, circulating in blood vessels. So what you need |
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| 35:18 | an infection, you need to get out of the blood vessels. |
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| 35:24 | To do the job. And so where vasoactive factors can they manipulate blood |
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| 35:30 | , making them more leaky, enable to come out, right? And |
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| 35:36 | so very important function. So we'll that in the inflammatory response, we'll |
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| 35:41 | about next time. Uh activating T activating macros, these are important infection |
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| 35:48 | . So, t cells will activate adaptive immune system. Let me get |
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| 35:53 | going. So, so, and are just 44 different types. There's |
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| 35:58 | more than that, each with slightly different roles, inducing fever for |
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| 36:04 | kind that do that. So very functions, all, all with the |
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| 36:08 | of, you know, in some or another counteracting an infection. |
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| 36:15 | Uh Basically telling other cells of the system to do different things to, |
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| 36:21 | overcome this infection. OK. And , um so again, it's the |
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| 36:25 | you hear a lot, you'll hear lot in intersection of and so, |
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| 36:30 | so let's look at this question. . This won't be too difficult. |
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| 36:37 | , you got the, uh, pictures. Wait, is there another |
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| 36:42 | here? Hold on. All Yeah, of course, we have |
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| 36:47 | , I think of it. All . So we got, uh, |
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| 36:51 | have trophy, the macrophage and at site don't have a picture of a |
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| 37:00 | . Yeah. If you're looking for cell of the adaptive immune system, |
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| 37:04 | a name, a general name for . Ok. Let's count down |
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| 37:59 | Um OK. See. Yeah, gonna be the sites of course. |
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| 38:10 | . So uh T cells, B that fit into the lymphocyte mode. |
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| 38:16 | . Um So we look at, we go from physical chemical barriers to |
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| 38:23 | second line even. So different cell , specific cell types. OK? |
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| 38:29 | So you take blood, of I'm sure you know this you can |
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| 38:33 | , right? You'll have a uh fraction and a uh uh fraction um |
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| 38:41 | set uh pellets. OK. And we got at the plasma which is |
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| 38:46 | protein, heavy blood plasma contains basically of protein. OK? Including |
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| 38:52 | complement and other um formed elements are cells. So erythrocytes, red blood |
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| 38:59 | , leucocytes, that's our focus Um And so the term granular site |
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| 39:06 | a granular site, all that refers is how it looks under a |
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| 39:11 | OK. Granular sites have very obvious in them. OK? A grano |
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| 39:19 | do not but it doesn't mean they have them. They're just not as |
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| 39:23 | and visible in the light microscope. really the only, that's the difference |
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| 39:27 | those two terms. OK. Um they look like under a microscope. |
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| 39:32 | . So neutrophils basophils Eoin, Um lymphocytes are in the a on |
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| 39:41 | side side. OK. So let's at some of these more closely |
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| 39:47 | So neutrophils primary big city type early the infection. OK. So early |
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| 39:55 | is a very, they have a kind of uh nucleus uh that we |
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| 40:02 | load different loads. It's all connected they appear as like lumps or |
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| 40:10 | single movie that they very characteristic in group. Um These are types that |
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| 40:17 | blood that is again early early in infection cycle. They're the primary ones |
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| 40:22 | the work. Ok. Um So are not about, they're much less |
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| 40:30 | in the cell in the blood, me. Um They, they often |
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| 40:36 | um antibodies sitting on top of Ok? And those antibodies will bind |
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| 40:44 | and that will create an effect in basophil. Basic basophils are about emitting |
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| 40:50 | . That's what they do. Um like histamine and others are part of |
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| 40:54 | inflammatory response will talk about that But they thing about really chemicals. |
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| 40:59 | you have allergies, these kind of overactive and that's when you get your |
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| 41:04 | watery eyes and, and, and these can be acidic but their function |
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| 41:18 | really with dealing large pathogens by I mean large could be multicellular |
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| 41:24 | right? You can have infectious agents are things like worms, right? |
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| 41:30 | so these tend to deal with those , ok? But again, they're |
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| 41:35 | heavily a toxin releaser, ok? Among the leucocyte, a, I |
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| 41:43 | say a grand you've got um monocytes typically are floating in the blood, |
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| 41:52 | then they exit and go into your tissue. Lymphatic tissue is kind of |
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| 41:59 | of it as a a it's in to your circulatory system, OK? |
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| 42:05 | a system of vessels, OK? you have lymphatic fluid going through |
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| 42:10 | We'll talk about that next time, that's where they develop into macrophages and |
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| 42:16 | cells. OK? In this lymphatic , um these have a role as |
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| 42:22 | mentioned in working with the adaptive immune . OK? A a function they |
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| 42:30 | is what's called antigen presentation. And it's that function that kind of |
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| 42:39 | them to the adaptive immune system, they work with cell to that |
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| 42:43 | OK. Again, we'll elaborate on later. But um the, the |
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| 42:50 | uh natural pillar cells are also a of lymphocyte um as well as T |
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| 42:58 | and B cells. OK. uh so you differentiate T cells and |
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| 43:05 | cell function in terms of what they , you gotta remember, um pathogens |
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| 43:14 | be of two types, they can their disease cause stuff completely outside cells |
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| 43:22 | exercise that right. Um Then there types that do not they go inside |
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| 43:30 | , the obvious example there of But you haven't learned this yet, |
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| 43:36 | you'll learn that there are also bacterial that can also go inside cells, |
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| 43:43 | for the purpose of replicating cells like virus does, but to hide |
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| 43:48 | hide out from the immune system and to penetrate deeper into your body. |
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| 43:56 | the meningitis organism typically sits on the , right on the um mucous |
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| 44:02 | OK. But then it gets into brain, right? So how does |
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| 44:07 | do that? Well, it has to get inside your different cells and |
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| 44:13 | to the brain. OK. So a type of intracellular pattern. |
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| 44:19 | Um So the point is that viruses definitely are of that inciter type |
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| 44:26 | so too can certain types of bacterial . OK? As we'll learn. |
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| 44:29 | right. So you have to have that will deal with both types. |
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| 44:36 | ? And um that works can work differently. OK. So you have |
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| 44:42 | cells that, that's kind of their to do that. And then B |
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| 44:46 | produce antibodies. So, antibodies, , which we always draws like these |
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| 44:51 | shaped structures, right? They recognize on this part of the antibody. |
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| 45:00 | . A G is short for OK. So then you have a |
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| 45:04 | here, they actually combined to a , right? But um the engine |
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| 45:10 | , this these only work outside the and anybody can't go inside of the |
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| 45:17 | . And interact with an manager. only work outside the cell. The |
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| 45:21 | cells are ways of dealing with uh that have been infected. OK. |
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| 45:26 | we'll see. All right. um the natural killer cells, |
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| 45:33 | So these are the type, they a type, they can recognize infected |
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| 45:38 | . OK. Remember it could be virus infected cell. How you |
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| 45:43 | how you gonna know that? Because not inside the cell being recognized, |
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| 45:47 | inside the cell hiding. So you to have a way to, to |
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| 45:50 | those type types of cells that are . Ok. Um Also some cancerous |
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| 45:58 | uh can be recognized by natural killer in. OK. It's actually an |
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| 46:04 | , has been an active area of is to take advantage of this, |
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| 46:10 | ? In terms of using it to with different types of cancers. |
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| 46:15 | Um OK. I don't, I not. We're gonna talk about these |
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| 46:22 | . All right. Any questions? how I'm gonna, that's what we're |
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| 46:26 | stop here today, folks. Pick up next time. Thanks. Have |
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| 46:31 | good weekend. Go |
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