The immune system

[maskman`]

i was wondering the wonder of the immune system and how all the things are kept in place so that we survive the infectious diseases, or that our children survive the infectious disease. we would have been dead had it not been for those antibiotic protein molecules which stop the bacteria from invading by various means. stoping them or destroying their walls. artificials antibiotics have helped mankind tremendously.

how does this take place so unconciously. this question has fueled my curiousity.?

[iNow]

One could equally marvel at the beauty of our heartbeat or the way our blood carries oxygen to all of the various parts of the body that need it. One could find wonder in the manner in which our nerve cells carry signals and allow us to move and to perceive. The auto-immune system is very similar.

 

I'm not sure what your specific question is. It sounds like you perhaps want to know more about the basic functioning of our immune systems?

 

 

[CharonY]

The immune system is a complex mechanism but it works on a completely different way than antibiotics. One of the main factor of our immune system is the recognition of foreign particles via antibodies. But the beauty behind it is that it does not require any knowledge of the particles that it will encounter. Instead we have a mechanisms that more or less randomly shuffles parts of the genes coding for the respective antibodies. That way we have a wide array of them that may (or may not) bind to stuff that enters our bodies (named antigens).

The whole system then is geared towards producing those antibodies that actually found something to bind to (e.g. parts of bacteria) and thus induces the production of more of its kind. A bit like evolution on the micro level.

[maskman`]

iNow yes the cardiovascular system and the nerve system are indeed wonders and the advances of chemistry and biiology has gifted us with a deeper perspective of understanding the grand design behind it.

yes i do , i want to know all about the basic functioning of the immune system.

[iNow]

Okay, well start reading, and then follow the references and read those.

 

http://en.wikipedia.org/wiki/Immune_system

[maskman`]

CharonY so basically a wide range of different antibodies by genes is produced, but only those antibodies which combine with the bacteria are produced more in more. so more antibodies that fit with the bacteria are found more in number in our body. natural selection it is indeed !

 

thx for the link iNow

[jp255]

 

CharonY so basically a wide range of different antibodies by genes is produced, but only those antibodies which combine with the bacteria are produced more in more. so more antibodies that fit with the bacteria are found more in number in our body. natural selection it is indeed !

Kind of. A wide array of antibodies will be produced in early B cell development, so we have a pool of cells capable of producing many many different antibodies with different epitopes (they will recognise different antigens). Production of more specific antibodies will occur during the adaptive immune system reponse to an invading pathogen. During this response a high affinity antibody (high affinity to the ivading pathogen's antigens) will be developed, and it is at this point when this specific antibody will become much more prelavent (temporarily).

 

A bit like evolution on the micro level.

 

 

A bit like evolution on the micro level.

The process is very much like evolution. Affinity maturation of antibodies by somatic hypermutation introduces variation. Then clonal selection of the highest affinity antibodies are selected, and then mass produced.

http://en.wikipedia.org/wiki/Affinity_maturation

http://en.wikipedia.org/wiki/Somatic_hypermutation

Those pages are interesting reads. I find it interesting that this process, with it's striking similarities to the process of evolution, evolved. The evolved trait itself is like a genetic algorithm.

 

Our immune system has evolved in a way that somewhat makes up for the vast differences in generation time between bacteria/virus and humans (minutes/hours vs years).

[maskman`]

quote

Our immune system has evolved in a way that somewhat makes up for
the vast differences in generation time between bacteria/virus and
humans (minutes/hours vs years).

 

i couldnt agree more. even before medicine was developed a average human could live up to 40 years. compared with the few hours of life span of bacteria.

 

quote During this response a high affinity antibody (high affinity to the
ivading pathogen's antigens) will be developed, and it is at this point
when this specific antibody will become much more prelavent
(temporarily).

so only when there is invasion will the lymphocytes be produced and will decrease in number when the number of pathogens have decrease or stopped invading.

 

 

however i do have one question

Affinity maturation of antibodies by somatic hypermutation introduces
variation. Then clonal selection of the highest affinity antibodies are
selected, and then mass produced.

does this mean the those antibodies which have the highest affinity survive and get passed on to the next generation?

[jp255]

 

so only when there is invasion will the lymphocytes be produced and will decrease in number when the number of pathogens have decrease or stopped invading.

Yes. I think the B cells will decline in number after the pathogen is killed off. A minority of those cells will become memory cells, which can respond quickly in the event of a future encounter with the same pathogen. This type of cell has a longer life span than a B cell, though I don't think they live forever otherwise there would be no need for booster jabs? I'm not totally sure on that but it would make sense.

 

 

 

does this mean the those antibodies which have the highest affinity survive and get passed on to the next generation?

It would have to be the memory cells which would have to be passed on for long term immunity, and this doesn't occur as far as I am aware. However, the mother can pass on antibodies via the placenta and also via breast milk. The antibodies passed from mother to child are important, and help to protect against infection.

http://www.ncbi.nlm.nih.gov/pubmed/12850343

http://www.ncbi.nlm.nih.gov/pubmed/22235228

 

Quoted from the first link:

"Maternal milk antibodies coat infant mucosal surfaces and some have a clear protective role. This has been studied extensively in infectious disease models such as rotavirus, E. coli, poliovirus, and retroviruses. In the rotavirus model, antirotaviral IgA can be detected in stools of breast-fed but not bottle-fed neonates. In a large cohort of lactating women infected with HIV-1 in Rwanda, anti-HIV milk antibodies of the IgG isotype were more frequently detected followed by secretory IgM. Surprisingly, anti-HIV-1 SIgA were less frequently found. The presence of milk SIgA at 15 days as well as the persistence of a SIgM response during the whole lactation period was associated with lower risk of HIV transmission from the mother to the infant. Recently, HIV-1 antibodies from maternal milk have been shown to block transcytosis in vitro in a monolayer enterocyte model. Among these antibodies, those directed against the ELDKWA epitope had higher neutralising activity than serum antibodies. In humans, milk excreted antibodies play a major role in protecting infants from infection by pathogens having a mucosal portal of entry."

 

I believe the protection received from the mother is temporary protection, most useful before the infant's immune system has developed properly.