Skip to main content

Why can a person with AIDS die from a simple infection?

AIDS is a syndrome that develops due to an individual's infection with human immunodeficiency virus (HIV).  This virus essentially inactivates the adaptive immune system of an individual of which it infects.  


The adaptive immune system consists of cell-mediated and antibody-mediated immunity.  Both branches require activation by helper T cells before they can actively combat pathogens that have infected the body.  Helper T cells, once they have been exposed to the antigens (cell surface markers) of a suspected pathogen, will activate both cytotoxic T cells and also B cells.


Cytotoxic T cells can help to combat infections by producing and using toxic chemicals to kill pathogens and white blood cells that have already engulfed pathogens.  B cells, once activated, differentiate into plasma cells which can then produce antibodies that are specific to the antigens of the pathogen that incited the immune response.  These antibodies bind to the antigens of the pathogens as they flow through the circulatory system and, when bound, activate the compliment system which leads to the destruction of the pathogens.  Memory cells are also made in both branches so that the immune system can remember pathogens to which it has been exposed.  This increases the speed to which it can respond to the same pathogens in the future.


The problem with HIV and AIDS is that the virus specifically targets and disrupts the function of helper T cells.  If helper T cells are no longer functioning and no longer able to activate cell-mediated and antibody-mediated branches of the immune system, these systems are no longer available to fight infections.  Populations of pathogens may be allowed to grow uncontrolled except for controls due to the innate immune system (which may not be enough) and potentially lead to the death of the individual.

Comments

Post a Comment

Popular posts from this blog

Is there a word/phrase for "unperformant"?

As a software engineer, I need to sometimes describe a piece of code as something that lacks performance or was not written with performance in mind. Example: This kind of coding style leads to unmaintainable and unperformant code. Based on my Google searches, this isn't a real word. What is the correct way to describe this? EDIT My usage of "performance" here is in regard to speed and efficiency. For example, the better the performance of code the faster the application runs. My question and example target the negative definition, which is in reference to preventing inefficient coding practices. Answer This kind of coding style leads to unmaintainable and unperformant code. In my opinion, reads more easily as: This coding style leads to unmaintainable and poorly performing code. The key to well-written documentation and reports lies in ease of understanding. Adding poorly understood words such as performant decreases that ease. In addressing the use of such a poorly ...
Post a Comment
Read more

Is 'efficate' a word in English?

I routinely hear the word "efficate" being used. For example, "The most powerful way to efficate a change in the system is to participate." I do not find entries for this word in common English dictionaries, but I do not have an unabridged dictionary. I have checked the OED (I'm not sure if it is considered unabridged), and it has no entry for "efficate". It does have an entry for "efficiate", which is used in the same way. Wordnik has an entry for "efficate" with over 1800 hits, thus providing some evidence for the frequency of use. I personally like the word and find the meaning very clear and obvious when others use it. If it's not currently an "officially documented" word, perhaps its continued use will result in it being better documented.
Post a Comment
Read more