How does your body get rid of viruses

[lazboy]

hey,
I need to do a Biology Report and need to know how your body gets rid of a virus or something else that is not meant to be in your body. Thanks in advance for the help

[cytochromeP]

There are 2 types of Immune Responses : Cell mediated and Humoral

1. Humoral: Here we have plasma cells secreting Anti-bodies specific to the pathogen. These antibodies complex with their specific antigens present on the pathogen and precipitate it out of the circulation. Such immune-complexes will then be cleared out completely with the help of 'complement' and phagocytic macrophages.

2. Cell-mediated: Here cytotoxic T lymphocytes are involved. These cells prevent the intracellular replication of viruses by releasing special chemicals called Interferons.

In general:

Viral infection, fungal infection => T cells
Bacterial infection => Plasma cells

Ref: 1. Immunology by Janus Kuby
2. Immunology by Tizzard

[MrMistery]

Ever wondered why your body can not fight the HIV virus? It is because it keeps changing it's proteic lare and the antibodies do not recognise it by the time they get there.
But i will find the cure for AIDS!

[biostudent84]

Offtopic: Did you know that the American KKK wants to throw everyone with AIDS into a form of concentration camp to keep it from spreading? Bleh...

Back on topic: Don't forget that you get a fever. A fever is a response to pathogens inside the human body. What it is trying to do is denature the proteins in the pathogens. Unfortunately, it only works if the denaturing tempureate of the pathogen is lower than that of the human body (estimated around 106* F).

Kyle

[Dr.Stein]

Humoral immune response only works to remove viral infection when the virus is still outside of the cell. When the virus already comes inside the cell, the virus-infected cell will process the viral peptides to express modified MHC-I (due to the present of foreign peptides of virus) on its surface to be recognized by CD8+ T-cell (CTL), in which it will kill the cell by cytotoxic activitiy. Also, the activated T-cell will release specific cytokine (interferon) that can induce cells to resist viral replication.

Why HIV cannot easily eradicated from cells? Because it infects immune cell (CD4+), which function to help B-cell for maturation to differentiate into plasma cells and memory cells. Now CD4+ even helps HIV to proliferate. It is terrible, cell that should protects our body from the infection now helps our enemy to kill ourself!

[victor]

That's a betrayer in our body...that's so complex Dr.Stein... all the thing that I know about immune system is the cell is using restrict endonucleasm enzyme to cut out virus's protein and making the virus non-active...

[chemistry_freako]

yea - restriction endonucleases are also involved sometimes in cell immunity defence =D

[Dr.Stein]

That's a betrayer in our body...that's so complex Dr.Stein... all the thing that I know about immune system is the cell is using restrict endonucleasm enzyme to cut out virus's protein and making the virus non-active...

Yes, it is only one of several mechanisms for cells to anticipate viral infection. Before the mechanism takes place, viral DNA is already fused to host's DNA and hijack it. Virus is much clever nowadays even the 'old' one: influenza, "the master of virus", still cannot be eradicated up to now like its colleague, the vaccinia

[victor]

Guess we must make a better molecular scissor....

[James]

Maybe nanotechnology will one day fight viruses for us.

[Dr.Stein]

Perhaps we need to give more education to lymphocytes and APCs to recognize all peptides from those clever viruses, so whatever and however they change such gene expression, our system will recognize it much better and faster

[victor]

Before Lymphocytes recognize the virus...the virus has already translate it's own RNA and make lymphocytes died...