HIV final: The immune system

innate immunity

a non-specific immediate response

adaptive immunity

a specific, learned response that takes time to develop but has a memory

White blood cells

the soldiers of your immune system. There are many types 

B-Cells

produce antibodies, which are like smart bombs that lock onto specific invaders and tag them for destruction.

T-Cells

the special forces and commanders. They play. Critical role in the adaptive response.

Macrophages

the big eaters that engulf and destroy pathogens. They also act as lookouts. Presenting pieces of the invaded to T-cells.

A normal immune response

1) a pathogen enters the body

2) macrophages and other immune cells engulf the virus and present its unique proteins to CD4+ T-cells

3) the CD4+ T-cells recognize the threat and become activated

4) the activated CD4+ T-cells then signal to B-cells and CD8+ T-cells

5) b-cells start producing specific antibodies to fight the virus

6) CD8+ T-cells begin killing the infected cells

7) the immune system clears the infection, and some cells become “memory cells” to recognize the threat if it returns.

How HIV attacks the system

the strategy is to attack the commander of the army: the CD4+ T-Cell. Instead of attacking randomly, HIV specifically binding to the CD4 receptor on the surface of these vital cells. By infecting and destroying CD4+ T-cells. HIV cripples the entire immune system from the top down.

The slow decline

without enough CD4+ T-cells, the immune system can't effectively fight off invaders. Antibodies aren’t produced in sufficient numbers, killer T-cells aren’t properly activated.over time, the number of CD4+ T-cells in the body plummets, leading to severe immune deficiency. This leaves the body vulnerable to opportunistic infections – illnesses that a healthy immune system would easily fight off. This is the stage known as AIDS.