The Effects Of HIV Mutations On The Immune System

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all daughter cells during subsequent cell divisions. Then in one or more of
these daughter cells, the virus produces RNA copies of its genetic material.
These new HIV clones become covered with protein coats and leave the cell to
find other host cells where they can repeat the life cycle.
The Body Fights Back
As viruses begin to invade the body, a few are consumed by
macrophages, which seize their antigens and display them on their own
surfaces. Among millions of helper T cells circulating in the bloodstream, a
select few are programmed to "read" that antigen. Binding the macrophage, the
T cell becomes activated. Once activated, helper T cells begin to multiply.
They then stimulate the multiplication of those few killer T cells and B
cells that are sensitive to the invading viruses. As the number of B cells
increases, helper T cells signal them to start producing antibodies.
Meanwhile, some of the viruses have entered cells of the body - the only
place they are able to replicate. Killer T cells will sacrifice these cells
by chemically puncturing their membranes, letting the contents spill out,
thus disrupting the viral replication cycle. Antibodies then neutralize the
viruses by binding directly to their surfaces, preventing them from attacking
other cells. Additionally, they precipitate chemical reactions that actually
destroy the infected cells. As the infection is contained, suppresser T
cells halt the entire range of immune responses, preventing them from
spiraling out of control. Memory T and B cells are left in the blood and
lymphatic system, ready to move quickly should the same virus once again
invade the body.
HIV’s Life Cycle
In the initial stage of HIV infection, the virus colonizes helper
T cells, specifically CD4+ cells, and macrophages, while replicating itself relatively
unnoticed. As the amount of the virus soars, the number of helper cells
fal...