| After binding
with the CD4+ cell, the virus enters the
cell and, using an enzyme called reverse
transcriptase, merges its RNA with the
cell's genetic material (DNA). This
causes the DNA in the CD4+ cell to make
copies of HIV (replication). Another
enzyme called protease helps the new
viruses form. The new viruses then
"bud" off the infected cells
into the body, where they infect more
CD4+ cells. The presence of
the virus causes a person's immune system
to react by attacking the virus itself
and any HIV-infected cells. This process
results to formation of antibodies . A
person is said to be HIV-positive if
antibodies to the virus are detected by
tests, indicating infection.
As
HIV-infected CD4+ cells are destroyed or
impaired, the person's immune system
becomes less and less effective at
fighting infection and disease. The
person is said to be
"immunocompromised" or
"immunodeficient." Such people
are more likely to develop unusual
diseases called Opportunistic infections
that they would not get if their immune
systems were healthy.
As the
number of CD4+ cells decreases, the
person is more likely to get sick and
have more serious illnesses. When this is
the case, a person is usually diagnosed
with acquired immunodeficiency syndrome
(AIDS).
|
HIV enters T lymphocyte HIV uses cell's
own DNA and enzymes to copy its RNA
Enzymes
divide RNA to make new HIV
New HIV
then emerges out of the T lymphocyte
|
