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Acquired Immune Deficiency Syndrome (), suppresses the immune system related to infection with the human immunodeficiency virus (HIV). A person infected with HIV gradually loses immune function along with certain immune cells called CD4 T-lymphocytes or CD4 T-cell ....

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.... isolated what appeared to be a new human retrovirus—a special type of virus that reproduces differently from other viruses—from the lymph node of a man at risk for AIDS. Nearly simultaneously, scientists working in the laboratory of American research scientist Robert Gallo at the National Cancer Institute in Bethesda, Maryland, and a group headed by American virologist Jay Levy at the University of California at San Francisco isolated a retrovirus from people with AIDS and individuals having contact with people with AIDS. All three groups of scientists isolated what is now known as human immunodeficiency virus (HIV), the virus that causes AIDS. ....