HIV infection of T cells, however, eventually kills T cells, rendering the immune system powerless to stave off infections from microorganisms. HTLV infection of T cells changes the way the T cells work in the body, causing cancer. HTLV causes a fatal form of cancer called adult T cell leukemia. When T cells are infected by these retroviruses, the immune system is disabled and several serious illnesses result. T cells are the linchpin of the human immune response. Both HTLV and HIV attack human immune cells called T cells. Another human retrovirus, human T-cell leukemia virus (HTLV), was discovered three years prior to the discovery of HIV.
Human immunodeficiency virus (HIV), the virus that causes acquired immune deficiency syndrome ( AIDS), is a retrovirus. Although viruses are not normally affected by antibiotics, genes can be added to retroviruses that make them susceptible to specific antibiotics.Īs of 2006, researchers had discovered only a handful of retroviruses that infect humans.
Retroviruses are rendered safe by adding, mutating, or deleting viral genes so that the virus cannot reproduce after acting as a vector for the intended delivery of new genes. Many gene therapy treatments and experiments use disabled mouse retroviruses as a carrier (vector) to inject new genes into the host DNA. From the human perspective, the Retroviridae are the most immediate concern. Finally, members of the family Pseudoviridae infect yeast and insects. Members of the family Metaviridae infect fungi and insects. The HIV and HTLV types are members of the Retroviridae. The known retroviruses are classified into three families: Retroviridae, Metaviridae, and Pseudoviridae. The human T-cell leukemia virus (HTLV now two types are known), the first diseases causing retrovirus of humans, was discovered in 1981, followed two years later by the discovery of HIV. This concept, which was called reverse transcription, garnered Temin and David Baltimore (1938) a Nobel Prize in medicine or physiology in 1975. In the 1960s, Howard Temin (1934 –1994) proposed that retroviruses accomplished the replication of their genetic material by the aforementioned RNA-to-DNA route. This agent, later called Rous sarcoma virus, was the first retrovirus to be discovered. In 1911, Peyton Rous (1879 –1970) successfully isolated the agent that caused tumors in chickens. Retroviruses have been known for a long time. Retroviruses produce an enzyme known as reverse transcriptase that uses RNA as a template to manufacture DNA, which can then be permanently integrated into the DNA of the infected host cells. Retroviruses are viruses in which the genetic material consists of ribonucleic acid (RNA) instead of deoxyribonucleic acid (DNA).