Helper/suppressor ratio

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Helper/suppressor ratio
Purposelaboratory test in which the percentage of CD3-positive lymphocytes in the blood positive for CD4

The T-Lymphocyte Helper/Suppressor Profile (Helper/Suppressor ratio, T4:T8 ratio, CD4:CD8 ratio) is a basic laboratory test in which the percentage of CD3-positive lymphocytes in the blood positive for CD4 (T helper cells) and CD8 (a class of regulatory T cells) are counted and compared. Normal values (95% confidence intervals) are approximately 30-60% CD4 and 10-30% CD8 depending on age (ratio 0.9 to 3.7 in adults). [1] One reason for abnormal results is the loss of CD4-positive cells to the human immunodeficiency virus (HIV) infection. The loss of CD4-positive cells to HIV infection can result in various distortions in the ratio, as in the initial period, production of HIV specific CD8 positive cells will cause a large fall in the ratio, but subsequent immunosuppression over time may lead to overall non production of immune cells and inversion of the ratio. It has been shown that the degree of inversion of this ratio in individuals on antiretroviral therapy is indicative of the age of the infection and independently predictive of mortality associated with non HIV events. [2] [3]

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Signs and symptoms of HIV/AIDS

The stages of HIV infection are acute infection, latency and AIDS. Acute infection lasts for several weeks and may include symptoms such as fever, swollen lymph nodes, inflammation of the throat, rash, muscle pain, malaise, and mouth and esophageal sores. The latency stage involves few or no symptoms and can last anywhere from two weeks to twenty years or more, depending on the individual. AIDS, the final stage of HIV infection, is defined by low CD4+ T cell counts, various opportunistic infections, cancers and other conditions.

HIV/AIDS research Field of immunology research

HIV/AIDS research includes all medical research that attempts to prevent, treat, or cure HIV/AIDS, as well as fundamental research about the nature of HIV as an infectious agent and AIDS as the disease caused by HIV.

The CD4+/CD8+ ratio is the ratio of T helper cells (with the surface marker CD4) to cytotoxic T cells (with the surface marker CD8). Both CD4+ and CD8+ T cells contain several subsets.

Epstein–Barr virus–associated lymphoproliferative diseases are a group of disorders in which one or more types of lymphoid cells, i.e. B cells, T cells, NK cells, and histiocytic-dendritic cells, are infected with the Epstein–Barr virus (EBV). This causes the infected cells to divide excessively, and is associated with the development of various non-cancerous, pre-cancerous, and cancerous lymphoproliferative disorders (LPDs). These LPDs include the well-known disorder occurring during the initial infection with the EBV, infectious mononucleosis, and the large number of subsequent disorders that may occur thereafter. The virus is usually involved in the development and/or progression of these LPDs although in some cases it may be an "innocent" bystander, i.e. present in, but not contributing to, the disease.

References

  1. "Labcorp test description". Archived from the original on 2007-08-09. Retrieved 2007-08-20.
  2. "Labcorp test description". Archived from the original on 2007-08-09. Retrieved 2007-08-20.
  3. Serrano-Villar S, Moreno S, Fuentes-Ferrer M, Sánchez-Marcos C, Avila M, Sainz T, de Villar NG, Fernández-Cruz A, Estrada V (2014). "The CD4:CD8 ratio is associated with markers of age-associated disease in virally suppressed HIV-infected patients with immunological recovery". HIV Medicine. 15 (1): 40–49. doi: 10.1111/hiv.12081 . PMID   24007533.