title: Overexpression of Fas/CD95 and Fas-induced apoptosis in a patient with idiopathic CD4+ T lymphocytopenia.
abstract: The mechanisms of apoptosis have become better understood, in part with the discovery of Fas/CD95. We report the case of a patient characterized by a decreased CD4+ T cell count and an overexpression of Fas/CD95 resulting in apoptosis. A 54-year-old man presented with disseminated Mycobacterium xenopi infection. Analysis showed CD4+ T lymphopenia. Tests for human immunodeficiency virus (HIV) types 1 and 2 were negative. We compared the patient with eight healthy controls and five HIV-infected patients in terms of the expression of Fas/CD95 and Fas-mediated apoptosis of peripheral T lymphocytes. The percent of CD95+ cells in lymphocytes was 98% for the patient, and the mean percent of CD95+ cells in lymphocytes +/- SD for HIV-infected patients and healthy controls was 75% +/- 16% and 36% +/- 26%, respectively. The patient had a high level of spontaneous apoptosis, and apoptotic cells were all identified as being CD4+ T cells. Monoclonal antibodies to CD95 dramatically increased apoptosis of CD4+ T cells exclusively. CD4+ T lymphopenia observed in our patient correlated with an overexpression of Fas together with spontaneous and Fas-induced apoptosis.
authors.affiliation: Service des Maladies Infectieuses et Tropicales, Hôpital de l'Archet, Nice, France.
authors.forename: P M
authors.initials: PM
authors.lastname: Roger
authors.forename: G
authors.initials: G
authors.lastname: Bernard-Pomier
authors.forename: E
authors.initials: E
authors.lastname: Counillon
authors.forename: J P
authors.initials: JP
authors.lastname: Breittmayer
authors.forename: A
authors.initials: A
authors.lastname: Bernard
authors.forename: P
authors.initials: P
authors.lastname: Dellamonica
mesh_terms: D017209:Apoptosis / Q000276:immunology*; D018791:CD4 Lymphocyte Count; D015658:HIV Infections / Q000276:immunology; D006801:Humans; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000150:complications / Q000276:immunology; D019912:Mycobacterium xenopi; D015375:Receptors, Interleukin-2; D012016:Reference Values; D018344:T-Lymphocytopenia, Idiopathic CD4-Positive / Q000209:etiology / Q000276:immunology*; D019014:fas Receptor / Q000032:analysis / Q000276:immunology / Q000502:physiology
chemical_list: D015375:Receptors, Interleukin-2; D019014:fas Receptor