Overexpression of Fas/CD95 and Fas-induced apoptosis in a patient with idiopathic CD4+ T lymphocytopenia.
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.
Roger
P M
PM
Service des Maladies Infectieuses et Tropicales, Hôpital de l'Archet, Nice, France.
Bernard-Pomier
G
G
Counillon
E
E
Breittmayer
J P
JP
Bernard
A
A
Dellamonica
P
P
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
D015375:Receptors, Interleukin-2; D019014:fas Receptor