Apoptosis of CD57+ and CD57- lymphocytes in the lung and blood of HIV-infected subjects.
Patients infected with HIV frequently have a CD8+ lymphocytic alveolitis consisting of HIV-specific CD8+CD57- cytotoxic T lymphocytes. However, in late stage disease, there is expansion of a CD8+CD57+ population with suppressive properties. We examined role of lymphocyte apoptosis in the expansion of the CD8+CD57+ lymphocytes in late stage HIV in the lung and blood compartment in human subjects. Fas was expressed on virtually all lung lymphocytes from HIV-infected and normal subjects. Fas ligand expression was increased in HIV infection in both CD8+CD57+ and CD8+CD57- lymphocytes, though a significantly greater percentage of CD8+CD57+ cells expressed this marker. CD8+CD57+ lymphocytes in normal and HIV-infected subjects underwent more apoptosis than CD8+CD57- cells. However, in late stage HIV infection, the percentage of CD8+CD57+ cells undergoing apoptosis declined. These data demonstrate that under normal conditions CD8+CD57+ cells appear destined to undergo programmed cell death. Expansion of suppressive CD8+CD57+ cells in the lungs of HIV-infected subjects with advanced disease may be due to the failure of this normal regulatory process.
Wood
Karen L
KL
Department of Medicine, Pulmonary Division, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Knox
Kenneth S
KS
Wang
Yana
Y
Day
Richard B
RB
Schnizlein-Bick
Carol
C
Twigg
Homer L
HL
D017209:Apoptosis / Q000276:immunology*; D018959:CD57 Antigens / Q000096:biosynthesis* / Q000097:blood; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D053222:Fas Ligand Protein; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D008168:Lung / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*; D048069:Tumor Necrosis Factors / Q000378:metabolism
D018959:CD57 Antigens; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D048069:Tumor Necrosis Factors