Soluble form of Fas and Fas ligand in serum and bronchoalveolar lavage fluid of individuals infected with human T-lymphotropic virus type 1.
Human T-lymphotropic virus type 1 (HTLV-1) carriers are known to develop pulmonary complications characterized by T-lymphocytic alveolitis. The aim of this study was to determine the profile and role of soluble Fas (sFas) and sFas ligand (sFasL) in the lung of asymptomatic HTLV-1 carriers. We measured sFas and sFasL levels in serum and bronchoalveolar lavage fluid (BALF) of 16 seropositive asymptomatic HTLV-1 carriers and 32 healthy subjects. The serum levels of both sFas and sFasL were significantly higher in HTLV-1 carriers than in the control. In BALF, the percentage of lymphocytes and CD4 positive T-cells, and the levels of sFasL were also significantly higher in asymptomatic carriers than the control, but there were no significant differences in sFas levels between the two groups. There was a significant correlation between BALF sFasL levels and serum sFasL levels and percentage of CD4 positive T-cells in BALF. Our results suggest that the increased levels of sFasL in the lung of asymptomatic HTLV-1 carriers are associated with accumulation of CD4 positive T-cells, and that resistance to apoptosis in HTLV-1 infected T-cells and overproduction of sFasL could contribute to T-lymphocytic alveolitis by down-regulating Fas-FasL mediated apoptosis.
Second Department of Internal Medicine, Nagasaki University School of Medicine, Sakamoto 1-7-1, Nagasaki 852-8501, Japan.
Noriho
N
Sakamoto
Hiroshi
H
Mukae
Takeshi
T
Fujii
Tomoyuki
T
Kakugawa
Hideyuki
H
Kaida
Jun-Ichi
J
Kadota
Shigeru
S
Kohno
D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay; D053222:Fas Ligand Protein; D005260:Female; D015490:HTLV-I Infections / Q000378:metabolism*; D015368:Human T-lymphotropic virus 1; D006801:Humans; D008171:Lung Diseases / Q000378:metabolism*; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis*; D008875:Middle Aged; D019014:fas Receptor / Q000032:analysis*
C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D019014:fas Receptor