Spontaneous production of interferon-gamma and acid-labile interferon-alpha by subpopulations of human mononuclear cells.
A low-density subpopulation of normal human peripheral blood mononuclear leukocytes obtained by percoll gradients was found to produce significant levels (up to 10,000 units/ml) of interferon in the absence of an external inducer. The interferon (IFN) was characterized as a mixture of IFN-gamma (immune) and a pH-sensitive IFN-alpha by neutralization with specific antibodies, by lability to low pH, and by cross-reactivity on bovine cells. Significant levels of IFN were obtained only at high (greater than or equal to 5 X 10(6) cells/ml) cell densities. These levels were not affected by the presence of small T lymphocytes and sharply decreased with cell dilution in a nonlinear fashion. A release of IFN in the absence of an external inducer, indicates additional physiological roles besides its involvement in pathological conditions.
D002478:Cells, Cultured; D006801:Humans; D007370:Interferon Type I / Q000096:biosynthesis*; D007371:Interferon-gamma / Q000096:biosynthesis*; D008214:Lymphocytes / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology / Q000378:metabolism*
D007370:Interferon Type I; D007371:Interferon-gamma