Effects of some prostaglandins and leukotrienes on lymphocytes, monocytes and their activity in vitro

The effect of some prostaglandins (PGs) and leukotrienes (LTs) on lymphocytes and monocytes was tested in vitro. Overnight incubation with PGD2 reduces the expression of Leu-2 antigen (suppressor/cytotoxic phenotype) and of Fc receptors for IgG. PGA2, PGD2 and to a lesser extent PGE2 inhibit PHA reactivity of lymphocytes. LTB4 does not have any inhibitory activity. Preincubation of lymphocytes with PGD2 and PGE2 decreases their NK activity. LTB4, but not the PGs tested, stimulates monocyte metabolism as assessed by chemiluminescence.