In vitro of adenosine on lymphocytes and erythrocytes from horses with combined immunodeficiency (original) (raw)

1979, Journal of Clinical Investigation

of adenosine on the mitogenic response of' peripheral blood lymphocytes (PBL) and on the nucleotide pools of erythrocytes from normal horses, horses heterozygous for the combined immunodeficiency (CID) trait (carriers), and foals with CID was studied. When PBL from normal, carrier, and CID horses were stimulated by phytohemagglutinin (PHA), concanavalin A, or pokeweed mitogen, [3H]thymidine uptake was inhibited by adenosine (0.1 ,uM to 1.0 mM) in a dose-dependent manner. Adenosine (100 ,sM) mediated inhibition of [3H]thymidine uptake was prevented in both normal and carrier horse PBL by incubation with uridine. Uridine had no sparing effect on PBL from horses with CID. Differences were detected between human and horse PBL in response to adenosine and erythro-9-(2hyroxy-3-nonyl) adenine (EHNA), a competitive inhibitor of' adenosine deaminase. In the first assay, mitogen-stimulated PBL from horses were more sensitive to adenosine. In the second assay, adenosine was added to PBL cultures at various times after PHA addition. Adenosine inhibited mitogenesis in horse PBL if added within the first 24 h. In human PBL cultures, adenosine inhibited mitogenesis only if added within the first 4 h. The third assay measured capacity of PHA-stimulated human and horse lymphocytes to escape inhibition by adenosine or EHNA. At the end of a 72-h culture period, horse PBL were still inhibited by adenosine and EHNA, but human PBL were not. EHNA and adenosine together caused synergistic inhibition of mitogenesis in both human and horse PBL. With prolonged incubation (72 h), synergistic inhibition was detected only in horse PBL. With high-pressure liquid chromatography, nucleotide levels in erythrocytes of normal, carrier, and CID