Comparison of the effect of various stimuli on the leishmaniacidal capacity of human monocytes in vitro

J. Passwell, R. Shor, G. Keren, G. Messer, J. El-On

Research output: Contribution to journalArticlepeer-review

4 Scopus citations

Abstract

Leishmania organisms are obligate intracellular parasites of mammalian mononuclear phagocytes in vivo. In order to study the interactions of these parasites and mononuclear phagocytes, we have used a model of infection of Leishmania major in human monocytes in vitro. The presence of intracellular parasites did not alter the normal secretion of lysozyme or result in increased secretion of prostaglandin E2 (PGE2) or superoxide anion by the monocytes. Addition of concanavalin A (Con A), which binds to a specific membrane receptor, zymosan particles or endotoxin to infected monocyte monolayers, resulted in the expected increase in PGE2 secretion. In addition, the production of superoxide by infected monocytes treated with phorbol myristate acetate was not different from control uninfected cultures. Despite this evidence of biochemical activation, neither endotoxin, zymosan nor Con A had any parasiticidal effect on the intracellular parasites. In contrast, Con A-induced lymphokines from human mononuclear cells resulted in an increased killing of the intracellular amastigotes. These studies have shown that the induction of leishmaniacidal capacity of human monocytes is dependent on the type of stimulus used to induce activation.

Original languageEnglish
Pages (from-to)553-558
Number of pages6
JournalClinical and Experimental Immunology
Volume56
Issue number3
StatePublished - 26 Jul 1984

Fingerprint

Dive into the research topics of 'Comparison of the effect of various stimuli on the leishmaniacidal capacity of human monocytes in vitro'. Together they form a unique fingerprint.

Cite this