Open AccessEvaluation of chemiluminescence, procoagulant activity and antigen presentation by monocytes from lepromatous leprosy patients with or without reactional episodes
Author(s) -
Dilvani Oliveira Santos,
Philip Noël Suffys,
Ana Livia Gomes Moreira,
Kristel Aryanna Mendiola Bonifacio,
Jorge Salgado,
Danuza Esquenazi,
Álvaro Luiz Bertho,
Euzenir Nunes Sarno
Publication year - 1994
Publication title -
leprosy review
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 43
eISSN - 2162-8807
pISSN - 0305-7518
DOI - 10.5935/0305-7518.19940008
Subject(s) - lepromatous leprosy , muramyl dipeptide , peripheral blood mononuclear cell , monocyte , mycobacterium leprae , immunology , concanavalin a , medicine , antigen , histiocyte , leprosy , biology , immune system , in vitro , biochemistry
In this study, we evaluated the activity of peripheral blood mononuclear cells (PBMC), isolated from treated and untreated lepromatous leprosy patients, from lepromatous leprosy patients during and after reactional episodes (erythema nodosum leprosum (ENL) and reversal reaction (RR)), and from normal healthy individuals. We determined reactive oxygen intermediate (ROI) production, procoagulant activity (PCA) and HLA-DR antigen expression of monocytes, besides lymphoproliferation, both in the presence and absence of various stimulatory agents. Phorbol myristate acetate (PMA) stimulated ROI production by monocytes from all the groups studied, with patients during reactional episodes (ENL and RR) showing a significantly higher response (p < 0.009 and p < 0.00001). Irradiated Mycobacterium leprae, although having little effect when added alone, strongly suppressed PMA-stimulated ROI production. Muramyl dipeptide (MDP) had no influence on either basal or on PMA-induced ROI production. Basal monocyte PCA, as well as M. leprae or concanavalin A (ConA)-induced monocyte PCA was comparable in monocytes from all the groups studied. ConA was able to induce mitogenic activity in mononuclear cells isolated from all the groups studied. M. leprae, although stimulatory for normal individuals, did not induce lymphoproliferation in lepromatous leprosy patients, except for cells from patients during RR, which responded equally to M. leprae and to ConA. The absence of M. leprae-induced lymphoproliferation in lepromatous leprosy patients is not caused by the lack of basal HLA-DR expression, as PBMC from all individuals studied showed the same level of this antigen. Our results suggest an increase of spontaneous or PMA-induced monocyte activity, as detected by ROI production, during the reactional episode; addition of M. leprae suppressed this response. The increase in monocyte activity could be correlated with the increase of lymphoproliferation response to M. leprae during RR, but not during ENL. The importance of a possible immune suppressive action of M. leprae is discussed.