Comparative CD43 behavior on monocytes and lymphocytes in kidney transplants

In human cultured monocytic cells stimulated by cytokines, CD43 was demonst rated to exhibit a modification of sialylated epitopes (dys-sialylation) [S oler et al: Leukoc Bio[ 1997;61:609-618]. Therefore, we chose to investigat e CD43 behavior on patients who present pathological status implicating mon ocytes after renal graft (KTR). We performed flow cytometry after immune st aining using monoclonal antibodies to CD43 sialic acid-dependent (L60) and -independent (L10) epitopes, Compared to normal controls, mean fluorescence intensity was never altered on lymphocytes. Conversely, on monocytes, we f ound different profiles with L60: 26% of patients having normal CD43 expres sion, 54% displayed decreased values and 20% had a double population of mon ocytes, the major one being normal and the minor one with a very low staini ng, Decreased values were more frequent among KTR during the first 3 months following transplantation. L10 immunostaining was not altered on monocytes in patients with low values of CD43 staining by L60, confirming that the m echanism involved was a CD43 dys-sialylation. We investigated a possible ro le of cyclosporin (CsA) on human monocytic (THP-1) and lymphoid (Jurkat) ce ll lines. CsA decreases CD43 expression in monocytic and not in lymphoid ce ll lines and could be responsible for the specific dys-sialylation of KTR m onocytes. Whatever, CD43 dys-sialylation might lead to functional abnormali ties of monocytes in KTR, possibly involving the adhesion process. Copyrigh t (C) 2000 S. Karger AG, Basel.