Effect of an hydro-alcoholic extract of Uncaria tomentosa (cat's claw) over dendritic cell subsets and HLA-DR/CD86 molecules by lipopolysacarides stimulus

Abstract

Objective. To determine the effect of an hydro-alcoholic extract of cat´s claw Uncaria tomentosa (uG) over lipopolysaccharides – treated dendritic cells (DC) and HLA-DR and CD86 molecules expression of peripheral blood samples obtained from healthy individuals. Materials and methods. Peripheral blood samples were collected from healthy individuals. Peripheral Blood Mononuclear Cells (PBMC) were isolated by centrifugation over density gradient, pre-treated with and without the addition of uG, and then stimulated for 24 h with lipopolysaccharides (LPS), then the cells were labelled with specific fluorescent monoclonal antibodies to HLA-DR, Linage type 1 (Lin1), CD11c and CD86 and prepared for flow. Results. Compared to PBMC with LPS but without uG group, we found a decrease of myeloid DC (mDC) percentage (p<0.05) and a tendency to increase plasmacytoid DC (pDC) percentage, both in a dose-dependent manner. There was a decrease in media fluorescence intensity (MfI) of HLA-DR in DCp between 500 and 1000 µg/mL of CC (p<0,001), but we found a increase in MfI of CD86 at all concentrations (p<0,05). There was no effect of uG over MfI of the HLA-DR or CD86 expression in mDC. Conclusions. uG showed a tendency to increase pDC percentage and decreased mDC percentage. uG did not affect the expression of CD86 and HLA-DR from mDC. This study demonstrates that uG promotes activation/differentiation of pDC, which has a demonstrated involvement in the adaptive immune response mechanisms.