INTERACTION BETWEEN DENDRITIC CELLS AND B CELLS DURING IMMUNE RESPONSE TO T CELL-INDEPENDENT ANTIGENS

Abstract

Abstract. Involvement of dendritic cells (DC) into switching of immune response to T-independent type 2 antigens (TI2 antigens) is poorly studied. The present study addressed some interactions between DCs and TI2-type antigens, i.e., with Streptococcus pneumoniae polysaccharide type 3 (S3), and polyvinylpyrrolidone (PVP, mw. of 360 kDa), as well as a role of antigen-loaded DCs for triggering the immune response. Shortterm treatment of DCs with TI-2 antigens induced their activation manifesting as an increase in numbers of CD80- and CD86-positive cells under the cell culture conditions. DCs loaded with TI-2 antigens were then mixed with normal murine splenocytes and cultured in complete RPMI 1640 medium for 4 days. The numbers of antibody- and immunoglobulin-forming cells (AFCs and IFCs, respectively) were determined by ELISPOT assay. Supplementation with TI2-treated DCs induced a 2.0 to 2.7-fold increase in specific immune response. Antigen-induced polyclonal response was enhanced by 40%. These data suggest a direct interaction between DCs and TI-2 antigens, and their presentation to murine splenocytes, thus leading to both specific and polyclonal B cell activation. B-1 cells are shown to play a main role in such response. Separation of loaded DC and splenocytes by semi-permeable membranes caused inhibition of this immune response.

Keywords

• дендритные клетки
• полисахарид s3 streptococcus pneumoniae
• поливинипирролидон
• т-независимые антигены типа 2
• индукция иммунного ответа in vitro