The effect of B lymphocytes on immune response of periodontal bacteria and osteoclast differentiated reactor-RANKL expression
Lin, X.-p.; Han, X.-z.; Wei, W.; Martin A, T.
Shanghai Kou Qiang Yi Xue 18(4): 392-396
2009
ISSN/ISBN: 1006-7248 PMID: 19760013 Document Number: 637681
To study whether B lymphocytes involve in bone resorption in periodontal disease by evaluating RANKL expression of B lymphocytes in immune response to aggregatibacter actinomycetemcomitans (Aa). The expression of mRNA transcripts involved in day 1 and day 7 responses of cytokines in cultured rat splenocytes was determined by RT-PCR; The percentage of RANKL-expressing IgG positive cells by B cells in cultured rat splenocytes was measured by flow cytometry; and B lymphocytes capacity for induction of osteoclast differentiation was evaluated by TRAP staining. SPSS 10.0 software package was used for statistical analysis. The expression of IL-4 and IL-10 in cultured cells was not changed in the presence of Aa on day 1, after culture for 7 days; The percentage of B lymphocytes, all RANKL mRNA transcripts and percentage of RANKL-expressing IgG positive cells were significantly increased in the presence, compared to the absence of Aa. These increases were considerably greater in cells isolated from immunized than non-immunized rats. B cells from Aa immunized rats significantly increased induction of osteoclast differentiation (P<0.01), and addition of human OPG-Fc into the culture significantly inhibited its induction (P<0.05), and was RANKL-independent. B lymphocytes contribute to bone resorption in periodontal disease through involving in the immune response to Aa, up-regulation of RANKL expression and increasing induction of osteoclast differentiation.