Figure 3. Recombinant IgG2a Fc multimers (M045) downregulate B cell activation markers in EAMG.
Splenocytes were isolated and stained with APC-labeled anti-mouse CD19, FITC-labeled anti-mouse BAFF-R, eFluor 450-labeled anti-mouse CD16/CD32 (for FCγRIIB) and PE-labeled CD40. Representative plots and bar diagrams showing the percentage of CD19+ B cells (a), CD19+CD40+ B cells (b), CD19+BAFF-R+ B cells (c) and the intensity of cell surface inhibitory FcγRIIb protein expression (d) are shown. Inhibitory FcγRIIb mRNA expression was determined by Multiplex PCR. Total RNA, extracted from B cells, was reverse transcribed and a 172bp fragment corresponding to FcγRIIb was amplified and separated on a 2% agarose gel. Gels were densitometrically scanned and cDNAs were normalized to that of &beta:-actin, which was co-amplified along with the cDNA of interest. (e) Representative gel and bar diagram showing relative FcγRIIb mRNA expression in B cells from recombinant IgG2a Fc multimers (M045) and IVIG treated compared to PBS treated controls. The values in the bar diagram represents the mean ± SEM of triplicate values of three separate experiments. Significance at p<0.05. *, compared to PBS; ♠, compared to IVIG.