Interference of antigen selection in memory B cells from SS patients.

<p>(<b>A</b>) Replacement:silent ratio (R/S ratios) were calculated for the complementary determining regions CDRs (black) and framework regions (white) for the heavy chain of both memory unswitched and switched B cells. A significant higher R/S ratio in the CDRs was observed in memory switched vs memory unswitched B cells. (<b>B</b>) The graphs show the ratio of replacement mutations in CDR1 and CDR2 (R_CDR) to the total number of mutations in V region (M_V) plotted against M_V for the memory unswitched and switched B cells from SS patients. The dark and the light grey area indicate the 90% and 95% confidence limits for the probability of random mutations, respectively. A data point outside these areas represents a sequence that was antigen selected. The data were obtained using the Immunoglobulin Analysis Tool software <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114575#pone.0114575-Rogosch1" target="_blank">[22]</a>.