Figure 2

IgA and IgG expressing plasma cells in salivary glands of pSS patients and non-SS controls. A) IgA and B) IgG positive plasma cells detected in salivary glands of a pSS patient with FS = 1, a pSS patient with FS = 4, in a subject with chronically inflamed glands (CIG) and a subject with normal gland (NG) histology. Inserts represent higher magnifications of IgA or IgG plasma cells for each group. IgA expressing plasma cells were detected interstitially as small cell clusters close to ductal and acinar epithelium in all groups tested and in the periphery of infiltrates in pSS with FS = 1 and FS ≥2 (A). IgG expressing plasma cells were found both inside and in the periphery of large focal infiltrates in pSS patients with FS = 1 and FS ≥2, whereas interstitial accumulation of IgG expressing plasma cells was observed mostly in the pSS patients with high FS (B). C) Amount of IgA or E) IgG positive interstitial plasma cells presented as number of cells/mm² and D) IgA or F) IgG positive cells in the focal infiltrates presented as number of positive cells per mm². Grey bars represent FS = 1 (n = 8), black bars represent FS ≥2 (n = 7), striped bars represent chronic inflammation (n = 5) and white bars represent normal gland histology (n = 5). Results presented as mean ± SEM. Statistical analyses determined by Kolmogorov-Smirnov and Student t test (*P < 0.05).