CD4 and autoimmune disease: Because higher serum IgG levels are likely a consequence of the autoimmune disease process that generates autoantibodies [34], we compared pSS anti-Ro+ and pSS anti-Ro− patients directly and found that anti-Ro+ subjects had a significantly higher proportion of SG CD3+CD4+CD45RA− T cells than anti-Ro− pSS subjects (anti-Ro+: 38.3 ± 2.5 vs. anti-Ro−: 26.9 ± 2.7; p = 0.0027).