CD79A and rheumatoid arthritis: On the other hand, Newkirk et al. [71] identified differences in the types of E. coli pathogen colonization among subjects with rheumatoid arthritis, RF-positive patients were more commonly colonized with E. coli, phylogenetic group D, whereas RF-negative patients were more commonly colonized with E. coli, phylogenetic group B2, and these individuals also had lower joint scores and inflammatory markers yet higher IgA anti-E.