CD34 and rheumatoid arthritis: Methotrexate treated RA patients had a median of 4.4 CD45+ CD34+CD11b+ cells/μL and 3366 mature fibrocytes/105 monocytes (n = 11) versus untreated with 6.2 CD45+ CD34+CD11b+ cells/μL and 6368 mature fibrocytes/105 monocytes (p = 0.16 and p = 0.05 respectively).