a study has been made of the presence of the major rheumatoid factor cross-reacting idiotype ( rcri ) in the serum of patients with seropositive and seronegative rheumatoid arthritis as well as in the cytoplasm of plasmacells induced by cultivation of peripheral blood leucocytes ( pbl ) from the same ra patients and from normal humans .
C0229664
peripheral blood
C0023516
leucocytes