DECREASED BIOACTIVITY OF CIRCULATING PROLACTIN IN PATIENTS WITH RHEUMATOID ARTHRITIS

Growth hormone and prolactin (PRL) were measured by radio-immunoassayin sera of 36 patients with rheumatoid arthritis (24 femalesand 12 males) and of 50 normal blood donors (25 males and 25females). The bioactivity of PRL was also determined for bothgroups, using the Nb2 rat lymphoma proliferation assay. Althoughno significant difference was found between serum PRL valuesof patients and controls when determined by radio-immunoassay,the bioactivity of PRL was significantly decreased in patientssera, when compared to values obtained in age and sex-matchedcontrols. This decreased PRL bioactivity could not be attributedto drug treatments administered to the patients examined. KEY WORDS: Rheumatoid arthritis, Prolactin bioactivity, Prolactin immunoreactivity ^* Present address: Shaughnessy Hospital, 4500 Oak St., Vancouver,B.C., Canada. Present address: MRC Reproductive Biology Unit, 37 ChalmersSt., Edinburgh EH3 9EW, UK.     

Production and Characterization of Human-Human and Human-Mouse Hybridomas Secreting Rh(D)-Specific Monoclonal Antibodies

Human monoclonal antibodies specific for the Rh(D) antigen were produced by cell lines generated by the fusion of pooled Epstein-Barr virus (EBV)-transformed B-cell lines secreting Rh(D) antibodies with the murine myeloma cell line NS.1 or with the human lymphoblastoid cell line HOA.1. The selection of hybrids was achieved in RPMI 1640 medium containing HAT and ouabain. Higher fusion efficiency was obtained with the NS.1 cell line; however, the hybrids with HOA.1 exhibited a greater clonal stability. The products of four clones (three human-human and one human-mouse) that consistently secreted antibodies for over 11 months were tested for specificity with a panel of red cells of various Rh phenotypes. The supernatants of all four clones showed anti-Rh(D) specificity but failed to react with the red cell Du phenotypes categorized as DV(Dw+) and DVI. Two of the three human-human clones secreted IgM(lambda) and the third IgG(kappa). The human-mouse clone produced IgG(kappa) antibody.     

Pituitary Hormones and Contact Sensitivity in Rats

Hypophysectomized (Hypo-X) rats do not develop contact sensitivity to dinitrochlorobenzene (DNCB). Daily treatment with prolactin or growth hormone completely restores the DNCB-reactivity of Hypo-X animals. Treatment of such animals with ACTH, FSH, LH, TSH or HCG has no restoring potential. Treatment with ACTH in addition to prolactin or growth hormone antagonizes restoration of Hypo-X rats. These experiments indicate that the pituitary gland has the potential of regulating contact sensitivity.