Serology and immunoglobulin profile in rheumatoid arthritis.

One hundred and twenty cases of clinically diagnosed rheumatoid arthritis, 80 non-rheumatoid cases suffering from various other diseases and 40 healthy individuals were investigated for the presence of rheumatoid factor, quantitation of serum immunoglobulin, demonstration of ANA and LE cell phenomenon. Microlatex agglutination test of serum for rheumatoid factor showed 56.6% positivity in rheumatoid group and 3.7% positivity in non-rheumatoid group. All three serum immunoglobulins (IgG, IgM, IgA) were raised in serum in significant titre in cases of rheumatoid arthritis, whereas only IgA lever was elevated in the group of non-rheumatoid diseases. ANA and LE cell phenomenon were observed in 11.7% and 4.4% cases of rheumatoid arthritis who had severe underlying disease. In non-rheumatoid group, only one of 6 cases of systemic lupus erythematosus showed rheumatoid factor and that too in an insignificant titre (less than 1:20). Synovium and synovial fluid contained plenty of plasma cells and lymphocytes. It has been observed that RF appears first in synovial fluid and it may take several months to a year to attain detectable level in serum.

Culture of nocardioform bacilli from leprosy patients & clinical evaluation of nocardioform bacilli derived antigen.

An antigen derived from cultured nocardioform bacilli was compared with Mitsuda lepromin in intradermal skin test reactions. Nocardioform bacilli were cultured in gelatin minimal medium from the tissue fluid of 85 lepromatous patients (56 M, 29 F). Of these, 65 samples showed uncontaminated growth of the organism, which were pooled for the manufacture of the test antigen. This antigen was intradermally tested in 50 untreated leprosy patients irrespective of the type, together with Mitsuda lepromin and sterile gelatin minimal media, which served as a control. No early reaction was observed at 72 h, while the late reaction at 28 days was positive in all patients in the Tuberculoid (TT) group with both antigens. Eighteen patients (81.8%) in the Borderline tuberculoid (BT) group reacted strongly to Mitsuda lepromin at 28 days, while 21 patients (95.5%) in this group showed a strong late reaction with the test antigen. The lepromatous (LL) group did not show any reaction with the two antigens. It is inferred that nocardioform bacilli are easy to cultivate, and that the test antigen compares well with Mitsuda lepromin.

Homologous radioimmunoassay and radioreceptorassay of gonadotropic hormone for an Indian carp Catla catla.

A homologous radioimmunoassay (RIA) for Indian carp (C. catla) gonadotropin (GtH) was developed by using purified Catla GtH and its specific antiserum. In Ouchterlony agar diffusion, antisera raised against purified Catla GtH (cGtH), showed clear crossreaction. Catla-anti GtH (anti-cGtH) did not cross-reacted with Catla TSH enriched fraction. Immunocrossreaction was further confirmed with competitive binding inhibition studies where displacement of radiolabelled cGtH was precisely linear against increasing concentrations of cGtH, hence this was later used as standard curve for RIA. Competitive binding inhibition was also observed with purified murrel GtH, silver carp GtH and Cyprinus GtH, using varied doses. Both murrel and silver carp GtH showed clear parallelism with cGtH, while Cyprinus GtH inhibition slope was less steeper. Mammalian GtHs (hCG, oLH, oFSH), bTSH and bPRL had no crossreaction with anti-cGtH. Radioreceptorassay (RRA) for cGtH was developed by preparing plasma membranes from Catla oocytes. Binding of 125I-cGtH to oocyte plasma membranes showed saturability with high affinity (Ka = 0.11 X 10(13)M-1) and low capacity (17 fmol/mg protein). Displacement of 125I-cGtH in receptorassay by cold cGtH was linear and therefore served as standard curve. The interassay and intrassay variability in RIA was 7.9% and 3% while that of RRA was 5% and 3% respectively. Sensitivity of RIA was in the picogram level whereas it was in nanogram level by RRA. Determination of carp pituitary and serum GtH content by RIA and RRA showed the consistency, precision and validity of these assays. Although RRA was comparatively less sensitive than RIA, it was convenient, quick and less expensive.