Virologic studies on rheumatoid arthritis

Complete protein sequences of the variable regions of the cloned heavy and light chains of a human anti-cytomegalovirus antibody reveal a striking similarity to human monoclonal rheumatoid factors of the Wa idiotypic family

The complete amino acid and nucleotide sequences of the variable regions of the heavy and light polypeptide chains of a human neutralizing IgGl anti-cytomegalovirus (CMV) antibody reveal a striking homology to IgM rheumatoid factors (RFs) of the Wa idiotypic family. The anti-CMV antibody and Wa RFs have in common VKIIIb, JKl, and VHIa gene segments but use different DH and JH gene segments. The anti-CMV antibody does not have RF activity and does not express the Wa idiotype. The Wa RFs do not have anti-CMV activity. A subset of Wa RFs, however, and the anti-CMV antibody do share several idiotypes on the VHIa and VKIIIb polypeptides. Since there are major differences in the antigen binding characteristics and some of the other expressed idiotypes, these data suggest that the D and J region amino acids are crucial to such specificities. Although the use of such highly homologous gene segments in different immune responses is well-documented in murine systems, these data represent the first such example in the human.

Persistent rubella virus infection associated with chronic arthritis in children

We isolated rubella virus from lymphoreticular cells in 7 of 19 children with chronic rheumatic disease, including patients with systemic-onset juvenile rheumatoid arthritis (Still's disease) (1 of 5), polyarticular juvenile rheumatoid arthritis (2 of 2), pauciarticular juvenile rheumatoid arthritis (2 of 6), and seronegative spondyloarthritis (2 of 6). In contrast, rubella virus was not isolated from the control group, which included eight normal subjects and eight patients with other connective tissue diseases or traumatic joint effusion. In most members of the study group, mononuclear cells from both synovial fluid and peripheral blood were examined. Rubella virus was isolated from both cell populations in three patients, from only peripheral blood in one, and from only synovial fluid in two. In the children with systemic-onset juvenile rheumatoid arthritis, only peripheral blood was examined, and of the five samples analyzed, one was shown to have rubella virus. Virus was isolated on more than one occasion from four of seven persons. Persistence of rubella virus in lymphoreticular cells in 35 per cent of these cases of juvenile arthritis supports the view that the virus may be an etiologic agent in chronic human joint disease, but further work will be required to support this suggestion.

Interferon triggers experimental synovitis and may potentiate auto-immune disease in humans

From these data it appears that IFN is capable of stimulating prostaglandin E and hyaluronic acid production by human synovial fibroblasts in vitro and of initiating an inflammatory reaction in animal joints. In chronic arthritis its production may result from persisting viral or other antigenic stimulation. IFN may enhance the immune response and mediate the inflammatory process in the joint. Its role in the pathogenesis of rheumatic and various other autoimmune diseases is undergoing further study.

Chronic arthritis associated with the presence of intrasynovial rubella virus

In this report we present 21 instances in which live rubella virus was isolated from synovial fluid obtained from 6 cases of inflammatory oligoarthritis or polyarthritis over a period of 2 years in the absence of firm clinical evidence of rubella. In 3 cases (cases 1, 2, 6,) a persistent oligoarthritis predominantly affecting the knee joints occurred in 2 adult women and one man, lasting to date 27, 29, and 18 months respectively, and in one of these cases virions were found in cells of the synovial membrane. In case 3 a boy of 9 presented with an illness indistinguishable from the systemic variety of juvenile chronic arthritis (Still's disease). In case 4 a young man with persistent monoarthritis was found to have ankylosing spondylitis, and in case 5 a progressive erosive polyarthritis developed 5 years after an attack of rubella complicated by rubella arthritis. The virus was identified by a variety of virological techniques and infection confirmed by immunofluorescence and (in one case) electron microscopy.

Acute induction of joint inflammation in the rat by poly I . poly C

Intraarticular injection of interferon inducer, double-stranded polyinosinate-polycytidylate (Poly I . C) caused acute synovitis in rats. This acute inflammatory response was accompanied by an increased concentration of prostaglandin E (PGE) in the synovial tissue. Double-stranded polyadenylate-polyuridylate (Poly A . Poly U) was less potent than Poly I . Poly C in inducing synovitis and increasing PGE concentration, while single-stranded polyinosinate (Poly I) or polycytidylate (Poly C) were inactive in these respects. Intraarticular injection of partially purified mouse fibroblast interferon also induced synovial inflammation. The present results suggest that interferon may be a mediator of viral inflammatory responses.

Demonstration of anti-rubella antibody-secreting cells in rheumatoid arthritis patients

In the present study we describe a plaque-forming cell assay using erythrocytes coated with viral antigen, which detected anti-viral antibody-secreting cells against various viral antigens. These anti-viral antibody-secreting cell were studied in normal individuals with known viral infections and in rheumatoid arthritis patients. Rubella anti-viral antibody-secreting cells were present after induction in the peripheral blood of eight out of ten patients. No plaques were seen before induction. Synovial tissue of seven patients out of ten showed rubella-antigen-specific plaques before induction. In all three patients tested, the numbers of plaques increased after induction. The peripheral blood of only one patient showed plaque-forming cells against mumps virus and cytomegalovirus (CMV) antigen. No other patients showed any plaque against CMV, respiratory syncytial virus, mumps virus, measles virus, adenovirus, and varicella zoster virus antigens. The method appears to be promising in studying viral antibody-secreting cells in human immunopathology.

Hyporesponsiveness of lymphocytes to virus antigens in rheumatoid arthritis

The immune response of peripheral blood lymphocytes to measles, rubella, parainfluenza types 1, 2, and 3 RNA virus antigens and to varicella-zoster and herpes virus type 1 DNA virus antigens was evaluated in 14 patients with rheumatoid arthritis (RA) and 14 matched controls by assessing 3H-thymidine incorporation. The results demonstrated hyporesponsivenss of lymphocytes from RA patients to virus antigens and phytohemagglutinin (PHA), which did not appear to be nonspecific because of a lack of correlation between response to virus antigens and response to mitogens. The patterns of decreased responsiveness was suggestive of a relative restriction of hyporesponsiveness to RNA virus antigens.

Chronic arthropathy associated with rubella vaccination

Eleven children suffered recurrent ipisodes of knee stiffness ("catcher's crouch syndrome") after receiving HPV-77DK12 rubella vaccine. One was evaluated by arthroscopy and the synovium was found to be hypertrophied posteriorly and to protude in folds into the intercondylar notch and lateral joint space. Culture for rubella virus was unsuccessful. The author's observations provide evidence that "catcher's crouch syndrome" is a synovial disease and that chronic joint disease can be a sequela of rubella immunization.

Serum antibody in rheumatoid arthritis reactive with a cell-associated antigen. Demonstration by precipitation and immunofluorescence

A cell-free extract of human diploid B lymphocytes (Wil2) in continuous culture was used as the source of antigen in immunodiffusion to detect a precipitating antibody referred to as rheumatoid arthritis precipitin (RAP) in sera of patients with rheumatoid arthritis (RA). The prevalence of RAP was determined in various arthritides and other connective tissue diseases. It was found in 67% of patients with seropositive RA and in 62% of patients with Sjögren's syndrome associated with RA. But its frequency was lower in many other connective tissue diseases, including seronegative RA and Sjögren's syndrome without associated RA. Matching sera and synovial fluids from patients with seropositive RA were also studied. Differences in serum and synovial fluid RAP titers were demonstrated, but generally when RAP was present in serum, it was also present in synovial fluid and vice versa. Indirect immunofluorescence (IF) with Wil2 cells as substrate was used to demonstrate RAP and to determine morphologically the nature of the reactive cellular antigen. When cells were treated with commonly used fixatives, little or no staining with RAP positive sera was observed. This outcome was shown to be the result of the extreme solubility of the cellular antigen reactive with RAP. The antigen was retained best in a reactive form in Wil2 cells after fixation of cells with dry heat at 37 degrees C for 30 minutes, and it was demonstrated by IF staining as small round granules distributed in the nucleus and cytoplasm. IF was also employed to demonstrate that RAP is immunoglobulin belonging to IgG and IgM classes and not to IgA or IgD.

DNA polymerase activity of cultured rheumatoid synovial cells

Cultured synovial cells from 8 patients with rheumatoid arthritis (RA) and 7 subjects without joint disease were assayed and comapred for RNA-directed and DNA-directed DNA polymerase activity. No activity was found in either RA or control specimens using a synthetic RNA template that specificically detects oncornavirus RNA-directed DNA polymerase. The DNA-directed DNA polymerase activity of RA specimens was increased (P less than 0.10) in the high-speed pellet fraction of cell lysates. The possible relationship of these finding to virus infection in RA is disscussed.