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C L Christian

Publications and source records attributed to C L Christian.

At least 55 records · Page 3Linked to original sources

Clues from genetic and epidemiologic studies.

There are clear indications that genetic variables influence the pathogenesis of SLE. The frequency of the disease in first-degree relatives of SLE subjects appears to be in the range of 1-2%, but this is in great excess relative to the frequency of SLE in the general population. The frequency of concordance of the disease in monozygotic twin pairs is in excess of 50%. The frequency of concordance of dizygotic twins may be no higher than that in other first-degree relatives. Data in twins support the conclusion that familial aggregation is due to genetic rather than to other familial factors. The high female-to-male ratio of patients with SLE may reflect sex hormonal influence on immunoreactivity rather than the genetic aspects of sex per se. The approximately threefold higher incidence of SLE in black subjects relative to white, in some studies, may reflect a heightened activity of the humoral immune system in blacks.

Antibodies, Antinuclear↗

Vasculitis with hepatitis B antigenemia: long-term observation in nine patients.

The development of generalized necrotizing vasculitis in association with hepatitis B antigenemia is the first example in man of a chronic rheumatic disease presumably caused by a viral infection. This report reviews the experience in nine biopsy-proven cases of hepatitis B-associated necrotizing vasculitis followed for up to six years. The natural history of the disease is emphasized and the manifestations of patients with vasculitis who carry hepatitis B antigen are compared with those of vasculitis patients who are antigen negative.

Adult↗

Studies of twins with systemic lupus erythematosus. A review of the literature and presentation of 12 additional sets.

To assess the role of genetic factors in systemic lupus erythematosus (SLE), 12 twon pairs (seven definitely monozygotic, three definitely dizygotic) of which one or both twins had SLE, were studied and compared to 17 twin pairs (12 definitely monozygotic) previously described. In the present series, four of seven (57 per cent) definitely monozygotic pairs were clinically concordant for SLE, satisfying the preliminary criteria of the American Rheumatism Association (ARA). Concordance for the presence of antinuclear factor (ANF) and hypergammaglobulinemia was 71 and tinuclear factor (ANF) and hypergammaglobulinemia was 71 and 87 per cent, respiectively. These data closely agree with those on the 12 definitely monozygotic sets previously described. All three of the dizygotic sets in the present series were discordant for clinical SLE, although one clinically well twin had marked serologic abnormalities. Comparison of these data with thos from other first degree relatives of out twins clearly suggests a strong genetic component in the pathogenesis of SLE. The relative contribution of nongenetic and environmental factors to the expression of the disease is discussed.

Adolescent↗

Hereditary C2 deficiency in systemic lupus erythematosus and acquired complement abnormalities in an unusual SLE-related syndrome.

Early study of kindreds with C2 deficiency indicated that absence of C2 had no detrimental effect on affected individuals. Studies of additional kindreds, however, show a high incidence of SLE and other connective tissue diseases among homozygous C2-deficient members. A group of patients with an unusual SLE-related syndrome is described. In common with certain SLE patients they have marked depression of early complement components and presence of circulating Clq precipitins. It is suggested that early complement components are involved in specific host defense mechanisms and deficiencies of these components may predispose to such diseases.

Antibodies, Antinuclear↗

Naturally occurring low molecular weight IgM in patients with rheumatoid arthritis, systemic lupus erythematosus and macroglobulinemia. I. Purification and immunologic studies.

A method for purification of low molecular weight IgM (LMW IgM) which utilized salt precipitation, gel filtration, and insoluble immunoadsorbents is described. The yield from pathologic sera containing LMW IgM in the range of 15 to 36 mg% was approximately 20%. Antisera prepared against LMW IgM, IgM, and reduced-alkylated IgM recognized common determinants. Purified LMW IgM from seropositive rheumatoid subjects did not have rheumatoid factor activity in agglutination tests but demonstrated binding to 125I-labeled aggregated IgG. LMW IgM from a patient with SLE and vasculitis had anti-nuclear factor activity and anti-native DNA activity. When complexed with reduced-alkylated aggregated IgG, LMW IgM and IgM with anti-IgG activity were essentially equivalent on a weight basis in complement fixation. The source and function of LMW in biologic processes remain unknown.

Animals↗

Naturally-ocurring low molecular weight IgM in patients with rheumatoid arthritis, systemic lupus erythematosus, and macroglobulinemia. II. Structural studies and comparison of some physicochemical properties of reduced and alkylated IgM, and low molecular weight IgM.

Some physicochemical properties of naturally occurring low molecular weight IgM (LMW IgM), IgM and their subunits obtained by reduction-alkylation were compared. On the basis of analytical ultracentrifugation, SDS polyacrylamide electrophoresis, analytical Sephadex chromatography, and heavy (H) and light (L) chain composition purified LMW IgM had an S20,W constant of approximately 8S, a molecular weight of 195,000 to 205,000 and a structural formula H2L2. Reduction and alkylation of IgM (IgM RA) by two techniques produces two components which could be distinguished by analytical ultracentrifugation, sucrose density ultracentrifugation, and gel filtration studies. IgM RA-cys had an estimated molecular weight similar to LMW IgM and IgM-2ME had physical properties similar to IgG. The molecular weights of H and L chains of IgM and LMW IgM were similar: 69,000 to 75,500 and 26,000 to 27,000, respectively. Unlike LMW IgM and IgM RA-cys, the less dense IgM RA reduced with 2ME dissociated into half subunits, and free H and L chains in SDS gel electrophoresis, indicating that it lacked intra-subunit disulfide bonds. J chain was not detected in LMW IgM or in the chromatographically purified reduced-alkylated subunits from a patient whose IgM contained J chain. Carbohydrate analyses of IgM, LMW IgM, and reduced-alkylated IgM products did not demonstrate differences in individual sugars or in the percentage of total carbohydrate. The different sedimentation and gel filtration properties of the two components obtained by reduction-alkylation of IgM could not be attributed to variations in peptide chain or carbohydrate content, rather they are probably dependent on conformational changes resulting from variable, reduction of intra-subunits disulfide bonds.

Antigen-Antibody Reactions↗