Search PubMed⌕ Search

Biomedical subjects

R D Inman

Publications and source records attributed to R D Inman.

99 records · Page 6Linked to original sources
PubMed1980

The C1q binding assay in systemic lupus erythematosus: discordance with disease activity.

To investigate the relationship of C1q binding assay (C1qBA) to disease activity in systemic lupus erythematosus (SLE), a retrospective study was carried out on 232 C1qBA performed in 33 patients with SLE. When initial values were assessed (33 tests in 33 patients), there was no relationship between positive and negative C1qBA and abnormal renal function (P = 0.482, Fisher exact test). Of 87 tests performed during active renal disease, 34 (39%) were positive; of 48 tests during active non-renal disease, 25 (52%) were positive; of 83 tests when the disease was inactive, 45 (54%) were positive; and of 14 tests during episodes of infection, 10 (71%) were positive. Corresponding means for the C1qBA were follows: renal 65.66, non-renal 78.02, inactive 56.04, infection 135.79 (no significant differences by Student's t-test). There was no significant relationship with the C1qBA when comparing active disease (renal and non-renal) with inactive disease (chi 2 Yates = 1.875, P = 0.171). When renal function abnormalities were analyzed separately, the C1qBA values were independent of azotemia or proteinuria (chi 2 Yates = 1.399, P = 0.237). Patients were seen with progressive renal disease who had consistently negative C1qBA, as well as patients with benign clinical courses despite elevated C1qBA. The discordance of the C1qBA results with disease activity in SLE highlights the limitations of immune complex (IC) determinations by a single technique, and stresses the importance of evaluating such tests in terms of both their specificity and sensitivity. These data further suggest that the relationship of IC to the disease process in SLE may be a complex one.

Complement C1↗
PubMed1979

Binding of immunoglobulin G aggregates and immune complexes in human sera to Staphylococci containing protein A.

Using the Cowan I strain of Staphylococcus aureus, we compared the binding properties of human monomeric immunoglobulin (Ig)G and oligomeric or complexed IgG. Heat-aggregated IgG served as a model for complexed IgG and heat-killed, formalin-fixed S. aureus (StaphA) as a cellular receptor for IgG, in determining the parameters for oligomeric and monomeric binding. Because of its capacity for multipoint attachment, complexed IgG binding was favored over monomeric IgG binding, and this preferential binding was demonstrated kinetically in equivalent forward rates of binding but in a much slower rate of release from StaphA receptors. From binding studies, we determined which conditions maximize complexes IgG binding and minimized monomeric IgG binding and applied them to the development of an assay for aggregated IgG and immune complexes in human sera. The StaphA binding assay that was devised is quantitative, sensitive, and not complement dependent. It is relatively unaffected by factors such as heparin, complement fixation, native antibodies, and immunoglobulin concentrations, but is affected by the presence of rheumatoid factors. It compares favorably with two other complement-dependent assays of immune complexes, the 125I-Clq binding assay and the Raji cell assay, in terms of sensitivity and the size of immune complexes detected. Studies on the potential of the assay for detecting, isolating, and characterizing immune complexes in biological fluids are presented.

Antigen-Antibody Complex↗
PubMedDate not supplied

Immunologic sex differences and the female predominance in systemic lupus erythematosus.

The female predominance in many rheumatic disorders, most notably systemic lupus erythematosus, suggests that immunologic sex differences may modify susceptibility to disease. Clinical and experimental data indicate heightened humoral immunity and depressed cellular immunity in females compared with males. These differences appear to be mediated by sex hormones.

Adult↗
PubMedDate not supplied

Subluxation of the sacroiliac joints in a black female with ankylosing spondylitis.

A 55-year-old black female with ankylosing spondylitis (AS) is described. The patient had a severe flexion attitude secondary to a rotational subluxation at the sacroiliac joints with subsequent bony ankylosis. The sacroiliac abnormality has not been reported in AS patients. Sacroiliac joint laxity during multiple pregnancies might have contributed to the subluxation. The importance of this anatomic site in evaluating the surgical correction of the postural deformities of AS is stressed.

Female↗