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Biomedical subjects

S T Roodman

Publications and source records attributed to S T Roodman.

At least 37 records · Page 2Linked to original sources
PubMed1988

Decreased T helper cell function in patients with cystic fibrosis.

T cell immune function was further evaluated in cystic fibrosis (CF) patients. CF patients, regardless of severity of pulmonary disease or colonization with Pseudomonas aeruginosa, had lower percentages of T helper cells (p less than 0.01) and decreased T helper function as demonstrated by diminished T help for control B cell pokeweed mitogen-stimulated IgG (p less than 0.01) and IgM (p less than 0.01) synthesis. Increased T suppressor function, measured by co-culture with control B and T cells, was noted in only 25% of CF patients. CF patients' T cells exhibited decreased allogeneic T cell cytotoxicity compared to normal controls (p less than 0.01). This study extends previous studies demonstrating decreased T cell functions in CF patients and indicates a specific decrease in T helper function.

Adolescent↗
PubMed1986

Time relationship of immune changes to HTLV-III/LAV seroconversion in patients with hemophilia.

Longitudinal immune studies of patients with hemophilia A were begun in 1982 by the Regional Hemophilia Center in St. Louis, Missouri. Serum samples collected from 74 participants between 1982 and 1985 were analyzed for antibody to human T-lymphotropic virus type III (HTLV-III)/lymphadenopathy-associated virus (LAV). The incidence of antibody to HTLV-III/LAV has increased significantly in this population of patients with hemophilia. Only one of eight hemophiliacs had detectable antibody before July 1982, whereas 88.7% (55/62) were positive in 1985. T-cell surface markers were markedly abnormal in seropositive hemophilia patients with decreased percentage and number of OKT4-positive cells compared with seronegative hemophiliacs and controls. Lymphoproliferative responses to mitogens and antigens were normal in seronegative hemophilia patients. Seropositive hemophiliacs, compared with seronegative hemophiliacs, had significantly decreased lymphoproliferative responses, especially to pokeweed mitogen, tetanus, and Candida stimulations. Immune studies of seven HTLV-III/LAV seropositive hemophiliacs revealed antigen unresponsiveness and decreased T4 cells 2 to 32 months prior to development of full-blown AIDS. Longitudinal immune studies from 1983-85 revealed increasing number of seropositive hemophiliacs with antigen unresponsiveness and decreased T4 cells.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Heart graft arteriosclerosis. An ominous finding on endomyocardial biopsy.

Heart graft arteriosclerosis remains a severe and irreversible complication of allogeneic heart transplantation despite prophylactic therapy. Immunologically mediated endothelial damage has been proposed as a stimulus for the development of graft arteriosclerosis. The vascular lesions may accumulate large amounts of lipid resembling atheromas, or may be purely proliferative, as illustrated in the case of a 42-year-old heart transplant patient who developed slowly progressive graft dysfunction at eight months posttransplantation. Endomyocardial biopsy ten months posttransplantation revealed proliferative arteriolar occlusion, while changes on the coronary angiogram were minimal. Repeat biopsy at eleven months showed ischemic myocardial necrosis. The patient expired shortly thereafter. On postmortem examination, proliferative graft arteriosclerosis affecting both intramural and epicardial vessels was present, along with massive biventricular infarction. Tissue immunofluorescence studies demonstrated extensive vascular deposition of immunoglobulin and complement. We propose that (1) the presence of proliferative arteriolar occlusion on endomyocardial biopsy is predictive of poor heart graft survival; (2) proliferative graft arteriosclerosis may appear as advanced small vessel disease before extensive large vessel involvement is detected by coronary angiogram; and (3) immunofluorescence results support an immune-mediated mechanism of vascular injury in proliferative heart graft arteriosclerosis.

Adult↗
PubMed1982

Characterization of RNP and Sm ribonucleoprotein nuclear antigens.

Antibodies to the RNase-sensitive RNP and to the RNase-resistant Sm nuclear antigens were used to affinity purify these antigens from a saline extract of rabbit thymus acetone powder. Determination of the protein subunits recovered by either glycine-HCl, pH 2.8, or 2.5 M MgCl2 elution on gradient sodium dodecyl sulfate-polyacrylamide electrophoresis containing mercaptoethanol revealed that RNP was composed of five proteins with mol. wts from 10,000 to 15,000 whereas Sm contained the same or similar five chains plus six additional subunits with mol. wts from 21,000 to 42,000. RNase treatment of the thymus extract increased the recovery in Sm of the same bands compared to untreated extract. Thus, RNP and Sm appear to have different numbers of protein components and RNP may be a subset of Sm. Sucrose gradient centrifugation of the 125I-labeled, pH 2.8 eluted antigens gave peaks of 3 and 6S for RNP and Sm, respectively. Sucrose gradient centrifugation of the crude untreated thymus extract followed by quantitative single radial immunodiffusion analysis of each fraction produced a broad peak from 16S to the top of the gradient while pretreatment of the extract with RNase resulted in a discrete 6S peak. These results indicate that in rabbit thymus acetone powder native RNP and Sm exist as larger polydisperse complexes with additional material including RNA and that after acid elution or RNase treatment the antigens are found in a smaller monodisperse form.

Antigens↗
PubMed1981

Temperature-sensitive binding of solid phase C1q to aggregated human immunoglobulin G.

The first component of complement (C1q) coupled to Sepharose by cyanogen bromide was found not to bind aggregated human gamma-globulin or immune complexes at room temperature, whereas at 4 degrees C binding was nearly complete. The temperature sensitivity of solid phase C1q binding was reversible. Elution of aggregated human gamma-globulin bound at 42 degrees C was possible by raising the temperature to 23 degrees C. However, free C1q or C1q adsorbed onto polystyrene balls could bind immune complex-like material at both 23 and 4 degrees C. The conformational restraints of C1q covalently coupled to a solid support may not allow functional activity at elevated temperatures.

Chromatography, Affinity↗
PubMed1981

Acute non-A, non-B hepatitis with serum sickness-like syndrome and aplastic anemia.

We treated a patient in whom acute non-A, non-B hepatitis was complicated by a serum sickness-like syndrome (rash, arthralgias). Serum from this patient demonstrated a fall in C3, C4, and total hemolytic complement levels during the syndrome, in association with circulating IgM immune complexes. Fatal aplastic anemia developed later in the patient. This case illustrates that non-A, non-B hepatitis may be complicated by immune complex features that have previously been emphasized to occur with acute hepatitis B. Additional evidence supporting the occurrence of this clinical picture in non-B forms off viral hepatitis is presented.

Acute Disease↗
PubMed1981

Detection of immune complexes using a solid-phase C1q polystyrene ball assay.

A polystyrene ball C1q solid-phase assay (PSB C1q SPA) has been developed for quantitating immune complexes in human serum. While similar to the previously reported solid-phase C1q assays in principle, the use of polystyrene balls with a specular finish has resulted in an assay with significantly improved accuracy, sensitivity and reproducibility. The sensitivity of the assay based on the amount of AHGG bound per microgram C1q added was approximately 12-fold higher in the PSB assay compared to the polystyrene tube solid-phase C1q method. In order to correct for variable background contributions in different samples, values obtained with heat-inactivated C1q were subtracted from each experimental result. Reproducibility studies yielded a coefficient of variation (CV) of 10 and 4% in day-to-day assays using 25 microgram and 100 microgram AHGG/ml normal serum, respectively compared to 11--15% for the tube technique. Within run measurements gave a CV of 37 and 20% at the low and high levels of AHGG. Aggregated human gamma-globulin (AHGG) was used as a model immune complex and when chromatographed on Biogel A-15m yielded major fractions at greater than or equal to 15,000,000 and 150,000 daltons. Maximum binding of AHGG to PSB C1q occurred with aggregates greater than 15,000,000 daltons. Optimum binding of human albumin-anti-albumin complexes in the PSB C1q SPA occurred at a molar ratio of 1 : 1.5. The size distribution of this complex active in the assay determined by sucrose density gradients was 14--32 S with peaks at 21 and 27 S. A normal range of immune complexes was determined as 15 +/- 8 microgram AHGG equivalents (+/- 2 S.D., n = 65). Approximately 70% of rheumatoid arthritis, linear scleroderma, vasculitis, Sjögren's and glomerulonephritis and 40% of SLE patients were above 2 S.D. of normal. SLE patients demonstrated elevations in immune complexes only during periods of increased disease severity. The assay was a useful monitor of plasmapheresis in an SLE patient, showing decreases in immune complexes after each plasmapheresis. DNA did not interfere with AHGG binding whereas lipemia prevented detection of added AHGG.

Antigen-Antibody Complex↗
PubMed1980

Isolation and purification of human C1q from plasma.

C1q was purified to homogeneity from human plasma by a 3-step purification procedure. Plasma was euglobulin precipitated, and the redissolved precipitate chromatographed on a rabbit IgG-Sepharose column. The 1 M NaCl buffer eluate was passed directly through a rabbit anti-human IgG-Sepharose affinity column. C1q freed of IgG was present in the flow through. The rationale for this scheme to remove IgG free and that bound to C1q is discussed. Overall recovery of C1q was about 40% with IgG less than 4 microgram/mg C1q. In SDS-polyacrylamide electrophoresis with non-reducing conditions bands at 52,000 and 42,000 daltons were demonstrated while with reducing conditions bands at 26,000, 24,000 and 20,000 daltons were found as reported by others. C1q was found to be stable at 4 degrees C for 1 year in a 1 M NaCl, 0.4 M Tris, 10% sucrose, 0.005 M EDTA, 0.02% NaN3, pH 8.6 buffer.

Centrifugation↗