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Biomedical subjects

P Halberg

Publications and source records attributed to P Halberg.

At least 91 records · Page 5Linked to original sources

A new radioimmunoassay for IgM and IgG rheumatoid factors, based on a double antibody method.

A new radioimmunoassay has been developed for measuring IgM and IgG rheumatoid factors. Diluted sera from donors and patients were incubated with immunoprecipitates prepared from sheep serum and rabbit anti-sheep IgG antiserum. The precipitates were washed, and radioiodinated rabbit F(ab')2 fragments specific from human IgM or IgG were added. The precipitates were isolated from filtration and measured in a gamma counter. With this assay IgM rheumatoid factors were detected in sera from all patients with seropositive rheumatoid arthritis and in sera from 40% of patients with seronegative rheumatoid arthritis. IgG rheumatoid factors were found in sera from 68% of the seropositive and 40% of the seronegative patients. Gel filtration experiments demonstrated that it is possible to detect monomeric IgG rheumatoid factors and IgM rheumatoid factors of molecular weight smaller than pentameric IgM. Furthermore it has been shown that IgG rheumatoid factor activity is still present after reduction of IgM rheumatoid factors with dithiothreitol.

Animals↗

Deposits of immunoglobulin and complement in psoriatic lesions.

Biopsy specimens from 43 patients with psoriasis were studied by immunofluorescence microscopy. Deposits of complement C3 and/or immunoglobulins were seen in the vessel walls and/or in the dermal-epidermal junction of all of 21 patients with pustular psoriasis, acute guttate psoriasis, psoriatic arthropathy and erythroderma. similar deposits were seen in nine out of 22 patients with psoriasis vulgaris. Deposits were found in clinically uninvolved skin in only one of 37 patients. The results might suggest that the deposition of immune complexes in the vessel walls are of importance for the development of psoriatic lesions.

Complement C3↗

Enzyme-linked immunosorbent assay for determination of IgM rheumatoid factor.

A semi-automated enzyme-linked immunosorbent assay (ELISA) for determination of IgM rheumatoid factor was established. Human gammaglobulin (Cohn fraction II) was used as an antigen on a solid phase of polystyrene microtitre trays. The results were read on a spectrophotometer. ELISA and the sheep cell agglutination test were compared in a study of sera from 400 blood donors, 53 patients with active rheumatoid arthritis and of 200 sera received for routine determination of rheumatoid factor. The results of the two tests correlated well. The ELISA procedure was precise, objective, inexpensive and well suited for quantitative routine determination of IgM rheumatoid factor.

Adolescent↗

Deposits of immunoglobulins and complement in skin of patients with rheumatoid arthritis. Influence of anti-rheumatic treatment.

Immunopathological studies on skin biopsies from 88 patients with rheumatoid arthritis showed that one-third of them had deposits of IgM and/or C3 in the walls of small vessels immediately underneath the dermal-epidermal junction. The deposits in the vessel walls which may reflect subclinical immune complex vasculitis could be correlated to the occurrence of IgG-rheumatoid factor in the serum, but not to IgM-rheumatoid factor, other extra-articular manifestations, or to the occurrence of circulating immune complexes demonstrated by the complement consumption test or the thrombocyte aggregation test. Two untreated patients had granular deposits in the dermal-epidermal junction. Five out of 50 patients developed deposits in the dermal-epidermal junction during treatment with levamisole, penicillamine, or azathioprine, as observed by serial skin biopsies.

Anti-Inflammatory Agents↗

A clinical study of 32 patients with oral discoid lupus erythematosus.

Thirty-two patients (26 females, six males) with discoid lupus erythematosus of the oral mucosa have been studied. Patients with signs of dissemination were classified according to accepted criteria. Four patients had systemic lupus erythematosus as well as oral discoid lesions. Twenty-one patients had discoid skin lesions. Eleven patients had oral discoid lesions without involvement of the skin. The time of onset of the oral discoid lesions rnaged from 6 to 75 years with a mean of 41 years. The mean druation of the oral lesions was 4.2 years. Symptoms from the oral discoid lesions were present in 75% of the patients. The clinical appearance varied and some lesions were difficult to differentiate from oral leukoplakia or from the lesions seen in oral lichen planus. The oral discoid lesions were most often seen on the buccal mucosa, the gingiva, labial mucosa and vermilion border. The oral lesions were infected by yeasts in more than half of thepatients.

Adolescent↗

Antibodies against double-stranded DNA in patients with connective tissue diseases. Comparison between Crithidia luciliae kinetoplast immunofluorescence test and Farr technique.

Antibodies against double-stranded (ds) DNA were demonstrated by an immunofluorescence technique using Crithidia luciliae kinetoplast as antigen, and by means of the Farr technique. Both techniques were used simultaneously in 172 sera from patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), juvenile rheumatoid arthritis (JRA), temporal arteritis (TA) and from healthy controls. Comparable results were obtained with the two techniques. SLE patients with active disease had higher titres of IgA antibodies than patients with inactive disease. Of the patients with RA and JRA, 10% had significant titres of dsDNA antibodies. Patients with TA and normal controls had either no dsDNA antibodies in their sera or very low titres without complement-fixing properties.

Adult↗

Penicillamine-induced polymyositis-dermatomyositis.

Two patients with classical rheumatoid arthritis developed myopathy during treatment with penicillamine. In both patients, electromyography and muscle biopsies were indicative of polymyositis. In one patient, muscle enzymes were not examined at the appropriate time; in the other patient muscle enzymes were raised. This latter patient also had a rash and, in the dermal epidermal junction of pathological skin, granular deposits of immunoglobulin and complement were found. The myopathy subsided in both patients after withdrawal of penicillamine.

Action Potentials↗

Deposits of complement and immunoglobulins in dermal and synovial vessels in psoriasis.

Deposits of complement C3 and/or immunoglobulin were found in the vessel walls and/or at the dermal-epidermal junction in skin lesions of all of 11 patients with psoriatic arthritis and guttate psoriasis. Similar deposits were seen in 6 out of 15 patients with psoriasis vulgaris. Synovial tissue available from 2 patients revealed deposits in the vessel walls.

Complement C3↗

Levamisole-induced hypersensitivity.

A 73-year-old woman with rheumatoid arthritis was treated with Levamisole, 150 mg per day, on 2 days a week. Her arthritis improved, but she developed a severely itching rash, and the treatment was stopped after 6 months. Penicillamine was subsequently given and tolerated without skin complications. 15 months after regular Levamisole was stopped, she was given a single dose of 150 mg which provoked fever of 40 degrees C and rash. Thirteen punch-biopsy specimens were examined by direct immunofluorescence microscopy. During the Levamisole treatment, granular deposits of IgG and C3 were found at the dermal--epidermal junction. Subsequently, the deposits disappeared, but reappeared after Levamisole challenge. The patient's leukocytes were exposed in vitro to Levamisole, and 36% of the total histamine content in the basophils was released. Our results provide further evidence that Levamisole can cause type-I as well as type-III hypersensitivity.

Aged↗