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A Karlsson-Parra

Publications and source records attributed to A Karlsson-Parra.

61 records · Page 4Linked to original sources
PubMed1986

Phenotypic characterisation of peripheral blood lymphoid cells in people exposed to fibrous zeolite.

Among inhabitants of the village of Karain in Turkey there is an extremely high incidence of malignant mesothelioma, most probably due to exposure to erionite, which is a fibrous zeolite and similar in appearance and properties to asbestos. This mineral may be found in the dust in the village. To characterise possible disturbances in the immune system of people exposed to fibrous zeolite, a phenotypic characterisation of lymphoid cells in the peripheral blood of 74 immigrants to Sweden from Karain was performed. Compared with normal controls, the mean percentages of Leu 4+ cells (Pan-T) and Leu 3a+ cells ("helper/inducer" T cells) were significantly decreased, whereas the mean percentage of Leu 2a+ cells ("suppressor/cytotoxic" T cells) was normal, leading to a significant reduction of the Leu 3a/Leu 2a subset ratio. The percentage of B cells (Leu 12+ cells) was significantly increased, whereas the percentages of both HLA-DR+ and HLA-DQ+ cells were normal. The percentage of natural killer cells (NK) and killer (K) cells as defined by the monoclonal anti-Leu 7 and anti-Leu 11b were also normal. These findings indicate that exposure to fibrous zeolite causes a numerical imbalance between the two phenotypically different T cell subsets similar to that seen in asbestos exposed individuals.

Adult↗
PubMed1986

Peripheral blood T lymphocyte subsets in active rheumatoid arthritis--effects of different therapies on previously untreated patients.

Peripheral blood T lymphocyte subset levels were prospectively analyzed in previously untreated patients with active rheumatoid arthritis (RA) with different drug regimens. Before treatment the patient group had reduced numbers of Leu 2a+ lymphocytes compared with controls (p less than 0.001). During penicillamine and chloroquine treatment a marked reduction in absolute numbers of Leu 3a+ lymphocytes was seen (p less than 0.01), whereas treatment with nonsteroidal antiinflammatory drugs was characterized by increased absolute numbers of Leu 2a+ lymphocytes (p less than 0.02). Thus, there seems to be a predictable variation of T lymphocyte subsets in RA with certain drug regimens.

Adolescent↗
PubMed1984

Primary biliary cirrhosis--phenotypic characterization of immunocompetent cells in peripheral blood and liver tissue.

Circulating T-cell subsets have been characterized in 18 patients with primary biliary cirrhosis (PBC) using a simple immunoenzymatic staining method on stored and prefixed cell samples. Furthermore, a double immunoenzymatic method was used to study T-cell subsets and their relationship to HLA-DR+ cells in frozen sections of liver biopsies from 12 patients with PBC. In 10 cases blood and liver samples were taken simultaneously from the same patient. Patients with PBC of early histological stage showed an elevated absolute number of helper/inducer T-cells (Leu 3a+) and reduced relative percentages of suppressor/cytotoxic T-cells (Leu 2a+) compared with healthy subjects resulting in an elevated helper/suppressor ratio. Liver biopsies in PBC were dominated by helper inducer phenotype T-cells in all cases irrespective of histological stage, penicillamine treatment or the relative levels of circulating T-cell subsets. A relatively high amount of HLA-DR+ cells were seen, several of these in close approximation to T-cells.

Adult↗
PubMed1983

A simple immunoenzyme batch staining method for the enumeration of peripheral human T lymphocyte subsets.

A simple batch method was developed for enumeration of peripheral human T lymphocyte subsets by immunoenzyme staining of stored prefixed preparations of peripheral mononuclear cells on multiple well microscope slides. By this method the monoclonal antibodies Leu 1, Leu 2a and Leu 3a stained the same number of cells as by indirect immunofluorescence on suspended cells.

Antibodies, Monoclonal↗
PubMed1983

T-lymphocyte subsets and HLA-DR-expressing cells in rejected human kidney grafts.

This communication describes an immunohistochemical analysis of rejected human renal allografts. T-lymphocyte subsets were identified in frozen tissue sections, by Leu 1 (anti-'pan' T lymphocytes), Leu 2a (anti-'cytotoxic/suppressor' T cells), and Leu 3a (anti-'helper/inducer' T cells) monoclonal antibodies. In addition, HLA-DR-positive cells were identified by simultaneous labelling with heterologous anti-HLA-DR antibodies. T cells dominated the cellular infiltrates in acute cellular rejection. Leu-3a-positive cells were more numerous than Leu-2a-positive cells. The Leu-3a-positive cells usually appeared in clusters, whereas the Leu-2a-positive cells appeared scattered in the tissue. HLA-DR-positive non-T cells were found within clusters of T 'helper/inducer' cells. The cell pattern shares many features with the findings in delayed-type hypersensitivity reactions.

Antibodies, Monoclonal↗
PubMedDate not supplied

Detection of antinuclear antibodies by indirect immunofluorescence in dog sera: comparison of rat liver tissue and human epithelial-2 cells as antigenic substrate.

Rat liver sections and a human epithelial cell line (HEp-2) were compared as substrates for the detection of antinuclear antibodies (ANA) in the serum of normal dogs and dogs with suspected autoimmune disease, using a standard indirect immunofluorescence (IIF) technique. Antibody reactivity against rat hepatocyte nuclei was frequently found at low serum dilutions in normal dog sera. Using rat liver sections, a minimum significant positive titer, allowing negativity in more than 95% of normal dog sera, was found to be 1/100. With this titer, ANA positivity could be verified in 64 of 112 (57%) reanalysed serum samples from dogs with suspected autoimmune disease, earlier determined as ANA-positive. No reactivity against nuclei of HEp-2 cells was observed in any of the normal dog sera analyzed at a screening dilution of 1/25. Using this dilution as a minimum significant positive titer, 63 of the 112 (56%) re-evaluated serum samples were positive. These 63 samples were from the same dogs as the 64 samples that were positive on rat liver sections. Thus, the 2 methods of ANA-IIF detected a nearly identical population of dogs with suspected autoimmune disease once the level of significance of a positive titer was adjusted to > 95% specificity for each method. HEp-2 cells were found to be superior to rat liver cryostate sections as ANA substrate because of their low reactivity with normal sera, and the ease of discernment of the ANA fluorescence pattern. The recognition and documentation of specific pattern types may give clues to ANA subspecificities, which could prove useful if they are found to correlate with well-defined subgroups of immune mediated clinical diseases in dogs.

Animals↗