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A Ruiz-Arguelles

Publications and source records attributed to A Ruiz-Arguelles.

24 records · Page 2Linked to original sources
PubMed1980

Heterogeneity of the spontaneously expanded and mitogen-induced generation of suppressor cell function of T cells on B cells in systemic lupus erythematosus.

Eighty percent of 31 untreated patients with systemic lupus erythematosus (SLE) had abnormalities in their spontaneously expanded and/or Con-A-induced suppressor cell function, but the association of defects detected with both systems was only 68%. Loss of spontaneous suppression related positively to disease activity (r = 0.641) and the number of T gamma cells (r = 0.624) whereas Con-A-induced suppression correlated negatively with disease activity (r = -0.456) and the number of T gamma cells (r = 0.089). Incubation of mononuclear cells from SLE patients in antiribonucleoprotein IgG caused further loss of suppression in some, but not all, instances. The suppressor cell dysfunction found in SLE may result from diverse mechanisms, including a basic defect in the generation of suppressor cells and the abrogation of suppressor function by autoantibodies.

Adult↗
PubMed1979

Antibody penetration into living cells. II. Anti-ribonucleoprotein IgG penetrates into Tgamma lymphocytes causing their deletion and the abrogation of suppressor function.

We have previously shown that an anti-ribonucleoprotein (RNP) IgG can penetrate into live human mononuclear cells (MNC) having receptors for the Fc portion of IgG. Because T cells with such receptors (Tgamma cells) seem to behave as suppressor cells in immune regulation and because this suppressor function is diminished in diseases where antinuclear antibodies appear, we considered the possibility that antinuclear IgG antibody could penetrate Tgamma cells and affect them. Herein we show that fluorescein-labeled anti-RNP IgG can penetrate into Tgamma cells, enriched by either mitogenic stimulation or separation with a subpopulation of T cells with low affinity for sheep erythrocytes. Incubation of MNC with anti-RNP IgG before carrying out the separation procedures resulted in apparent loss of Tgamma cells at the end of separation. To confirm that deletion had actually occurred, we performed a cytotoxicity assay using 51Cr-labeled T cells. Anti-RNP IgG had a significantly higher cytotoxic effect that normal IgG on T cells, particularly on those with low affinity for sheep erythrocytes that include most Tgamma cells. Suppressor cell function studied in a system where it was expanded, by either 7-day culture or incubation with concanavalin A, and detected in a reverse plaque-forming cell assay with rabbit anti-human immunoglobulin-developing antibody was found to be abrogated by the addition of anti-RNP IgG to the suppressor function-expanding cultures. Controls in Ig-free medium, or medium supplemented with normal human IgG, aggregated normal human IgG, BSA-anti-BSA immune complexes, or F(ab')2 fragments of the anti-RNP IgG, did not abrogate suppressor cell function. This indicates that the abrogation of suppressor cell function by anti-RNP IgG is due to its penetration into Tgamma cells. Suppressor cell loss and/or dysfunction caused by penetration of antinuclear antibodies into Tgamma cells may lead to the self-perpetuation of autoimmune disease.

Animals↗
PubMedDate not supplied

Flow cytometry: its applications in hematology.

The techniques of flow cytometry are becoming more and more important for the clinical hematology laboratory. No longer a novelty confined to a few specialized institutions as it was 10 years ago, flow cytometry has blossomed into a mature discipline. The methodology is well-known, the mechanical apparatus is readily available, and the role it plays in clinical hematology is increasingly appreciated. The burgeoning number of scientific articles devoted to this topic attests to the interest it has aroused as a tool for both medical research and patient care. In fact, more than a thousand such papers are now published each year and it would be impossible to deal with all the methodologies and applications of FCM currently utilized or under development. Throughout this paper four relevant hematologic fields are briefly discussed, in which FCM appears to be of great help at present: the immunophenotyping of leukemias and lymphomas, the measurement of proliferative activity and DNA ploidy in hematological malignancies, the detection of drug resistant leukemic cells and the use of FCM in the study of platelets.

Flow Cytometry↗