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P Tauris

Publications and source records attributed to P Tauris.

At least 37 records · Page 2Linked to original sources
PubMed1985

Plaque-forming cell capability in the senescent.

The number of plaque-forming cells (PFC) developed in pokeweed mitogen (PWM)-activated unfractionated or T/B separated, 4:1 reconstituted cultures of peripheral blood lymphocytes (PBL) with well-characterized subpopulations obtained from healthy, aged subjects was compared to that of young blood donors. The absolute number of PBL in the aged was reduced by 36%, and the percentage of sheep erythrocyte-rosette-forming cells (E-RFC) by 27%, compared to the percentage obtained in young donors. The IgM-, IgG- and IgA-immunoglobulin (Ig) secretion was monitored with a protein A PFC assay. The number of PFC in PBL cultures of the aged was 58% of the number found in cultures of the young controls. The number of PFC generated in cultures of autologous irradiated T and untreated B cells showed a 104% increase in the aged whereas a 63% increase was obtained using cells from young individuals. Co-cultures of young B cells with untreated or irradiated young or aged T cells showed a significant rise in the PFC response in cultures with irradiated aged T cells, while an equal number of PFC was generated in cultures of young B cells with young or aged untreated T cells. Our results demonstrate a decreased number of PBL, especially T cells, an impaired B cell function and a pronounced enhancement of the PFC response in cultures of irradiated aged T cells and young or aged B cells, whereas the T helper function of untreated cells was found to be normal. The influence of monocytes on the PFC response did not differ in the two groups.

Aged↗
PubMed1985

Prolonged severe cholestasis induced by oxacillin derivatives. A report on two cases.

Two patients with osteomyelitis who developed reversible cholestatic jaundice during treatment with oxacillin derivatives are described. The clinical course as well as the biochemical pattern and the investigation of liver biopsy specimens enabled us to establish the diagnoses of drug-induced canalicular and hepatocanalicular cholestasis.

Adult↗
PubMed1984

Plaque-forming cell response of frozen human lymphocytes stimulated with pokeweed mitogen. II. Results obtained in cultures of irradiated T and untreated B lymphocytes.

The PFC capability of cryopreserved lymphocytes was tested after T/B cell separation and irradiation of the T cells. It is concluded that there is no selective loss of function of the involved subpopulations. Thus nitrogen-stored lymphocytes can safely be used in PFC assays after conventional separation and irradiation procedures.

Adolescent↗
PubMed1984

Evaluation of the acyclovir-induced modulation of the plaque-forming cell response of human peripheral blood lymphocytes.

The increasing use of the antiviral agent acyclovir has focused the attention to the possible side-effects on cellular and humoral immunological processes. The drug has preclinically been tested extensively but most investigations have been carried-out in animal models. The influence of acyclovir on the proliferation and the plaque-forming capability of pokeweed mitogen (PWM) activated cultures of unfractionated and isolated subpopulations from human peripheral blood lymphocytes (PBL), was investigated. These parameters were monitored with the 3H-thymidine incorporation technique and a protein A plaque-forming cell assay. Acyclovir had little inhibitory effect at physiological concentration whereas a detrimental decrease was noted at higher concentrations.

Acyclovir↗
PubMed1984

Plaque-forming cells in man. IV. Influence of acetylsalicylic acid in vivo and dexamethasone in vitro.

The influence of acetylsalicylic acid (ASA) and steroid (ST) on the number of plaque-forming cells (PFC) developed in pokeweed mitogen-activated cultures of peripheral blood lymphocytes (PBL) was investigated. Cultures of 10(6) PBL were established from blood samples of 16 healthy volunteers before and after intake of 2 g of ASA, and parallel cultures were supplemented with ST in vitro. The immunoglobulin secretion was monitored with a protein A assay. Our results show that pharmacological doses of ASA in vivo decrease the number of PFC by 41%, whereas the distribution of the subpopulations was unaltered. In cultures of PBL obtained before the intake of ASA and supplemented with 10, 50 or 100 micrograms/ml of dexamethasone the number of PFC was decreased by 50%, 41% and 44%, respectively. In cultures of PBL obtained after the intake of ASA and supplemented with 10, 50 or 100 micrograms of ST, the number of PFC was further decreased by 22%, 32% and 38%. The effects of ASA in vivo and ST in vitro were additive. The ratio of IgM, IgG and IgA PFC was unaffected by ASA and ST. It is suggested that the modulation of the PFC response induced by ASA and ST is mediated by the prostaglandin system.

Adult↗
PubMed1984

Plaque-forming cells in man. III. Generation of plaque-forming cells in allogeneic in vitro cultures of HLA-D/DR-incompatible B and T lymphocytes.

We have investigated the ability of allogeneic, irradiated T lymphocytes to induce proliferation and immunoglobulin (Ig) secretion in untreated peripheral blood B lymphocytes. Non-mitogen-activated co-cultures of isolated T and B lymphocytes from selected, full-house HLA-A,B and D/DR antigen-phenotyped donors were reconstituted in a ratio of 4:1. Proliferation was assessed on day 5-6 of culture by the 3H-thymidine incorporation technique, and the Ig secretion was monitored on day 6 with a protein A plaque-forming cell (PFC) assay. B lymphocytes were able to differentiate into PFC, and the number of plaques was significantly higher in cultures of cells with two HLA-D/DR antigen incompatibilities than in those sharing one antigen. In cultures of peripheral blood lymphocytes with no HLA-D/DR antigen difference, only a few PFC developed. HLA-A and B antigens had no influence on the response. Further, monocytes were not an absolute requirement for allogeneic activation of B cells. Sonicated T cells and culture supernatants from allogeneic T- and B-cells cultures were not able to induce PFC formation in B lymphocytes. Our results indicate that the PFC response obtained in non-mitogen-activated cultures of allogeneic T and B lymphocytes is dependent on HLA-D/DR disparity or on genes encoded in the HLA-D/DR region.

Antibody-Producing Cells↗
PubMed1984

Rapid screening for humoral immune deficiency.

A preliminary report on a fast, easy and inexpensive screen-test for the detection of humoral immune deficiency is presented. The method is based on the presence of heterophilic antibodies in normal human serum. Multitested normal individuals and immunodeficient patients showed a clearcut dichotomy in this screening procedure.

Agammaglobulinemia↗
PubMed1983

Plaque-forming cells in man. I. Basic technical results obtained with the protein A technique.

This paper describes the results obtained using an indirect protein A plaque-forming cell (PFC) assay applied to human peripheral blood lymphocytes (PBL) activated with pokeweed mitogen (PWM). A maximal response was obtained after 6 days of culture with regard to the three major classes of immunoglobulin (Ig) investigated. No difference was found between females and males. T and B lymphocytes mixed in ratios varying from 1:8 to 8:1 and unfractionated cells were investigated. A maximal PFC response of isolated lymphocytes was found in cultures of 1:4 T/B reconstituted suspensions of untreated cells, whereas the maximal response of untreated B and 2000-rad-irradiated T lymphocytes was found in cultures with a 4:1 T/B ratio. The number of plaques developed in cultures of unfractionated cells exceeded the response of 4:1 T/B reconstituted untreated lymphocytes but was far below the number of PFC developed in cultures of untreated B and 2000-rad-irradiated T lymphocytes. Normal donors developed approximately 70 X 10(3) PFC/10(6) cells. The viability was 85% after the incubation period. No difference was found in the PFC response of cultures of separated, reconstituted T/B lymphocytes set up in autologous and allogeneic combinations.

Adolescent↗
PubMed1983

Plaque-forming cells in man. II. Evidence of the existence of active suppressor cells in peripheral blood of normal plaque-forming cell non-responders.

When the immunoglobulin secretion of 172 normal healthy individuals was investigated with the protein-A plaque assay, 12 persons (7%) did not develop any plaque-forming cells (PFC) in cultures of pokeweed mitogen (PWM)-activated unfractionated peripheral blood lymphocytes (PBL), incubated for 6 days. The effect of irradiation on normal PFC responders and non-responders was also investigated; 2000-rad-irradiated non-responder T lymphocytes co-cultured with autologous untreated B lymphocytes restored the PFC response to normal levels. The evidence of a high level of suppressor activity in non-responder T lymphocytes was further demonstrated by the decreased PFC response of normal B lymphocytes co-cultured with untreated non-responder T lymphocytes.

Adult↗
PubMed1983

Functional studies on lymphocytes from two siblings with congenital hypogammaglobulinaemia.

Two brothers with hypogammaglobulinaemia classified as common variable immunodeficiency (CVID) were investigated for distribution of peripheral blood lymphocyte (PBL) subpopulations, DNA synthesis and plaque-forming cell (PFC) capability of pokeweed mitogen (PWM) activated autologous and allogenic cocultures. Both patients had a decreased absolute number of T cells and normal or elevated levels of surface immunoglobulin (SmIg) bearing cells. Isolated B cells cocultured with autologous or allogeneic 4000 r irradiated T cells responded subnormally to PWM monitored by the 3H-thymidine incorporation in microcultures whereas B cells cocultured with allogeneic untreated normal T cells proliferated normally. PBL from parallel macrocultures of unfractionated or T/B separated patients' cells were not able to produce plaques using a reversed haemolytic protein A assay. Addition of glucocorticoid to unfractionated PBL did not reverse the unresponsiveness. In allogeneic cocultures patients' untreated or 2000 r irradiated T cells induced a normal PFC response. Normal untreated T cells induced a reduced number of IgM- and IgG-PFC from patients' B cells but this response was almost eliminated using irradiated normal T cells. These results demonstrate a primary B cell defect in the patients and indicate an impaired cooperation between patients' B and T cells. Activation of patients' B cells to Ig secretion requires the presence of proliferating T cells.

Agammaglobulinemia↗
PubMed1983

The cellular immune response after splenectomy in humans. Impaired immunoglobulin synthesis in vitro.

The in vitro immune functions of peripheral blood lymphocytes have been studied in 70 splenectomized patients. 45 patients were splenectomized due to traumatic rupture of the spleen; in 22 of these patients residual splenic tissue was detected, employing a selective spleen scintigraphy. 14 patients were splenectomized due to hereditary spherocytosis and 11 patients due to immune thrombocytopenia or autoimmune haemolytic anaemia; they were all without ectopic splenic tissue. The study revealed that splenectomized patients have (i) an elevated number of blood lymphocytes, (ii) an elevated relative number of EA-RFC, but normal %s of E, EAC-RFC and SmIg positive cells, (iii) normal T-cell mitogenic responses induced by PHA, but enhanced responses induced by ConA and PWM, (iv) normal cell-mediated enhancement of the PWM-induced proliferative B-cell response, (v) no cell-mediated inhibition of the T-cell dependent and PWM-induced proliferative B-cell response and (vi) an impaired number of PFC after stimulation with PWM. The findings were unrelated to the cause of the splenectomies or to the presence of residual splenic tissue. It is possible that the impaired B-cell response as shown by the reduced number of PFC after stimulation with PWM may be of significance for the in vivo resistance to infections in splenectomized patients.

B-Lymphocytes↗
PubMed1983

Irradiated autologous T cells restore the in vitro responsiveness of PWM-activated peripheral blood lymphocytes from splenectomized individuals.

The in vitro immunoglobulin (Ig) secretion of pokeweed mitogen (PWM)-activated peripheral blood lymphocytes (PBL) from individuals splenectomized post-trauma was monitored with a protein A plaque-forming cell (PFC) assay. Cultures of unfractionated as well as reconstituted cultures of isolated erythrocyte rosette-forming (E-RFC)-positive (T lymphocytes) and E-RFC-negative (B lymphocytes) cells were established. Using unfractionated cells, the response was substantially reduced or absent, whereas cultures of autologous untreated B and 2000 rads irradiated T cells restored the response to normal levels. Normal T cells were not able to stimulate patients' B cells to Ig-secretion and patients' untreated T cells did not induce plaque formation in normal B cells, whereas irradiated patients' T cells induced development of approximately 50% of the response induced by normal irradiated T cells. These results indicate that the immunological defect in splenectomized individuals is not merely restricted to a high level of radiosensitive T cell suppression but also involves an impaired B cell function and T/B cell cooperation.

Adolescent↗