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Biomedical subjects

A Klajman

Publications and source records attributed to A Klajman.

At least 37 records · Page 2Linked to original sources
PubMed1986

T lymphocytes of rheumatoid arthritis patients show augmented reactivity to a fraction of mycobacteria cross-reactive with cartilage.

An acetone-precipitable fraction of Mycobacterium tuberculosis cross-reacts with human cartilage. Immune responses to this antigen were assessed in 34 patients with rheumatoid arthritis, 16 patients with degenerative joint disease, and 15 healthy controls. The RA patients differed from the other two groups in having more pronounced T lymphocyte responses to the antigen; their serum antibody levels were not higher. The responses of RA patients varied with duration of disease. In the first year (7 patients) T lymphocyte reactivity was increased in the synovial exudates of affected joints but not in peripheral blood, whereas the 19 with disease of 1-10 years' duration showed high reactivity in peripheral blood; in the 8 with disease for more than 10 years, lymphocyte reactivity did not differ from that in the patients with degenerative joint disease or the healthy controls. The observation that the three groups did not differ in their responses to streptococci and a T-cell mitogen indicates that reactivity of the RA patients to the mycobacterial fraction was specific. These results raise the possibility that bacterial antigens cross-reactive with cartilage proteoglycans may be relevant to the pathogenesis of RA.

Adult↗
PubMed1986

Resistant hypertension associated with a renin-producing ovarian Sertoli cell tumor.

A 17-year-old girl with refractory, but nonmalignant, hypertension and hypokalemia is presented. A state of primary hyperreninism and secondary hyperaldosteronism was found to exist, together with a renin-producing Sertoli cell ovarian tumor. Upon removal of the tumor, this patient attained both a normotensive and a normokalemic state. A brief review is given of renal and nonrenal renin-producing tumors.

Adolescent↗
PubMed1986

Generation of B suppressor cells by phytohaemagglutinin.

Activation by phytohaemagglutinin-P (PHA-P) of B cells from peripheral blood of healthy subjects generated B suppressor cells which inhibited allogeneic mixed lymphocyte reactions (MLR) and PHA-induced DNA synthesis. Their action was direct, that is, not mediated through the induction of T suppressor cells. The finding that B cells can be induced by PHA to become highly effective suppressor cells may have important clinical and experimental implications.

B-Lymphocytes↗
PubMed1985

Interleukin-2 production and activity in aged humans.

Peripheral blood mononuclear cells (PBMC) from aged humans were found impaired in their ability to mount T mitogen induced proliferative responses and NK cell activity. The production of IL-2 in response to PHA has also been found decreased in the aged subjects. When the data from IL-2 production and cellular responsiveness of aged and young groups were pooled for regression analysis, a significant correlation was found both for mitogenic responses and NK activity. The reduced proliferative responses and NK cell activity can be enhanced by exposing them to exogenous IL-2. However, they were not fully reconstituted to the levels achieved in PBMC of the young subjects supplemented in vitro with IL-2. This would indicate that the reduced cellular responsiveness in aging may be related both to a defect of IL-2 receptor expression on T cells of aged subjects and to an impairment in the endogenous IL-2 synthesis in the aged individuals.

Adult↗
PubMed1985

Arthritis induced by a T-lymphocyte clone that responds to Mycobacterium tuberculosis and to cartilage proteoglycans.

Adjuvant arthritis characterized by chronic inflammation of the joints of rats is induced by immunization to Mycobacterium tuberculosis. To learn how autoimmune arthritis may be caused by a microbial antigen, we isolated a T-lymphocyte clone specific for M. tuberculosis antigens that was strongly arthritogenic. We now report that the clone recognized, in addition to M. tuberculosis antigens, antigens present in human synovial fluid, medium of chondrocyte cultures, and proteoglycans purified from cartilage. These observations indicate that the target antigen for the arthritogenic clone resides in the proteoglycan component of cartilage. As this arthritogenic clone shows specificity for both a M. tuberculosis antigen and a cartilage constituent we conclude that disease is probably caused by antigenic cross-reactivity. Thus, an autoimmune disease may be triggered by structural mimicry between antigens in the environment and self-antigens in the individual.

Animals↗
PubMed1984

Kaposi's sarcoma and angioimmunoblastic lymphadenopathy.

Kaposi's sarcoma (KS) and angioimmunoblastic lymphadenopathy (AILD) are exceptionally rare neoplastic diseases, although the former has recently been more frequently reported among certain populations, and is lately a topic for extensive medical and investigational interest. This case is unique in that it describes an association between KS and AILD. Such an association raises the question of a common pathogenic mechanism. The authors believe that predisposition to each of both diseases may be related to acquired immune deficiency which in turn may be induced by specific viral infections.

Aged↗
PubMed1984

In vitro effects of 4-hydroperoxycyclophosphamide on concanavalin A-induced human suppressor T cells.

Treatment in vitro of human peripheral blood lymphocytes (PBL) with ConA induced the generation of suppressor cells which inhibited T cell blastogenic response to ConA and of allogeneic response in the mixed lymphocyte reaction (MLR). Treatment of PBL with 4-hydroperoxycyclophosphamide (4-HPCy) before incubation with ConA markedly decreased the generation of suppressor cells by ConA. The effect of 4-HPCy on generation of suppressor cells was more pronounced in the test of ConA stimulation than in the MLR. Treatment with 4-HPCy had no effect on suppressor cells already induced as shown by incubation of PBL with 4-HPCy after incubation with ConA.

Cells, Cultured↗
PubMed1983

The prevalence of antibodies to histones induced by procainamide in old people, in cancer patients, and in rheumatoid-like disease.

Antibodies to histones were found to be most commonly responsible for the positive antinuclear antibody (ANA) test in asymptomatic patients treated with procainamide, in old people, in patients with neoplastic diseases, and in young women affected with a rheumatoid-like disease. Only in a very few patients were antibodies to dDNA and nucleoproteins demonstrated. Antibodies to nDNA were not found. The antibodies to histones were demonstrated by two methods: absorption of ANA-positive sera with a histone solution and subsequent performance of an ANA test; and acid elution of histones from thyroid sections followed by histone reconstitution.

Adolescent↗
PubMed1983

Autologous mixed lymphocyte reaction in man: further characterization of responding cells.

Experiments were performed to determine the type of cells undergoing thymidine incorporation in 7-day autologous mixed lymphocyte reactions (AMLR). Peripheral blood mononuclear cells (PBM) were separated into B cells, T cells, B + Null cells and T + Null cell-enriched populations. Cells were cultured in various combinations. Monocytes were removed to determine their influence on AMLR. The main thymidine-incorporating cells in cultures were shown to be Null cells and to a lesser extent T cells. Monocytes were found to have a more pronounced suppressor effect on stimulation of T cells by non-T cell populations in younger individuals than in the elderly. Whether Null cells undergo a spontaneous blastogenesis in culture or are stimulated by T or B cells, could not be answered by the present investigation.

Adult↗
PubMed1983

Cellular and humoral suppressor activity induced by concanavalin A-stimulated human fetal liver cells.

Incubation of human fetal liver cells (HFLC), obtained from 8-12-week-old fetuses, with mitogenic doses of Concanavalin A (Con A) resulted in generation of a population that could suppress alloantigen-induced lymphoproliferation. The supernatant media in which these cells were activated suppressed DNA synthesis, both in mitogen and alloantigen induced peripheral blood lymphocyte cultures. Suppression was achieved only when the Con A-activated cells or the supernatants were added during the early stages of sensitization. Treatment of the cells with mitomycin C after Con A activation did not alter their ability to mediate suppression. This study indicates the presence of suppressor or presuppressor cells in the liver in the early period of fetal life. If the suppressor activity of HFLC in vitro is also induceable in vivo, it may contribute to the fetal defense mechanism against maternal rejection.

Cells, Cultured↗
PubMed1982

Evaluation of bone marrow granulocyte reserves in neutropenic and nonneutropenic Yemenite Jews.

The bone marrow granulocyte reserves of 10 Yemenite Jews with hereditary neutropenia were estimated by measuring the maximum peripheral blood granulocyte increment after the administration of 40 mg prednisone. The control group consisted of 11 nonneutropenic Yemenites and 15 non-Yemenite Jews with normal peripheral blood neutrophil counts. The mean peripheral blood granulocyte increment in the neutropenic and nonneutropenic Yemenites was significantly less than in the non-Yemenite Jews. There was no significant difference in the response of the two Yemenite groups.

Adult↗