PubMed Health⌕ Search

Biomedical subjects

J M Zabay

Publications and source records attributed to J M Zabay.

32 records · Page 2Linked to original sources
PubMed1985

Peripheral T-cell lymphoma. A clinical, histologic, and immunologic study of five cases.

The authors describe five white patients with peripheral T-cell lymphoma. Four patients were older than 65 years. All cases presented with a short clinical course and advanced stage at the time of diagnosis. Clinical manifestations included asthenia, weight loss, peripheral and abdominal lymphadenopathy. One case showed tonsillar involvement and subcutaneous lymph node enlargement; hepatomegaly was present in four cases, two of them with splenomegaly. Only one case presented peripheral lymphocytosis and antibodies to human T-leukemia virus. Although three cases were classified as diffuse mixed lymphomas and two as poorly differentiated lymphocytic lymphomas, there were some common characteristics: diffuse infiltration by different proportions of small lymphoid cells and large immunoblasts, some of them multinucleated and similar to Reed-Sternberg cells; accumulation of histiocytes, plasmacytosis, eosinophilia, venular proliferation and compartmentalization were also found. Bone marrow infiltration was observed in two patients. Results of monoclonal markers showed four cases to be OKT4+ and the other OKT8+. The morphologic and immunologic characteristics of these patients were typical and similar to those reported from other geographical areas.

Adult↗
PubMed1985

Abnormal B cell function in haemophiliacs and their relationship with factor concentrates administration.

The present study was performed to evaluate B cell function in haemophiliacs. Spontaneous and pokeweed mitogen (PWM)-induced immunoglobulin (Ig) production was determined by ELISA in the supernatants of cultured peripheral blood lymphocytes (PBL) from 14 haemophiliacs and 17 normal donors. Spontaneous IgM, IgA and IgG production was three times higher in patients than normal controls, while PWM-induced IgM, IgA and IgG production was markedly reduced in patients compared to normal donors (P less than 0.025). Allogeneic co-cultures of haemophiliacs and normal B plus T cell fractions revealed that these results are due to a defect of the patients' T cell depleted fraction. These abnormalities were not found in three patients who had received no clotting factor concentrates for at least 1 year prior to the study. Additionally, the annual amount of clotting factor concentrates received by treated patients correlates well with the enhancement of spontaneous Ig production (r = +0.688, P less than 0.02), the decrease of PWM-induced Ig secretion (r = -0.655, P less than 0.02), and the elevation of serum IgG levels (r = +0.610, P less than 0.05). These findings suggest that the administration of clotting factor concentrates play an important role in the altered B cell function in haemophiliacs.

Adult↗
PubMed1984

Disorders of regulatory T cell function in patients with the Wiskott-Aldrich syndrome.

Three patients with the Wiskott-Aldrich syndrome were studied. One of them had no past history of relevant infections. The other two presented different degrees of humoral and cellular immunodeficiency and their T cells in vitro showed a defect in regulatory activity of Ig production in PWM stimulated cultures. This defect was not observed in the third patient. All three had normal numbers of B cells, producing normal amounts of Ig in vitro when co-cultured with normal T cells. It is suggested that the immunoregulatory T cell abnormality might play an important role in the pathogenesis of the humoral immunodeficiency.

B-Lymphocytes↗
PubMed1983

Cellular basis of hyper IgM immunodeficiency.

Six patients with primary hypogammaglobulinaemia and hyper IgM were studied. All showed very low serum IgG and IgA concentrations. The in vitro pokeweed-mitogen (PWM)-induced immunoglobulin (Ig) production, including IgM, by their peripheral blood lymphocytes was low. Even when patients' B cells were cocultured with normal T cells, IgM production did not reach normal levels. These results and studies of Ig class on the surface of B lymphocytes point to a maturation arrest of these cells. T cells from all but one patient helped very little Ig production by patients' or normal B cells. Similar numbers of these T cells did not suppress Ig production by normal T plus B cells. Therefore a defect in T cell help for IgM, IgG and IgA was seen in most patients, in addition to the B cell abnormality.

Adult↗
PubMed1983

[Purine nucleoside phosphorylase deficiency. Report of two cases].

Two brothers with a PNP deficit are reported. The first case presented recurrent upper respiratory infections and died of a sepsis by pseudomonas. The second one was diagnosed when he was six months old and remains asymptomatic. Immunologic tests revealed a deficit of T cell mediated immunity. Treatment consisted on radiated erythrocytes transfusions because HLA compatible donors were not available.

Antibody Formation↗
PubMed1982

B cell hyperactivity and abnormalities in T cell markers and immunoregulatory function in a patient with nucleoside phosphorylase deficiency.

We describe a 2 year old girl with nucleoside phosphorylase (PNP) deficiency, who had low blood T cell numbers and T lymphocyte blastogenic response to mitogens, hypergammaglobulinaemia, high titres of antibodies to many common antigens, various autoantibodies, a monoclonal IgM-kappa protein, an increased frequency of mature Ig containing blood B cells and a high production of Ig in vitro in unstimulated cultures. E rosetting cells showed faint or no immunofluorescence staining with monoclonal antibodies directed against T cell membrane antigens. In vitro Ig production in response to pokeweed mitogen was defective, and no T cell helper or suppressor activity was observed. It is suggested that the immunoregulatory deficiency might have caused the B cell hyperactivity.

Antibodies↗
PubMed1982

Functional assessment of T and B lymphocytes in patients with selective IgM deficiency.

Two patients with selective IgM deficiency were studied. Both presented with dermatitis, chronic diarrhoea, recurrent respiratory infections, failure to thrive, elevated serum IgE levels and in vivo impairment of antibody production. No phagocytic or complement abnormalities were found. B lymphocytes with surface IgM were present in normal or high percentage in peripheral blood, and produced normal amounts of IgM in vitro when co-cultured with normal T cells. Patients' T cells did not show excess suppressor function in vitro but had a decreased helper activity for IgM, IgG and IgA production. It is suggested that both patients have an extensive humoral immune deficiency that might be caused by the immunoregulatory T cell defect.

B-Lymphocytes↗
PubMedDate not supplied

[Intrathecal synthesis of IgG evaluated using different formulas: importance of multivariate analysis in the diagnosis of multiple sclerosis].

INTRODUCTION: Synthesis of IgG is useful data for the diagnosis of multiple sclerosis, and different formulas, both direct and indirect, are used to quantify this. We analyze these formulas with the objective of finding whether certain combinations of them would give better results than the individual formulas on their own. PATIENTS AND METHODS: We studied the cerebrospinal fluid of 45 patients with neurological disorders and determined the results of the two formulas which are most effective, according to some studies (Reiber's formula and IgG index) together with a direct formula (IgG ratio) and another indirect formula (the 'classical' formula of Tourtellotte). RESULTS: The IgG index was, in general, the formula which best differentiated between patients with multiple sclerosis and persons with other neurological disorders. CONCLUSIONS: We found a tendency which supported the original hypothesis that it is possible to use combinations of formulas to obtain better results than individual formulas. This fact may serve as a basis for further studies in which different combinations are tested, including analytical and clinical data, and this may be of use in the diagnosis of multiple sclerosis.

Biomarkers↗
PubMedDate not supplied

[Comparison between automated histamine liberation in whole blood and in isolated cells].

The classic histamine release test involved washing and isolating of leukocytes from heparinized whole blood. Siraganian automatized the extraction procedure, working initially with isolated leukocytes in Tris-human serum albumin-Ca++Mg++ buffer, with optimal results. One year later, he described a continuous flow system that permitted the study of whole blood from atopic patients. This method was easier to perform since the isolation of the white blood cells is no longer necessary. On the other hand, the results working with whole blood seem to be better than with isolated leukocytes. We have published modifications of the continuous flow technique, working also with whole blood. Our results agree with those of Siraganian and others. An alternative to working with whole blood or isolated cells in synthetic buffers could be the use of autologous diluted plasma. In this way, the cells are centrifuged and the plasma poured off. The plasma can be used for other determinations, such as RIA, ELISA, etc. The blood is reconstituted to its original volume with a PBS-Ca++Mg++ buffer and processed as described. The results using the whole blood and "washed cells" were very similar. But in some cases we found positive histamine release in "washed leukocytes" but not in whole blood. This striking phenomenon can be explained by the presence in plasma of blocking non-IgE antibodies. If this is the case, the removal of approximately 85% of the plasma will also lead to the disappearance of the 85% of these blocking antibodies. On the other hand, all the positive results obtained using whole blood have been confirmed using "washed cells". Therefore, the use of "washed cells" has several advantages with respect to whole blood assay or leukocyte isolation.

Allergens↗