PubMed Health⌕ Search

Biomedical subjects

M Abinun

Publications and source records attributed to M Abinun.

11 recordsLinked to original sources
PubMed1996

Chronic mucocutaneous candidiasis. I. Altered antigen-stimulated IL-2, IL-4, IL-6 and interferon-gamma (IFN-gamma) production.

Patients with chronic mucocutaneous candidiasis (CMC) present with persistent infections with the opportunistic yeast Candida. Impaired cell-mediated responses to Candida have been documented in CMC patients, but the defect remains poorly understood. The importance of Th1 cytokines in resistance and Th2 in susceptibility to Candida infections has recently been demonstrated in murine models. In our studies we evaluated production of IL-2 and IFN-gamma (markers of Th1 type responses) as well as IL-4 and IL-6 (Th2 type markers) following stimulation with two kinds of Candida antigens (CAgs), polysaccharide antigens, tetanus toxoid and pokeweed mitogen. Our results demonstrate that CMC patients have impaired cytokine production upon in vitro stimulation with CAgs resulting in low or absent IL-2, increased IL-6 and either absent or increased IFN-gamma production. Cytokine production following stimulation by other antigens was unaltered. The overall cytokine-producing capacity assessed through mitogen stimulation was also intact. Addition of IFN-alpha or IFN-gamma to culture in an attempt to modify cytokine production did not have significant effects. Levels of soluble IL-6 receptors were not increased and could not account for increased IL-6 production. Our studies support the hypothesis that Candida antigens trigger a predominantly Th2 instead of a Th1 cytokine response in patients with CMC.

Adolescent↗
PubMed1996

Chronic mucocutaneous candidiasis. II. Class and subclass of specific antibody responses in vivo and in vitro.

Patients with chronic mucocutaneous candidiasis (CMC) succumb to persistent infections with the opportunistic yeast Candida. Impaired cell-mediated responses to Candida have been repeatedly reported while antibody responses were mostly found to be normal. The underlying defect remains poorly understood. It has recently been shown that CMC patients are also susceptible to infections with encapsulated bacteria, and may have associated IgG2 and IgG4 deficiency. Our previous studies demonstrated altered cytokine production in CMC patients. As cytokines can influence production and isotype of specific antibody, in 10 patients with CMC we measured the levels and isotype distribution of serum antibodies to Candida antigens (CAg), pneumococcal polysaccharide (PPS) and tetanus toxoid (TT) antigens. Peripheral blood lymphocytes were also stimulated in culture and the antibodies made in vitro were measured. Our data demonstrated that in vivo, CMC patients had very high levels of IgG and IgA CAg-specific antibodies. CAg-specific and PPS-specific IgG1 was markedly higher than in controls. Children but not adults with CMC had significantly lower levels of IgG2-specific antibody to CAg and PPS compared with age-matched controls. Patients had significantly higher levels of IgG3-specific antibody to all three antigens tested. These findings were in accordance with increased total IgG and IgG3 levels seen in CMC patients. In vitro, CMC patients, particularly children, did not respond as frequently to antigen stimulation as did their healthy controls. The level of specific antibody produced was also lower to all antigens tested, as was the amount of total immunoglobulins following antigenic and particularly mitogenic stimulation. Addition of interferon-alpha (IFN-alpha) or IFN-gamma to cultures had variable, sometimes marked, effects. Our results demonstrate that CMC patients manifest subtle alterations in specific antibody responses to CAg, PPS and TT, which are most pronounced in children. This may relate to altered cytokine production also seen in these patients.

Adult↗
PubMed1996

Disseminated BCG infection in severe combined immunodeficiency presenting with severe anaemia and associated with gross hypersplenism after bone marrow transplantation.

An infant with severe combined immunodeficiency (SCID) is described, who presented with severe anaemia and hepatosplenomegaly due to disseminated Bacillus Calmette-Guérin (BCG) infection involving the bone marrow, liver and spleen. After BMT, huge splenic enlargement occurred, presumably due to proliferation of engrafted donor lymphocytes, leading to severe hypersplenism. Peripheral blood cell consumption was resolved by splenectomy, but gradual loss of the marrow graft followed.

Anemia↗
PubMed1994

Focal glomerular sclerosis and nephrotic syndrome in spondyloepiphyseal dysplasia.

The association of a spondyloepiphyseal dysplasia and disproportionate short stature with focal glomerular sclerosis is reported in two girls. Renal disease manifested by proteinuria at the age of 2.5 and 11 years, leading to treatment-resistant nephrotic syndrome over 15 and 45 months, respectively. One patient went into end-stage renal failure shortly after nephrotic syndrome developed, the other died from sepsis. The association of spondyloepiphyseal dysplasia and focal glomerular sclerosis with nephrotic syndrome may represent a distinct disease entity.

Adolescent↗
PubMed1992

An unusual T-cell surface phenotype in vivo correlates with the failure to proliferate and produce IL-2 in vitro in a patient with common variable immunodeficiency.

Stimulation of T-lymphocytes derived from some patients with common variable immunodeficiency (CVID) syndrome results in defective proliferation. The underlying mechanism is related to the inability of stimulated cells to secrete IL-2 while the expression of IL-2 receptor (IL-2R) is normal. We have identified a patient whose peripheral T-cells failed to proliferate and secrete IL-2 upon stimulation. The addition of recombinant IL-2 restored proliferation. The defect did not seem to be caused by accessory cell failure since the patient's adherent cells produced IL-1 and IL-6, and addition of allogeneic irradiated cells did not induce proliferation. Stimulation of CVID T-cells with phorbol esters and Ca2+ ionophore induced both IL-2 secretion and proliferation, indicating the absence of a defect in the transcription and/or translation of the IL-2 gene. The patient's T-cells expressed high levels of CD3. The majority of T-cells expressed the CD38 molecule which is normally found on thymocytes or activated T-cells but not peripheral blood T-cells and HLA-DR, another activation marker. However, CD25 (the IL-2R) and CD1, a marker of more immature thymocytes, were not expressed. Finally, the patient's cells were sensitive to an in vitro corticosteroid treatment. The possibilities that this patient's T-cells represent anergic T-cells or not fully matured thymocytes are discussed.

ADP-ribosyl Cyclase↗
PubMed1988

Infantile cortical hyperostosis associated with the Wiskott-Aldrich syndrome.

A case report of an infant with the Wiskott-Aldrich syndrome and clinical and radiological features of infantile cortical hyperostosis (Caffey disease) is presented. This is the third case described of the association of these two rare disorders and gives further support to the role of an immunologic defect in the pathogenesis of infantile cortical hyperostosis.

Bone and Bones↗
PubMedDate not supplied

[Penicillin allergy in children].

Penicillin allergy in children is overdiagnosed and paediatricians, fearing the possibility of fatal anaphylaxis, seldom question a report that a child is allergic to penicillin. Laboratory tests to predict whether a patient will react to penicillin are unhelpful in routine clinical practice and skin tests themselves carry a significant risk of anaphylaxis and even death. A few simple inquiries can often exclude the diagnosis. However, a history of penicillin therapy associated with an immediate reaction suggests penicillin allergy.

Child↗