calcimycin and Hypergammaglobulinemia

The aim of this study was to investigate the effect of absent CD40-CD40 ligand interactions in patients with X-linked hyper-IgM syndrome (XHIGM) on the generation of Th1 and Th2 immunity. Whole blood from patients and sex- and age-matched controls was stimulated with phorbol myristate acetate (PMA) and calcium ionophore A23187 in the presence of Brefeldin A. After 5 h, cellular production of interferon-gamma, IL-4, tumour necrosis factor-alpha and IL-2 was measured by intracellular cytokine staining and flow cytometry. This method has been shown previously to preferentially activate memory T cells and in preliminary experiments cells making these cytokines were found to be predominantly CD45RO+. No differences in the proportion of T cells (CD3+) or T cell subsets (CD4+/CD8+) secreting these cytokines between XHIGM patients and age- and sex-matched controls were observed. In addition, production of IL-12 and IL-6 by monocytes in response to lipopolysaccharide and CD40 stimulation was equivalent in patients and controls. These results suggest that development of Th1 or Th2 memory cells in patients with XHIGM is unaffected by the absence of functional CD40 ligand. Rather, the susceptibility of these patients to intracellular pathogens, such as Pneumocystis carinii and Cryptosporidium parvum, is more likely to be due to an inability to activate the effector arm of the cellular immune response.

Topics: Adolescent; Adult; Calcimycin; Calcium; CD3 Complex; CD40 Antigens; CD40 Ligand; CD8-Positive T-Lymphocytes; Cell Differentiation; Child; Child, Preschool; Female; Humans; Hypergammaglobulinemia; Immunoglobulin M; Immunologic Memory; Infant; Ionophores; Lipopolysaccharide Receptors; Lipopolysaccharides; Lymphocyte Activation; Lymphokines; Male; Membrane Glycoproteins; Monocytes; Monokines; Syndrome; Tetradecanoylphorbol Acetate; Th1 Cells; Th2 Cells; X Chromosome

Nonactivated, fixed peripheral blood T cells (PBT) from healthy donors or patients with X-linked-hyper-IgM (HIGM) syndrome, or cloned T cells provided effective help for tonsillar B lymphocytes for induction of IgE or other immunoglobulin (Ig) isotypes. Helper activity was mediated by staphylococcal superantigens adsorbed to the T cells prior to fixation and required presence of IL-4 in the cultures. We demonstrated that the T cells neither expressed detectable CD40 ligand at the beginning of the superantigen treatment nor 24 h later. Phorbol ester (PMA) plus Ca-ionophore treatment efficiently induced CD40L. Such T cells did not, however, provide any help for B-cell activation in some experiments or stimulated only low responses in others. Antibodies against CD2, CD3 and ICAM-1 adsorbed to fixed T cells prior to coculturing inhibited helper activity. A soluble CTLA4 construct was also inhibitory. Our results suggest a pathway of B-cell activation independent of CD40L expressed on T cells.

Topics: Adult; B-Lymphocytes; Calcimycin; CD40 Antigens; Child; Genetic Linkage; Humans; Hypergammaglobulinemia; Immunoglobulin E; Immunoglobulin M; Ligands; Lymphocyte Activation; Palatine Tonsil; Staphylococcus; Superantigens; Syndrome; T-Lymphocytes, Helper-Inducer; Tetradecanoylphorbol Acetate; X Chromosome

We measured the in vitro production of interferon-gamma (IFN-gamma) in five cases of hyper-IgE syndrome (HIgE), induced by mitogens, calcium ionophores and phorbol ester. The biosynthesis of IFN-gamma was severely reduced or undetectable in HIgE, while it was near normal in most atopic patients. The in vitro spontaneous production of IgE was increased overall in HIgE patients, although no correlation was found with serum IgE levels. Recombinant interleukin-4 (IL-4) induced a further increase in IgE synthesis, and its effect was totally antagonized by recombinant IFN-gamma; the same pattern of response was also observed in atopic subjects with high production of IgE. IFN-alpha synergized with IL-4 on IgE synthesis, whereas recombinant IL-6 gave opposite changes in individual cases tested. We propose that IFN-gamma deficiency may be responsible for some of the features of HIgE patients, including IgE levels and infections.

Topics: Adolescent; Adult; Calcimycin; Child; Child, Preschool; Enzyme-Linked Immunosorbent Assay; Female; Humans; Hypergammaglobulinemia; Hypersensitivity, Immediate; Immunoglobulin E; Interferon-gamma; Interleukin-4; Lymphocyte Activation; Male; Middle Aged; Mitogens; Recombinant Proteins; Syndrome; Tetradecanoylphorbol Acetate

We have selected 11 patients with primary immunodeficiency disorders predominantly affecting T lymphocyte function (four with ataxia-telangiectasia (AT), four with common variable immunodeficiency (CVI) and one each with Wiskott-Aldrich syndrome, hyper-IgE syndrome and combined immunodeficiency) with defective gamma interferon (IFN-gamma) production in vitro. Induction with phytohaemagglutinin showed low interleukin 2 (IL-2) production concomitant with reduced IFN-gamma titres. However the addition of 10 U/ml of rIL-2 to cultures stimulated with staphylococcal enterotoxin B or galactose oxidase failed to restore IFN-gamma production in defective cases. IFN-gamma was titrated by both bioassay and immunoradiometric assay, ruling out the possible release of inactive or altered IFN-gamma molecules. Normal levels of IFN-gamma were found in patients of patients with AT, as well as in two AT and two CVI cases, demonstrating heterogeneity of defects within these syndromes. Soluble inhibitors or cellular suppression of IFN-gamma were not observed in mixing experiments. The possibility that defective interaction between accessory cells and T lymphocytes might account for the poor response to the inducing agents was ruled out as no IFN-gamma was produced using a calcium ionophore--which bypasses this step--in seven patients with absolute IFN-gamma deficiency.

Topics: Ataxia Telangiectasia; Calcimycin; Humans; Hypergammaglobulinemia; Immunologic Deficiency Syndromes; Interferon-gamma; Interleukin-2; Phytohemagglutinins; T-Lymphocytes; Wiskott-Aldrich Syndrome