PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Common Variable Immunodeficiency”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35Linked to original sources

Hereditary C2 deficiency associated with common variable immunodeficiency.

Homozygous C2 deficiency in a 19-year-old boy was associated with variable immunodeficiency manifested by marked hypoimmunoglobulinemia and impaired antibody responses, normal circulating B lymphocytes, and subnormal T-cell functions. Neither antilymphocytic autoantibodies nor chromosomal abnormalities were found. Serum immunoglobulin levels were within normal limits in his parents and brother who were heterozygous for C2 deficiency. The patient's lymphocytes were homozygous at the HLA-D locus but expressed an antigen different from DW2.

Adult↗

Functional analysis of lymphocytes from two patients affected by common variable immunodeficiency (CVI).

Two patients affected by severe hypogammaglobulinemia classified as CVI were studied. Both patients showed an increase in peripheral T cells and a normal or elevated number of surface immunoglobulin-bearing cells (sIg+); the T cell subsets showed a decrease of CD4 and an increment of CD8 cells with an inversion of the CD4/CD8 ratio. Patient peripheral blood mononuclear cells (PBMC) did not proliferate after Staphylococcus aureus Cowan I (SAC) activation. Moreover, patient PBMC were not able to differentiate into plaque - forming cells (PFC) either spontaneously or after pokeweed mitogen (PWM) stimulation. The immunoglobulin synthesis from patient PBMC stimulated in vitro by PWM was very little as compared to controls. When isolated patient B cells were cultured in the presence of exogenous B cell growth factor (BCGF) and BCGF plus anti-mu and anti-delta antibodies, no proliferation was observed. Taken together the results concerning B cell function of our CVI patients indicate the presence of an intrinsic defect of B cells. These cells are normal in number, but they are not able to leave the resting state, enter the activation state, proliferate and differentiate into Ig secreting cells. Moreover the alteration of the T cell subset proportions seems to suggest an impaired cooperation between B and T cells.

Adult↗

Peripheral blood lymphocytes of patients with common variable immunodeficiency (CVI) produce reduced levels of interleukin-4, interleukin-2 and interferon-gamma, but proliferate normally upon activation by mitogens.

Peripheral blood lymphocytes (PBL) of 11 patients with CVI produced reduced levels of interleukin-4 (IL-4) upon activation by mitogens as compared with those secreted by PBL of healthy donors. The interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) production by PBL of a series of 15 patients with CVI was also reduced. Decreased levels of IL-4 or IL-2 and IFN-gamma production were not only observed after activation by phytohaemagglutinin (PHA) at concentrations of 10 and 1 micrograms/ml, but also after activation by concanavalin A (Con A, 10 micrograms/ml). Longitudinal studies indicated that this defective lymphokine production was consistent upon testing periods up to 5 months. No correlation between reduced IL-4, IL-2 or IFN-gamma production was observed. PBL of patients that produced reduced levels of one lymphokine generally secreted normal levels of the other two lymphokines. Despite the reduced synthesis of the T cell growth factors IL-2 and IL-4, the proliferative responses of the PBL of the patients were in the normal range, which is compatible with the finding that IL-2 and IL-4 have synergistic effects on lymphocyte proliferation, particularly when one of these lymphokines is present at suboptimal concentrations. Since IL-2, IL-4 and IFN-gamma can act as B cell growth and differentiation factors, our data suggest that the reduced synthesis of these lymphokines may contribute to the deficient immunoglobulin production in patients with CVI.

Adolescent↗

Interleukin-4 suppresses immunoglobulin production by peripheral blood lymphocytes of patients with common variable immunodeficiency (CVI) induced by supernatants of T cell clones.

Supernatants of both CD4+ and CD8+ alloreactive T cell clones induced IgM, IgG and IgA synthesis by peripheral blood lymphocytes (PBL) of healthy donors in vitro. These supernatants were also tested on their capacity to induce immunoglobulin production by PBL of four patients with CVI and one patient with CVI and thymoma. A low degree of IgM, IgG and IgA production was induced in one patient with CVI. In the patient with CVI and thymoma, induction of IgG and IgA synthesis was in the normal range, whereas IgM production was reduced. In the three other patients only a low production of IgM was induced. Interestingly, pre-incubation of the PBL for 24 h with interleukin-4 (IL-4) suppressed immunoglobulin production both by PBL of the patients with CVI and healthy donors. The strongest inhibitory effects were observed on IgA synthesis. These data indicate that B cells of three patients with CVI can not be induced to switch to IgG or IgA producing cells in vitro. In contrast, B cells of the patient with CVI and thymoma were able to respond to the relevant B cell growth and differentiation factors present in the T cell clone supernatants, suggesting that the T cells of this patient may fail to produce these factors. However, the proliferative responses of the T cells to phytohaemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM), were normal in all five patients tested. In addition, the interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) production by PBL of the five patients was also in the normal range. Although only a small number of patients was tested, these results support the view that defects in both regulatory T cell functions and/or intrinsic B cell defects may contribute to the pathogenesis of CVI.

Adolescent↗