Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “IgA Deficiency”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 19 recordsLinked to original sources
PubMed1991

IgA deficiency.

IgA deficiency, the most common primary immunodeficiency, is a very heterogeneous clinical disorder which may be associated with a variety of infections, allergies, autoimmune disorders, gastrointestinal diseases, and genetic disorders. The central phenotypic feature of this immunodeficiency is a B cell differentiation arrest, the extent of which may determine the clinical variability. Integrity of the immunoglobulin genes and their expression by immature B cells in affected individuals suggests an immunoregulatory basis for the B cell arrest. Genetic studies imply that a susceptibility gene in or near the major histocompatibility locus may predispose homozygous individuals to a spectrum of antibody deficiencies which may range from isolated IgA deficiency to panhypogammaglobulinemia. Essential cofactors in the pathogenesis of IgA deficiency include environmental factors, such as certain drugs and viral infections.

B-Lymphocytes↗
PubMed1983

Altered expression of lymphocyte Fc alpha receptor in selective IgA deficiency and IgA nephropathy.

To study the expression of FcR specific for IgA (Fc alpha R) on human peripheral lymphocytes (PBL), PBL from normal donors were incubated with 300 to 500 micrograms/ml MOPC 315 IgA having anti-trinitrophenyl (TNP) antibody activity at 4 degrees C or 37 degrees C for 60 min. Under this condition, less than 2% of total cells could form rosettes with TNP-coated ox red blood cells (TNP-ORBC). When cultured with MOPC 315 IgA at 37 degrees C for 18 hr, however, there was a dose-dependent increase of the rosette-forming cells (RFC) binding TNP-ORBC. Because 15 to 20% of the total cells bound TNP-ORBC but not unsensitized ORBC, the rosette formation appeared to be due to the cytophilic binding of IgA to the cells. The binding of MOPC 315 IgA was competed by TEPC 15 IgA and human myeloma IgA, but not by murine myeloma proteins of other classes, indicating that the receptor is specific for IgA. Fc alpha R was induced on 15 to 20% of fractionated T and B cells, as well as on 15 to 18% of concanavalin A-(Con A) activated lymphocytes when cultured with IgA. The induction of the receptor was dependent on protein and RNA synthesis, but not on DNA synthesis as suggested by the sensitivity to metabolic inhibitors, such as mitomycin C, actinomycin D, puromycin, and cycloheximide. In five patients with selective IgA deficiency (serum IgA, 0 to 4 mg/dl), only 5.1% +/- 1.7 of PBL formed rosettes with TNP-ORBC after culture with MOPC 315 IgA, whereas 12.5% +/- 2.5 of PBL from normal donors (serum IgA, 90 to 330 mg/dl) formed rosettes. Fc alpha R was induced on more than 15% of the cells from these patients, however, when cultured with IgA in the presence of a conditioned medium obtained from mixed lymphocyte culture from two normal donors. The results suggested that the abnormality in the patients' PBL might be in the induction mechanism rather than in the number of precursor cells that could express Fc alpha R in the presence of IgA. On the other hand, Fc alpha R was induced on 10.4% +/- 1.5 of PBL from the patients with IgA nephropathy (serum IgA, 382 +/- 11 mg/dl) when they were incubated with IgA for 1 hr at 37 degrees C. Because Fc alpha R on normal PBL was not induced by 1 hr of incubation with IgA, it appeared that the receptor was already expressed in vivo on the cells of these patients.

Animals↗
PubMed1986

IgA deficiency in shar-pei dogs.

Two shar-pei puppies examined because of signs of sinopulmonary disease, one of which also had skin disease, had deficient IgA concentrations. Deficient serum IgA concentrations also were confirmed in 30 of 39 (76.9%) clinically normal adult dogs in two colonies of shar-peis. Both courses of disease--sinopulmonary signs and chronic skin disease and a benign clinical course--have been reported in human patients with IgA deficiency. Thus, the shar-pei might be an appropriate model for studying the immunopathology of IgA deficiency in man.

Animals↗
PubMed1989

IgG4 deficiency in IgA-deficient patients.

IgG subclass deficiency may be an important factor in the infection proneness of some IgA-deficient subjects. Although several studies on IgG subclass deficiency in IgA-deficient subjects have been reported, most have been unable to assess the incidence of IgG4 deficiency because the limitations of the assay methods used have often made a distinction between low normal and subnormal concentrations impossible. Having developed an enzyme-linked immunosorbent assay capable of measuring concentrations of all the IgG subclasses in healthy subjects of all ages and having established age-normal ranges for IgG subclasses using this assay, we measured IgG subclass concentrations in 73 IgA-deficient patients, the majority of whom were children with recurrent respiratory infections. The results showed that IgG4 deficiency occurred in 26% of the patients and was the most common IgG subclass deficiency found. IgG1, IgG2 and IgG3 deficiencies occurred, respectively, in 10, 12 and 8% of the patients. IgA-IgG4 deficiency occurred in 16% of the patients; IgA-IgG2-IgG4 in 4%; and IgG1-IgG2-IgG4, IgA-IgG1 and IgA-IgG2-IgG3 each occurred in 3%. Other subclass deficiencies or combinations of deficiencies were less frequent. Our results suggest that IgG4 deficiency even in the absence of IgG2 deficiency may be an important but hitherto largely unrecognized factor in infection proneness in some IgA-deficient patients.

Adolescent↗
PubMed1976

Familial clustering of selective IgA deficiency.

Serum IgA levels of 35 healthy IgA-deficient index cases, of their 180 first-degree relatives, and of 31 other family members were studied. IgA deficiency was detected in 7.2% of the first-degree relatives, which is significantly more than the 0.25% frequency of IgA deficiency in healthy Finnish blood donors. Subnormal serum IgA levels were found in additional 13 (7.2%) first-degree relatives. The familial clustering of IgA deficiency seemed to be controlled by multigenic factors. IgA-deficient persons and their family members were tested for antinuclear and antithyroid antibodies, for rheumatoid factor (by latex test) and for other anti-IgG antibodies (by Ripley test). Antibodies against bovine milk were also studied. The relatives of IgA-deficient persons did not have more of these antibodies than the controls. It is suggested that various serological abnormalities are a consequence of the IgA deficiency rather than of genetic defects per se.

Autoantibodies↗
PubMedDate not supplied

[Selective IgA deficiency].

Selective IgA deficiency may be defined as an inborn state characterized by a decrease of serum IgA levels below 8 IU/1 (approximately 5 mg/dl) which may be associated with clinical symptoms of disease. The frequency of this condition in the general population varies between 1 : 400 and 1 : 3000 in different countries. Patients with defects of chromosome 18, ataxia teleangiectatica and with connatal rubella syndrome have a high incidence of IgA deficiency. Inspite of the decrease in circulating IgA there are B-lymphocytes containing IgA molecules in the peripheral blood. Thus it has been concluded that transformation of B-lymphocytes into IgA bearing plasmacells is stunted by another mechanism. While small amounts of IgA may be released by transformed plasmacells the capacity of B-lymphocytes to mature into fully functioning plasmacells releasing normal amounts of IgA is defective. T-cells acting as suppressor cells for IgA differentiation have been demonstrated in peripheral blood and are a possible explanation for this phenomenon. The majority of individuals with IgA deficiency are healthy. Evaluations of increased susceptibility for infections have to consider the fact that 6 respiratory tract infections per year are the average for any preschool child. However a number of children with IgA deficiency suffer from recurrent bacterial infections such as sinusitis, bronchitis and pneumonia, usually responding well to antibiotic treatment. IgA deficiency has an established correlation with atopic disease. There is an 40 fold increase in incidence of allergies and autoimmune diseases such as rheumatoid arthritis, lupus erythematodes and thyroiditis in individuals with IgA deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoimmune Diseases↗
PubMed1979

IgA synthesis by peripheral blood mononuclear cells from normal and selectively IgA deficient subjects.

IgA secretion and intracellular IgA synthesis by PWM-stimulated peripheral blood lymphocytes from normal and IgA deficient subjects were measured by radioimmunoassay. Cultured lymphocytes from eleven out of twelve IgA deficient subjects had impaired or undetectable IgA production. Measurement of intracellular IgA showed that the defect was more basic than simply defective secretion by IgA plasma cells. Co-culture of lymphocytes from IgA deficient and normal subjects revealed defects in both the B and T cell populations of IgA deficient subjects. In one subject the defect was in the T cells, in another the B cells, and in two others both T and B cells were defective.

Animals↗
PubMed1992

Genetic and immunologic analysis of a family containing five patients with common-variable immune deficiency or selective IgA deficiency.

A family with 13 members included 2 subjects with selective IgA deficiency (IgA-D) and 3 subjects with common-variable immune deficiency (CVID), diseases which usually occur sporadically. Reciprocal combinations of B and T cells in vitro between one normal and two immune-deficient family members and normal subjects revealed that defective Ig synthesis was determined by the B cells, while the patient T cells functioned normally. Normal T helper and suppressor function was demonstrated even in one patient with CVID who developed a T-cell lymphoproliferative disorder associated with elevated IgM; this patient's B cells made only IgM in vitro. Immune deficiencies were inherited in this family in a pattern consistent with an autosomal dominant trait with incomplete penetrance. All the immune-deficient patients in this family possessed at least one copy of an MHC haplotype previously shown to be abnormally frequent in IgA-D and CVID: HLA-DQB1*0201, HLA-DR3, C4B-Sf, C4A-deleted, G11-15, Bf-0.4, C2-a, HSP70-7.5, TNF alpha-5, HLA-B8, and HLA-A1. The patient who developed the lymphoproliferative disorder was homozygous for this haplotype. Four immunologically normal members, one of whom was 80 years old, also possessed this MHC haplotype, indicating that its presence is not sufficient for disease expression. A small segment of another MHC haplotype associated with Ig deficiency in the population also occurred in this family, but it was not associated with immune deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1981

Transitory and persistent IgA deficiency. Reevaluation of 19 pediatric patients once found to be deficient in serum IGA.

In 21 out of 5181 serum samples tested between 1968 and 1977 IgA was not detectable. In this subsequent study, 19 individuals could be reinvestigated by clinical and laboratory methods. At reevaluation 26% showed high, 16% normal and 58% subnormal serum IgA. Late maturation of the IgA system therefore occurs frequently. Lack of secretory IgA was proven in 16% and the material used were tears: even in the group with subnormal IgA clinical manifestations are minimal. Development, compensatory mechanisms and criteria for a new definition of selective IgA deficiency are discussed.

Child↗
PubMed1992

Transfusion management of patients with IgA deficiency and anti-IgA during liver transplantation.

Severe anaphylactic or allergic reactions may occur during blood transfusion to patients who are IgA-deficient and have anti-IgA in their blood, particularly those with class-specific antibodies. These patients are a particular challenge to the hospital transfusion service when large volumes of blood components are required for transfusion support, as in liver transplantation. We have successfully provided blood components for 3 such patients undergoing liver transplantation. Red cells were washed manually or by automated technique. Platelets were washed manually. All plasma was from IgA-deficient donors. One patient's entire plasma requirements were supplied by autologous plasmapheresis. Serial determinations of IgA levels and anti-IgA titers in 1 patient demonstrated an abrupt fall in anti-IgA with the appearance of barely detectable amounts of IgA during the surgery. IgA-containing plasma cells were demonstrated in the biopsies of liver homografts of 2 patients following transplantation. IgA deficiency with anti-IgA can be successfully managed during liver transplantation with advance planning.

Adolescent↗
PubMed1986

Selective IgA deficiency.

Selective IgA deficiency is the most common form of immunodeficiency. Certain select populations, including allergic individuals, patients with autoimmune and gastrointestinal tract disease and patients with recurrent upper respiratory tract illnesses, have an increased incidence of this disorder. These patients have the unique ability to form various antibodies and auto-antibodies including anti-IgA antibodies. Failure of terminal differentiation of the B lymphocyte is the primary defect in IgA deficiency. Treatment should be directed toward the underlying disease associated with this immune disorder. These patients should be advised of the consequences of improperly administered blood or blood products.

Antibodies, Anti-Idiotypic↗
PubMed1992

Effects of serial plasmapheresis on serum IgA levels in IgA-deficient blood donors with IgA-suppressor T cells.

Seventeen IgA-deficient blood donors, without antibodies to IgA, underwent plasmapheresis four to eight consecutive times at intervals of 8 weeks or less to provide fresh-frozen plasma for patients with anti-IgA. Blood samples, drawn for analysis no more than 1 hour before plasmapheresis and again at the conclusion of each procedure, were analyzed for lymphocyte subpopulations and serum IgA levels. Five lymphocyte subpopulations, including natural killer cells, the suppressor-inducer CD4 subset, the suppressor-precursor CD8 subset, non-major histocompatibility complex (MHC)-restricted cytotoxic T cells, and CD5+ B cells, were all decreased significantly after plasmapheresis (p less than 0.05). In a subgroup of IgA-deficient donors with excessive IgA-suppressor T-cell activity, serum IgA increased to levels exceeding 0.05 g per L following the fourth consecutive plasmapheresis procedure. Serum IgA levels did not similarly increase in IgA-deficient donors without excessive IgA-suppressor T-cell activity or in controls without IgA deficiency. Our study shows the potential, in a subpopulation of IgA-deficient donors who undergo frequent plasmapheresis, for a transient increase in serum IgA to a level no longer considered IgA deficient.

Antibody Formation↗
PubMed1988

Serum IgA deficiency and anti-IgA antibodies in pernicious anemia.

Three pernicious anemia (PA) patients with selective IgA deficiency and anti-IgA antibodies in their sera were followed for over 3 years. After instituting therapy with cyanocobalamin there was a slight increase in the anti-IgA antibodies. After 1 year the titers of anti-IgA antibodies in the sera of these patients declined significantly as compared to the values before treatment (P less than 0.02), and after 2 years one patient had no measurable anti-IgA antibodies, yet no IgA appeared in the serum of any of the three. Further, in a medium with no anti-IgA the lymphocytes of these patients were not capable of producing IgA in vitro. Thus, the reason for the IgA deficiency in PA appears to be linked to the function of B cells rather than to anti-IgA antibodies.

Adolescent↗