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At least 19 recordsLinked to original sources
PubMed1979

Hyper immunoglobulin M immunodeficiency. (Dysgammaglobulinemia). Presence of immunoglobulin M-secreting plasmacytoid cells in peripheral blood and failure of immunoglobulin M-immunoglobulin G switch in B-cell differentiation.

The peripheral blood lymphocytes of nine patients with hyper immunoglobulin (Ig)M immunodeficiency were studied in an attempt to define the cellular basis of this disorder. B cells were normal in number but qualitatively abnormal in all patients. Approximately one-half of the B cell consisted of small lymphocytes (7-9 mum in diameter) bearing surface IgM and IgD, as well as C3 receptors. These cells were driven to secrete IgM but not IgG after in vitro stimulation by pokeweed mitogen. In the blood there were also large lymphocytes (10-14 mum in diameter) that possessed surface as well as intracytoplasmic IgM but lacked C3 receptors. These cells spontaneously secreted large amounts of IgM in vitro and on electron microscopy were found to be rich in rough endoplasmic reticulum. Such a subpopulation of lymphoid cells was not detected in normal peripheral blood and was unique for all patients with hyper IgM immunodeficiency studied.T cells from all patients were normal in number and in function both in vivo and in vitro and were able to generate adequate T-cell help to support IgG synthesis by normal B cells. No evidence was obtained for T cells capable of suppressing normal IgG synthesis in any of the patients after coculture with normal peripheral blood lymphocytes. The defect in hyper IgM immunodeficiency is intrinsic to B cells, which fail to switch from IgM to IgG synthesis.

Adult↗
PubMed1985

Effect of colostral immunoglobulin G1 and immunoglobulin M concentrations on immunoglobulin absorption in calves.

Twenty-three calves were fed colostrum at 110 ml/kg body weight divided into two feedings at 1 and 13 h of age. The concentrations of immunoglobulins were measured in the colostrum fed and in the calves' sera following colostrum feeding. Apparent efficiency of immunoglobulin absorption was calculated for each calf. Significant negative correlations between efficiency of absorption and mass of immunoglobulin fed were observed for both immunoglobulins. A separate group of 225 calves born on a commercial dairy were fed 2.84 L of colostrum by 4 h of age. Concentrations of immunoglobulin G1 in the colostrum fed and in the calves' sera at 48 h were measured. Negative correlation was observed between the efficiency of absorption and the mass of immunoglobulin G1 fed. These results suggest a physiologic limitation to the mass of immunoglobulin that can be absorbed to serum from a given volume of colostrum. No indication of a selective immunoglobulin absorption mechanism was observed.

Animals↗
PubMed1990

Cells and mediators which participate in immunoglobulin synthesis by human mononuclear cells. III. Null cells secrete a factor(s) (human immunoglobulin synthesis/secretion-facilitating factor) that can replace the null cells in the synthesis of immunoglobulin by cultured B cells.

In the accompanying communication, it was demonstrated that the null cells, the TM cells, monocytes and PWM are all obligatory participants in the synthesis and secretion of immunoglobulins by human B cells in culture. Here we demonstrate that the null cells secrete a factor, referred to as human immunoglobulin synthesis/secretion-facilitating factor (HISFF) that can replace the null cells in the cultures. HISFF is distinct from the known T cell-derived interleukins. HISFF functions in an HLA-unrestricted fashion since it can facilitate the synthesis and secretion of immunoglobulins by allogeneic B cells. The null cells cultured with TM helper cells and PWM required monocytes in the culture in order to secrete HISFF. Furthermore, B cells cultured with TM cells in medium containing HISFF, monocyte-derived factors and PWM nevertheless required monocytes in order to respond to the HISFF signal. Thus, the monocyte plays a pivotal role in the secretion of and response to HISFF. Normal levels of immunoglobulin were synthesized even when HISFF was added to the cultures of B cells, TM cells and monocytes, in the presence of PWM, as late as day 6 of the 7 day culture. We conclude that the null cells participate in immunoglobulin synthesis by the B cells by secreting a soluble mediator, HISFF, capable of replacing the null cells in the culture; and that the HISFF signal is the last signal received by the B cell before it begins to synthesize and secrete immunoglobulins.

B-Lymphocytes↗
PubMed1989

Polyclonal hyper-immunoglobulin G1(A1) syndrome. Evidence for a dominant immunoglobulin production regulator within the human immunoglobulin heavy chain gene complex.

The hyper-IgG1(A1) syndrome entails a polyclonal selective increase of the serum levels of immunoglobulin (Ig) G1 and to a lesser extent of IgA1; this is not mediated by malignancy, infectious or autoimmune diseases or environmental agents. In three generations of a family, all the affected individuals carried an immunoglobulin heavy chain (IgH) allele distinguished by restriction fragment length polymorphism analysis; the IgH allele was not present in non-affected family members. A 32:1 chance for the linkage of this rare IgH haplotype with the hyper-IgG1(A1) syndrome in the family argues for a dominant regulator located at the human IgH locus having a selective influence on the production of IgG1 and IgA1.

Female↗
PubMed1988

Immunoglobulin deficiency with increased immunoglobulin M in three siblings: effect of long-term immunoglobulin therapy.

Diagnosis of immunoglobulin deficiency with increased IgM (hyper-IgM syndrome) was made in three siblings (two girls and a boy) on the basis of history, physical findings, and laboratory data. The prominent clinical findings were recurrent viral and bacterial infections of the respiratory tract. The most severe infections affected the male patient, who died at the age of 8 years. Family history and the lack of clinical signs in the parents and relatives indicated no immunodeficiency which, together with the occurrence of the disease in both sexes, indicated an autosomal recessive inheritance. The two female patients (18 years old and 3 years old) have been treated with intravenous acid-treated immunoglobulin for 2 years, resulting in significant clinical improvement with respect to the frequency and severity of infections.

Adolescent↗
PubMed1968

Immunoglobulins in NZB-BL mice. I. Serum immunoglobulin levels and immunoglobulin class of erythrocyte autoantibody.

Determination of serum immunoglobulin levels in NZB and normal mice has indicated that an elevation of the gammaM-globulin level occurs in NZB mice. This can be demonstrated in young NZB mice well before other autoimmune manifestations are observed. A slight elevation of gammaM-globulin was also observed in NZB hybrid mice. Erythrocyte autoantibodies were analyzed by the direct Coombs' test with specific antiimmunoglobulin reagents. Autoantibodies in NZB mice can be of all immunoglobulin classes, although predominantly of gammaG(1)-class. In (NZB x NZC)F(1) hybrid mice, although Coombs' positivity develops around the same age as in NZB mice, there is a greater restriction of the autoantibodies into gammaM- and gammaG(1)-classes. Preliminary attempts to quantitate immunoglobulins coating NZB red cells have shown that there are approximately 400 molecules of gammaM and 5000 molecules of gammaG-globulin per NZB mouse red cell.

Animals↗
PubMed1975

Persistence of rubellavirus-specific immunoglobulin M and immunoglobulin A antibodies: investigation of successive serum samples with lowered immunoglobulin G concentration.

The persistence of rubellavirus-specific immunoglobulin (Ig) M and IgA antibodies has been studied in seven patients with primary postnatal rubella infections. Successive blood samples obtained over a period of several years after the onset of disease have been investigated, employing the fluorescent antibody technique and the sucrose gradient centrifugation method. IgM antibodies were found to persist for 4 to 5 weeks after the onset of disease, with only moderate variation being observed with respect to the different patients and the method of investigation being studied. The persistence of IgA antibodies (as examined by the fluorescent antibody technique) varied from a few weeks to several years after the onset of the disease. The detection of IgA antibodies cannot be considered as conclusive for the diagnosis of recent rubella infections.

Adolescent↗
PubMed1975

Structural studies of the Xenopus 19S immunoglobulin and 7S immunoglobulin and two immunoglobulin-like proteins.

Xenopus laevis 19S and 7S immunoglobulins (Ig) were extensively reduced and alkylated, their H and L chains spearated and their molecular weights determined. Two kinds of L chains of molecular weight 25,000 and 27,000 were revealed by SDS-polyacrylamide gel electrophoresis. In addition two Ig-like proteins consisting of heavy chains only, of 19S H-type and with similar molecular weight, were detected in Xenopus serum ans isolated. These proteins share common antigenic determinants with Xenopus 19S Ig heavy chains and are devoid of light chain determinants.

Alkylation↗
PubMed1991

Immunoglobulin subclasses and prophylactic use of immunoglobulin in immunoglobulin G subclass deficiency.

Persistent low serum levels of one or several immunoglobulin G (IgG) subclasses can be found in a high proportion of adult patients with increased susceptibility to infections. It is hard to envision that the low subclass level in itself is responsible for this susceptibility because healthy blood donors have been described who are completely devoid of certain subclasses in serum. This apparent discrepancy may be partly explained by the observation that most subclass-deficient patients have underlying aberrations in T-cell and B-cell interaction and function that may impair their capacity to compensate for even minor deficiencies. A prospective blind crossover study of the effect of prophylactic Ig substitution therapy was done in 43 adult patients with IgG subclass deficiency. The patients were randomized to receive 1 year of therapy with intramuscular Ig 25 mg/kg/wk or 1 year of saline injections. A significant protective effect of the prophylactic Ig therapy was seen with a great reduction in the number of days of infection. In addition, several immunologic parameters were altered after 1 year of Ig therapy. Nineteen of the patients later were included in an open study using 50 mg/kg/wk of Ig. After 6 months of treatment, significant protection against infection was observed, with a reduction of 6.2 days in the number of days per month with infection. This marked effect of prophylactic Ig suggests that the Ig aberrations seen in IgG subclass-deficient patients contributed to their susceptibility to infection. The effect of 25 mg/kg/wk was much less pronounced than that of 50 mg/kg/wk, and normal serum IgG subclass levels were not achieved even during the higher-dose therapy. However, it seems likely that subcutaneous or intravenous administration of larger doses of Ig would allow for more efficient therapy.

Adult↗
PubMed1986

Differential binding of immunoglobulin A and immunoglobulin G1 immune complexes to primate erythrocytes in vivo. Immunoglobulin A immune complexes bind less well to erythrocytes and are preferentially deposited in glomeruli.

Primate erythrocytes appear to play a role in the clearance of potentially pathogenic immune complexes (IC) from the circulation. This study was undertaken to compare the clearance from the circulation and tissue uptake of two monoclonal IC probes: one of which, IgG1-IC, was bound well by erythrocytes, the other of which, IgA-IC, was bound relatively poorly by erythrocytes. The IC probes were labeled with different iodine isotopes and infused either concomitantly or sequentially into the arterial circulation. The results indicate that, compared with IgG1-IC, IgA-IC bind less well to primate erythrocytes, are cleared from the circulation more quickly despite their smaller size, and show increased uptake in kidney and lung but decreased uptake in liver and spleen. Evidence is presented which suggests that this pattern of clearance from the circulation and systemic uptake of IgA-IC is the result of decreased binding of IgA-IC to circulating erythrocytes. These findings support the hypothesis that the primate erythrocyte-IC clearing mechanism may be critically important for the safe removal of IC from the circulation.

Animals↗
PubMed1967

Phylogeny of immunoglobulin structure and function. I. Immunoglobulins of the lemon shark.

Lemon sharks immunized with bovine serum albumin produced two molecular forms of antibodies detectable by passive hemagglutination of antigen-coated, tanned sheep erythrocytes. Throughout the course of immunization 2-ME-sensitive antibody was associated with a 19S immunoglobulin fraction (4-5 mg/ml serum) while late in the course of immunization antibody was found also associated with a 7S immunoglobulin fraction (7-8 mg/ml serum). No evidence for any anamnestic response was found in these animals. Naturally occurring hemagglutinins for sheep erythrocytes were found to be 2-ME-sensitive and present in the 19S immunoglobulin fraction. These immunoglobulin fractions were readily purified by DEAE-cellulose chromatography and Sephadex G-200 gel filtration. Both immunoglobulin molecules yielded equimolar amounts of H and L polypeptide chains when subjected to extensive reduction and alkylation followed by gel filtration in 5 M guanidine-HCl. Antigenically reactive H and L chains were obtained by partial reduction and alkylation followed by gel filtration in 1 M propionic acid. The 7S and 19S immunoglobulin H chains were indistinguishable by fingerprints of tryptic digests, disc electrophoretic patterns, antigenic properties, and mass (molecular weight approximately 70,000), thus suggesting these two molecules to belong to the same immunoglobulin class. The shark 19S and 7S immunoglobulin L chains were indistinguishable from each other by similar criteria and were different from the H chains. These L chains exhibited the electrophoretic heterogeneity of their mammalian counterparts. The 7S (shark immunoglobulin) molecule was shown to have a molecular weight of approximately 160,000 and to consist of 2H and 2L polypeptide chains (total mass congruent with180,000). The 19S molecule was shown to have a molecular weight of 800,000-900,000; therefore, there were probably five 7S subunits per 19S molecule, comparable to mammalian gammaM. Other reasons for considering the 7S and the 19S lemon shark molecules to belong to a class of immunoglobulins comparable to the gammaM class of mammals are that they both have high carbohydrate contents, and H chains of mass similar to micro chains. The lemon shark serum proteins with electrophoretic mobilities comparable to gamma G of mammals were not related to the immunoglobulins of this species. These proteins had no antibody activity and had no antigenic or chemical similarity to either the H chains, the L chains, or the intact immunoglobulin molecules from the lemon shark.

Animals↗
PubMed1986

Sandwich electroimmunofixation (SEIF) for the assessment of isoenzyme specificities of immunoglobulins isolated from enzyme-immunoglobulin complexes.

Sandwich electroimmunofixation (SEIF) was used to determine immunologic specificity for isoenzymes of immunoglobulins isolated from enzyme-immunoglobulin complexes. After electrophoretic separation of isoenzymes, isoenzyme-specific human immunoglobulins obtained from complexes and antihuman immunoglobulin antibodies were applied to the supporting medium and allowed to react. Complexes of isoenzyme-immunoglobulins-anti-immunoglobulin antibodies formed immunoprecipitates and were fixed in the supporting medium. After washout of the unreacted enzymes and proteins with buffer, the immunoprecipitates were stained. A comparison with control enzymograms allowed for a determination as to whether the immunoglobulins reacted with specific isoenzymes. When an immunologic reaction with more than 2 isoenzymes occurred, the specificity was quantitated by densitometry. SEIF, used to examine immunoglobulins isolated from aspartate aminotransferase-, lactate dehydrogenase-, alkaline phosphatase- and amylase-immunoglobulin complexes, was found to be a rapid and reliable technique. This approach showed that immunoglobulins differ in their specificities for various isoenzymes.

Alkaline Phosphatase↗
PubMed1989

Immunoglobulin lambda light-chain-related genes 14.1 and 16.1 are expressed in pre-B cells and may encode the human immunoglobulin omega light-chain protein.

Human pre-B cells, which produce immunoglobulin heavy chain but do not produce immunoglobulin light chain, are shown to contain a 1-kilobase transcript homologous to immunoglobulin lambda light-chain genes. Detailed analysis of RNA and cDNA clones derived from these transcripts reveals that they originate from the distinct immunoglobulin lambda-like genes 14.1/16.1. Sequence analysis of these clones reveals a long open reading frame, beginning with an ATG, capable of encoding a protein of 214 amino acids with an unprocessed molecular weight of 22,944. The C-terminal half of this predicted protein is highly homologous to immunoglobulin lambda light-chain joining and constant region protein sequence, while the amino-terminal end does not share homology with variable regions. Unlike immunoglobulin genes, these genes do not undergo rearrangement prior to expression. Analysis of a panel of 26 hematopoietic cell lines reveals that expression of 14.1/16.1 is limited to pre-B cells and one B-cell line, which, like the pre-B cells, is surface immunoglobulin negative. Antisera raised against a peptide whose sequence was predicted from the 14.1 cDNA sequence identifies a 22-kDa protein in human pre-B cells. Immunoprecipitation of immunoglobulin mu-chain from these pre-B cells with anti-immunoglobulin mu antibody coprecipitates a 22-kDa protein, which is a candidate for the human immunoglobulin omega light-chain protein and may be the protein product of the 14.1/16.1 genes.

Amino Acid Sequence↗
PubMed1976

Distributions of immunoglobulin-containing cells in alimentary tract, spleen, and mesenteric lymph node of the pig demonstrated by peroxidase-conjugated antiserums to porcine immunoglobulins G, A, and M.

Peroxidase-conjugated antibody to porcine immunoglobulins A, G, and M were used in a light microscope study of the distribution of immunoglobulins and immunoglobulin-containing cells in alimentary tract, spleen, and mesenteric lymph node of the pig. Largest populations of plasma cells staining for each of the 3 immunoglobulin classes were demonstrated in the lamina propria of the intestinal tract. Immunoglobulin A cells were most numerous, and immunoglobulin A and M cells each outnumbered immunoglobulin G cells which were, however, present in considerable numbers. Both immunoglobulins A and M were demonstrated in intestinal crypt epithelial cells, indicating they have similar intracellular secretion pathways. Porcine spleen and mesenteric lymph node seem to have a minor role in immunoglobulin synthesis.

Animals↗
PubMed1975

Anti-immunoglobulin analysis by diffusion patterns of inhibition and facilitation of complementary lysis in agar. II. Diffusion-lysis as a method for recognizing in vivo immunosuppressive activity of anti-immunoglobulins.

This paper provides evidence that it is possible to prepare facilitating anti-mouse immunoglobulin (that is, anti-mouse immunoglobulin which facilitates complementary lysis of red cells sensitized with mouse-produced haemolysin) which, when injected into mice 24 hours before an injection of sheep red cells, very markedly reduced the number of haemolysin-producing cells detectable in spleen four days later. The diffusion-lysis method was used to recognize this and other anti-Ig's in heterologous antiserum and fractions thereof. The effective antibody was in the gamma2 fraction of antiserum produced in guinea pigs by injecting them with guinea pig red cells sensitized with mouse-produced haemolysin. This method of immunizing was used in order to stimulate the production of antibody against immunoglobulin which had undergone the configurational change characteristically occurring when antibody unites with antigen. The 19S fraction of the antiserum contained inhibiting anti-mouse immunoglobulin (anti-mouse immunoglobulin which inhibits complementary lysis of red cells sensitized with mouse-produced haemolysin) and interfered with immune depression by the gamma2 fraction. It is postulated that the gamma2 fraction induces complementary lysis only of lymphocytes whose surface immunoglobulin receptors have bound antigen and undergone configurational change. It is suggested that facilitating anti-immunoglobulin of the type described is responsible for immune suppression by anti-lymphocyte serum (ALS). Facilitating anti-mouse immunoglobulin was demonstrated in two samples of ALS (anti-mouse) which were active in suppressing graft rejection, but inhibiting anti-mouse immunoglobulin only was found in a sample which was ineffective in suppressing graft rejection.

Agar↗
PubMed1990

Cells and mediators which participate in immunoglobulin synthesis by human mononuclear cells. II. The mechanism of null cell participation in immunoglobulin synthesis and secretion by B cells.

Immunoglobulins were synthesized and secreted by human B cells cultured with T cells with receptors for FcM (TM) helper cells, monocytes, null cells and PWM for 7 days. Immunoglobulin synthesis did not take place if the null cells were omitted from the cultures irrespective of the duration of the culture period. Null cells incorporated into the cultures at only 25% of their optimal concentration did not affect immunoglobulin synthesis markedly by the cultured B cells. However, the number of B cells in the culture could not be diluted without an accompanying marked reduction in immunoglobulin synthesis. The B cells synthesized and secreted significant quantities of immunoglobulin even when the null cells were added as late as day 6 of the 7-day culture whereas no or very little immunoglobulin was synthesized if the B cells were not present from the beginning of the 7-day culture. It was demonstrated that cultured null cells do not transform into B cells and do not attain their immunoglobulin-synthesizing function. Furthermore, cultured B cells do not transform into null cells and do not attain their helper function. The null cells can also be distinguished from the B cells on the basis of cell-surface markers, receptors, and blastogenic responsiveness to phytomitogens. It is concluded that (i) the human circulating B cells require the null cells, in addition to the TM cells, monocytes and PWM, in culture in order to synthesize and secrete immunoglobulin; (ii) the null cell signal that stimulates immunoglobulin synthesis and secretion by the B cells is probably the last signal following the TM helper cell, monocyte and PWM signals received by the B cells; and (iii) the null cells and the B cells constitute distinct lineages of cells.

B-Lymphocytes↗
PubMed1989

Inhibition of thyrotropin-stimulated adenylate cyclase activation and growth of rat thyroid cells, FRTL-5, by immunoglobulin G from patients with primary myxedema: comparison with activities of thyrotropin-binding inhibitor immunoglobulins.

We studied the blocking type TSH receptor antibodies in 28 patients with primary myxedema and 21 patients with goitrous Hashimoto's thyroiditis by measuring the ability of their IgGs to inhibit TSH binding to its receptor, and to inhibit TSH-stimulated cAMP increase and [3H]thymidine incorporation in a rat thyroid cell line, FRTL-5. The incidences of TSH binding inhibitor immunoglobulin, thyroid stimulation inhibiting immunoglobulin and thyroid growth inhibiting immunoglobulin in patients with primary myxedema were 54.6, 75 and 65.2%, respectively, against 14.3, 0 and 17.7%, respectively, in goitrous Hashimoto's thyroiditis. The antibodies inhibited dose-dependently not only TSH stimulated but also Graves' IgG-stimulated cAMP increase and [3H]thymidine incorporation. The TSH binding inhibitor immunoglobulin activities in patients with primary myxedema were significantly correlated with both the thyroid stimulation inhibiting immunoglobulin (r = 0.665; P less than 0.01) and the thyroid growth inhibiting immunoglobulin (r = 0.618; P less than 0.01) activity. Thirteen patients whose TSH binding inhibitor immunoglobulin activities were more than 50% had both strong thyroid stimulation inhibiting immunoglobulin (75.1-100%) and thyroid growth inhibiting immunoglobulin (57.4-100%) activities. These data suggest that the vast majority of patients with primary myxedema have potent blocking type TSH receptor antibodies. These might play a role in primary myxedema causing hypothyroidism and thyroid atrophy through inhibiting TSH-stimulated cAMP generation.

Adenylyl Cyclases↗