We have studied the role of secreted immunoglobulin (Ig)M in protection from infection with influenza virus and delineated the relative contributions of B-1 versus B-2 cell-derived IgM in this process. Mice deficient in secreted IgM but capable of expressing surface IgM and secreting other Ig classes show significantly reduced virus clearance and survival rates compared with wild-type controls....

Background: The study of antiphospholipid antibodies (aPL), not included in the Sydney diagnostic criteria, syndrome (APS) and systemic lupus erythematosus (SLE) is poorly understood. Objectives: To determine frequency detection IgA-aCL IgA-aβ2GP1 IgG to β2GP1 domain 1 (IgG-aβ2GP1-D1) patients with APS without SLE. Methods: ELISA chemiluminescence assays (CMA) were used test 63 sera patients: 2...

IgM antibodies specific for a certain antigen can enhance antibody responses when administered together with this antigen, a process believed to require complement activation by IgM. However, recent data show that a knock-in mouse strain, Cμ13, which only produces IgM unable to activate complement, has normal antibody responses. Moreover, the recently discovered murine IgM Fc receptor (FcµR or ...

An important role for immunoglobulin M (IgM) during early acute virulent Toxoplasma gondii infection was identified using IgM-/- mice that lack surface and secretory IgM but maintain normal B-cell functionality and isotype class switching. Following intraperitoneal inoculation with the virulent RH strain, IgM-/- mice displayed significantly fewer peritoneal parasites than wild-type (WT) mice, w...

Autoimmunity is associated with defective phagocytic clearance of apoptotic cells. IgM deficient mice exhibit an autoimmune phenotype consistent with a role for circulating IgM antibodies in apoptotic cell clearance. We have extensively characterised IgM binding to non-apoptotic and apoptotic mouse thymocytes and human Jurkat cells using flow cytometry, confocal imaging and electron microscopy....

An immunoglobulin M (IgM)-immunosorbent agglutination assay (IgM-IS-AGA) was negative in all sera from individuals negative in the Sabin-Feldman dye test, in sera from individuals with chronic Toxoplasma infection, and in cord blood samples from uninfected infants. In contrast, all sera that were obtained from individuals with a recent history of acute Toxoplasma infection and from infants with...

hyper-igm syndromes are characterized by profound reduction of serum igg, iga, and ige levels with normal or increased concentrations of serum igm. cd40 ligand deficiency is x-linked form of the disease, which results in a lack of immunoglobulin class switching from igm to igg in b cells. in addition to the recurrent infections, a number of patients suffer from neutropenia. there are some evide...

conclusions we concluded that psychiatric patients in general and schizophrenia and bipolar cases in particular had a significantly higher relative frequency of t. gondii infection than healthy individuals of lorestan province, western iran. results out of the 170 psychiatric patients, 103 (63.5%) patients were seropositive for igg antibody and 14 (8.2%) were seropositive for igm antibody. of t...

background: tonsils and adenoids are involved in both local immunity and immune surveillance for the development of immune defense mechanisms. a number of investigators have found decreased immunoglobulin levels after adenotonsillectomy while others have failed to find significant changes. the effects of adenotonsillectomy on the cellular immunity of children have not been investigated extensiv...