We review how polyreactive natural IgM autoantibodies (IgM-NAA) protect the host from invading micro-organisms and host neo-antigens that are constantly being produced by oxidation mechanisms and cell apoptosis. Second, we discuss how IgM-NAA and IgM anti-leukocyte antibodies (IgM-ALA) inhibits autoimmune inflammation by anti-idiotypic mechanisms, enhancing removal of apoptotic cells, masking n...

In prior studies, we show that naturally occurring IgM anti-leukocyte autoantibodies (IgM-ALA) bind to CD3, CD4, CCR5, and CXCR4 receptors. These observations prompted us to determine whether IgM-ALA have a role in inhibiting HIV-1 infectivity by inhibiting viral entry into cells. We show that purified IgM, but not IgG, from individual sera of both normal and HIV-1 infected individuals is highl...

Normal mouse IgM is synthesized as hexamers in the absence of J chain and as pentamers in its presence. Previous work has suggested that polymer size is also closely related to formation of the inter-mu chain disulfide bond mediated by cysteine 414, one of three cysteines involved in inter-mu chain bonding. This correlation in turn suggested that formation of C414-C414 might be required for J c...

Hantaan virus is the causative agent of severe hemorrhagic fever with renal syndrome. Clinical surveillance for Hantaan virus infection is unreliable, and laboratory verification is essential. The detection of virus-specific immunoglobulin M (IgM) and IgG in serum is most commonly used for the diagnosis of hantavirus infection. Testing of oral fluid samples instead of serum offers many advantag...

Eighty-seven serum specimens from 20 human subjects experimentally inoculated one or more times with Norwalk virus were quantitatively examined for virus-specific immunoglobulin M (IgM). A sensitive and specific radioimmunoassay for anti-Norwalk virus blocking activity was applied to whole serum and to separate IgM and IgG fractions obtained by sucrose density gradient ultracentrifugation. The ...

The trapping of IgM-containing immune complexes (ICs) by follicular dendritic cells (FDCs) serves as an important step in promoting germinal center (GC) formation. Thus, the deposition of IgM-containing ICs on FDCs can be detected by antibodies recognizing IgM. The present investigation provides the first comprehensive report on the IgM staining pattern in follicular lymphoma (FL, n = 60), with...

It is well known that B-1 B cells are the main cell type that is responsible for the production of natural immunoglobulin M (IgM) and can respond to infection by increasing IgM secretion. However, we unexpectedly found that some epithelial cells also can express rearranged IgM transcript that has natural IgM characteristics, such as germline-encoded and restricted rearrangement patterns. Here w...

The Ly$\alpha$ luminosity function (LF) of emitters (LAEs) has been used to constrain the neutral hydrogen fraction in intergalactic medium (IGM) and thus timeline cosmic reionization. Here we present results a new narrow-band imaging survey for $z=7.3$ LAEs large area $\sim 3\ \mathrm{deg}^2$ with Subaru/Hyper Suprime-Cam. No are detected down $L_{\mathrm{Ly}\alpha}\simeq 10^{43.2}\ \mathrm{er...