Transmission of human immunodeficiency virus (HIV) in North America and Europe occurs most commonly through the rectal mucosa during homosexual intercourse. The simian immunodeficiency virus (SIV) macaque model has been used to investigate rectal immunization. The vaccine used was a recombinant SIV gag p27 expressed as hybrid Ty virus-like particles (Ty-VLP). Sequential ororectal (OR) mucosal i...

We report an 11 year old boy with IgA nephropathy developing chronic myeloid leukemia on follow-up. This association suggests that a B cell defect might be involved in the pathogenesis of these two conditions.

The fact that IgA comprises the body's major isotype of antibody on a biosynthetic basis is not widely appreciated because IgG, not IgA, is the predominant isotype in serum. Nevertheless, the bulk of the body's Ig-producing cells reside in the various mucosal and exocrine sites, especially along the intestinal tract, and most of them make IgA anti-bodies against environmental antigens, includin...

The live-attenuated influenza vaccine (LAIV) has generally been more efficacious than the inactivated vaccine in children. However, LAIV is not recommended for HIV-infected children because of insufficient data. We compared cellular, humoral, and mucosal immune responses to the 2013-2014 LAIV quadrivalent (LAIV4) in HIV-infected and uninfected children 2-25 years of age (yoa). We analyzed the r...

The intestine is undoubtedly the most misunderstood and under-appreciated lymphoid organ in the body. Yet, in the eyes of mucosal immunologists, the gut exemplifies finely tuned, extensively interacting populations of cells and their products involved in innate and specific defence of the body’s largest surface area, a surface exposed to the heaviest burden of environmental antigens. As the lar...

In mammals, VDJ recombination is responsible for the establishment of a highly diversified preimmune antibody repertoire. Acquisition of a functional Ig heavy (H) chain variable (V) gene rearrangement is thought to prevent further recombination at the IgH locus. Here, we describe VHQ52(NT); Vκgr32(NT) Ig monoclonal mice reprogrammed from the nucleus of an intestinal IgA(+) plasma cell. In VHQ52...

Abstract Peyer’s patches (PPs) are the major site for T-cell dependent IgA B-cell differentiation. Segmented filamentous bacteria (SFB) commensal that preferentially colonize ileum, mainly over PPs. SFB colonization of germ-free mice induces polyclonal responses by unclear mechanisms. Using scmRNAseq and flow cytometry we found SPF induced an increase in size overall cell number PPs includes en...

The mechanism of the hypogammaglobulinemia in patients with chronic lymphocytic leukemia (CLL) was studied by determining the generation of specific immunoglobulin-secreting cells in response to mitogen and antigen stimulation in culture. Normal peripheral blood B lymphocytes from 18 normal subjects cocultured with equal numbers of autologous T cells generated cells secreting 2,542 +/- 695 IgG,...

Although mechanisms operative in the induction and maintenance of specific, adaptive immunity, including 'cognate' B/T interactions, have been extensively studied and defined, we still know little about the mechanisms operative in developing and maintaining B- and T-cell dependent 'natural' immunity. Particularly, we are still rather ignorant concerning gut microbial/gut or systemic APC, T cell...

Multiple sclerosis (MS) is characterised by intrathecal synthesis of IgG, less frequently of IgA and IgM. Local production of antibodies to myelin basic protein (MBP) and other myelin components has also been reported, and autoimmune pathogenesis has been postulated. Whether MS is accompanied by a systemic B cell response is less clear. To elucidate this question, we examined bone marrow and pe...