Selective IgM deficiency was diagnosed in a 3-month-old Standardbred colt that was referred for chronic respiratory tract disease. Immunoglobulin quantification revealed normal IgG and IgA concentrations, but undetectable IgM concentration. Stimulation of blood lymphocytes with the T-cell mitogens concanavalin A and phytohemagglutinin yielded results within the normal range. However, stimulation with the B-cell mitogen lipopolysaccharide produced no response. A B-cell defect similar to that associated with several immunodeficiency disorders in people was suggested as the cause of the IgM deficiency in this colt.
Download full-text PDF |
Source |
---|
Biomedica
December 2024
Universidad del Valle, Cali, ColombiaDepartamento de Microbiología, Facultad de Salud, Universidad del Valle, Cali, Colombia; Genetic Immunotherapy Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Disorders, National Institutes of Health, Bethesda, MD, USA.
Activated phosphoinositide 3-kinase δ syndrome is an inborn error of immunity due to mutations within the genes responsible for encoding PI3Kδ subunits. This syndrome results in an excessive activation of the phosphoinositide 3-kinase signaling pathway. Gainof-function mutations in the gene PIK3R1 (encoding p85α, p55α, and p50α) lead to the development of the activated PI3K δ syndrome.
View Article and Find Full Text PDFJ Clin Immunol
January 2025
Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, WA, USA.
Reduced function or hypomorphic variants in recombination-activating genes (RAG) 1 or 2 result in a broad clinical phenotype including common variable immunodeficiency (CVID) and even adult-onset disease. Milder RAG variants are less characterized. Here we describe the longitudinal course of a milder combined RAG deficiency in 3 of 7 siblings sharing the same RAG2 mutations over a 50-year study.
View Article and Find Full Text PDFJ Immunother Precis Oncol
February 2025
Department of Pediatrics, Division of Immunology, Allergy and Retrovirology, Baylor College of Medicine, Houston, TX, USA.
Immunoglobulins (Igs) are produced by B lymphocytes and play a key role in humoral immunity. Igs are classified into five isotypes (IgG, IgA, IgM, IgE, and IgD). Their primary function is to recognize and bind to foreign antigens.
View Article and Find Full Text PDFAllergy
January 2025
Schroeder Allergy and Immunology Research Institute, Department of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, Canada.
Allergic reactions to foods are primarily driven by allergen-binding immunoglobulin (Ig)E antibodies. IgE-expressing cells can be generated through direct switching from IgM to IgE or a sequential class switching pathway where activated B cells first switch to an intermediary isotype, most frequently IgG1, and then to IgE. It has been proposed that sequential class switch recombination is involved in augmenting the severity of allergic reactions, generating high affinity IgE, differentiation of IgE plasma cells, and in holding the memory of IgE responses.
View Article and Find Full Text PDFCytometry B Clin Cytom
January 2025
Department of Pediatrics, Section of Allergy and Immunology, University of Colorado School of Medicine, Aurora, Colorado, USA.
A reduced proportion of peripheral class-switched memory B cells (CSM-B cells) is presumed to indicate ineffective germinal activity. The extent that this finding corresponds to a plausible germinal center failure pathophysiology in patients not diagnosed with CVID or hyper IgM syndrome is not known. We asked if patients with low CSM-B cells are more likely to demonstrate failure to produce serum IgA and IgG than counterparts with nonreduced class-switched memory B cell levels, regardless of diagnosis.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!