Project ID: D2011-08
Description:
The phenotype of B cells responsible for the production of anti-pneumococcal polysaccharide antibody has been unclear. Although individuals that respond poorly to the 23-valent pneumococcal polysaccharide (PPS) vaccine, Pneumovax, are profoundly deficient or lack IgM memory cells (CD27+IgM+), they are also deficient in the switched memory (CD27+IgM2) compartment. Direct characterization of PPSspecific B cells has never been performed.
To identify pneumococcal polysaccharide (PPS) specific B cells, researchers at The University of Toledo labeled PPS14 and PPS with fluorescent markers. Fluorescently labeled PPS were used in FACSAria flow cytometry to characterize the phenotype of PPS-specific B cells obtained from 18 young adults pre- and postimmunization with Pneumovax. The labeled PPS were capable of inhibiting binding of Ab to the native PPS. Similarly, the native PPS were able to inhibit binding of PPS-specific B cells in a flow cytometric assay demonstrating specificity and functionality. This technology allows to identify the phenotype of PPS-specific B cells, which has been problematic in the past. This technology can also be applied to other bacterial, parasitic, fungal and cellular carbohydrates.
References:
Khaskhely, N; Mosakowski, J; Thompson, RS; Khuder, S; Smithson, SL; Westerink, MA. Phenotypic analysis of pneumococcal polysaccharide-specific B cells. J Immunol. 2012; 188(5):2455-63