Affinity maturation of B lymphocytes is a process that includes somatic hypermutation and class switch recombination. Class switch recombination is a fundamental factor of the human adaptive immunity. The perturbation of this process has an adverse effect on human health, and results in global chromosome rearrangements and cell transformation. Evaluation of the class switch recombination efficiency is an important component of laboratory diagnosis of immunotoxic components. Here we describe a method for testing the efficiency of the class switch recombination. Cultivation of mouse myeloma CH12F3-2 cell line with anti-CD40 antibodies, transforming growth factor beta, and recombinant interleukin-4 (IL-4) triggers a cascade of signal transduction network events that lead to switching the immunoglobulin isotypes from IgM to IgA. This chapter describes the methodology of class switch recombination assay for assessment of the effect of environmental pollutants in toxicological laboratory diagnostics.
Keywords: Cadmium toxicity; Class switch recombination; Flow cytometry; Interleukin-4; NF-κB signaling; Real-time PCR; SMAD signaling; STAT6 signaling.