DELAYED ASSESSMENT OF IMMUNOLOGICAL FUNCTION ALLOWING FOR TRANSPORTATION OF LYMPHOID TISSUES TO DISTANT LABORATORY SITES

Abstract

The immune system is a frequent target for chemical toxicity. Accordingly, a number of immunotoxicological assays are performed during the research and development of new chemical products. One of the most sensitive and commonly used immunoassays is the Hemolytic Antibody-Forming Cell assay (AFC). Although the exposure of laboratory animals tochemicals and the subsequent immunotoxicological evaluation of lymphoid organs are typically conducted at the same research facility, there are instances in which laboratories have either limited assay expertise or limited exposure capabilities. Studies were conducted to ascertain the feasibility of performing the AFC assay up to 24 h following spleen removal, thereby allowing tissue transportation to a distant laboratory for evaluation. Female B6C3F1 mice and Fischer 344 rats were sensitized intravenously with sheep red blood cells. Four days later spleens were aseptically removed and stored at 4 C for up to 24 h until assessed in the AFC assay. Splenocyte viability and IgM AFC/106 splenocytes from both murine and rat spleens kept overnight compared favorably totheAFC responseproduced from splenocytes analyzed immediately after sacrifice. Furthermore, both single-cell suspensions and spleen halves maintained good viability and resulted in statistically equivalent AFC responses in comparison to splenocytes from 0-h control rats and mice. These studies suggest that intact spleens from female B6C3F1 mice and Fischer 344 rats can be transported and assessed in an AFC assay up to 24 h following organ collection. Furthermore, the longevity of single-cell suspensions and spleen halves allows multiple endpoints to be assessed in different facilities using the same research animals; this approach provides the additional advantage of reducing the total number of animals necessary when evaluating the safety of a given chemical or drug.

Keywords: :

• Antibody Forming Cell Assay;Sheep Red Blood Cells;B6c3f1 Mice;F344 Rats;In Vivo