Exploring Pesticide Effects On Hematopoiesis and the Thymus

Hematopoiesis in the bone marrow (BM) produces red blood cells, platelets, or various white blood cells. Common lymphocyte progenitors in the BM can migrate to the thymus to form T lymphocytes, a type of immune cell. In some cases, bone marrow failure (BMF) arises from impairments in hematopoiesis and results in the inability to produce necessary blood cells. California’s Central Valley has a high exposure to pesticides due to agriculture. Past research shows correlations between leukemia and high pesticide exposure, but surprisingly, there has been little published research regarding the direct effects of pesticides on BMF. This study aims to use mouse models to aid our understanding of the molecular effects of two pesticides, abamectin and pyraclostrobin, on hematopoiesis. In previous studies, abamectin led to weight loss while pyraclostrobin led to weight gain. We hypothesize that changes in the BM due to pesticide exposure may result in lower numbers of T lymphocytes. We exposed 8-week-old C57BL/6 mice to pyraclostrobin or abamectin for 14 days via intraperitoneal injections and monitored their health with routine weighing and complete blood cell analysis using a Hemavetcell counter. After 14 days, we collected BM and spleen cells for flow cytometric analysis on a ZE5 Cell Analyzer and the thymus for histology. We expect to see a decrease in T lymphocytesin the periphery and impairments in the thymus structure.