Introduction: Cholesterol, a major ingredient of cellular growth, is maintained in the cells by either intracellular biosynthesis or LDL receptor mediated endocytosis. Various studies have shown increased LDLR and SREBP2 (transcription factor) expressions as well as intracellular saturation of cholesterol in malignant and proliferating cells.

Objectives: Citation of immune suppression is common in malignancy. B cells are antibody forming immune cells. Fate of Benzo-alpha-pyrene (mitogenic and carcinogenic doses) on B-cells has been aimed by exploring the role of cellular cholesterol homeostasis.

Methods: Intraperitoneal injection of carcinogen, classical mitogen and immunogen to Swiss Albino mice in groups for optimally effective dose, B-cell (CD19 & CD79a) counts by flowcytometry, ELISA for IgG estimation, western blot for protein expressions and spectrophotometry for cholesterol estimation were among the parameters studied.

Results: At immunosuppressive dose of Benzo-alphapyrene a significant decrease in serum IgG level, no significant change in number of B lymphocytes as compared with other agents, depressed expressions for LDLR / SREBP2 and significant decrease of cellular cholesterol (cytosolic and nuclear) were observed in mice model system.

Conclusion: Benzo-alphapyrene leads to decrease in LDLR and SREBP2 expression resulting insufficient total intracellular cholesterol level and thus affects B-cell to proliferate. Immunosupression becomes apparent, which allows carcinogen to stay in the system and generation of tumor elsewhere.

Citation Format: Nimisha Saxena, Sr., Amar Preet Kaur, Sr., Nimai Chand Chandra. Alteration in cholesterol homeostasis and antibody synthesis in B cells an in-vivo effect of carcinogen (polyaromatic). [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2016 Oct 20-23; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2017;5(3 Suppl):Abstract nr B65.