Abstract 1653: Toward developing a humanized mouse model of the microenvironment associated with the malignant cells of Hodgkin lymphoma

Abstract

Abstract The tumor microenvironment (TME) represents a highly complex compartment that includes cancer cells, non-hematopoietic stromal cells, extracellular matrix, lymphocytes, and myeloid cells. Interactions between these populations and the factors they secrete play critical roles in determining the host response to cancer. Conventional mouse xenograft models of human cancer lack a competent immune system. Indeed, the use of xenograft models often fail to translate into effective human treatments. Classical Hodgkin Lymphoma (HL) is characterized by the presence in the lymphonodes of abnormal Reed-Sternberg cells, and many cell types beyond them, in particular Treg. To reconstitute a more complete TME, human PBMCs were injected into NSG mice bearing L540 HL cells. Then over time the presence of various human CD45+ cell populations were monitored within the tumor mass, in the spleen and in circulation. The goal of our study is to gain a better understanding of the interaction of the immune cell infiltrates into the HL microenvironment, leading ultimately to improved treatment outcomes. Lymphocyte infiltration into the tumor showed a predominance of human CD3+ cells (T lymphocytes), even if in the spleen we found both human T and B cells, indicating that this model might help us design more effective treatments. To reflect the immune reconstitution of these animals and its interaction with tumor and to better understand the capacity of T lymphocytes to kill the cancer cells, we evaluated the production of human IFN- gamma. We found an increase of IFN- gamma in L540-bearing mice reconstituted with hPBMCs compared to the mice without them, indicating a certain functionality of the T cells in these tumors. Moreover, in this model, the immune reconstitution did not decrease tumor growth, rendering this model useful for the study of biotherapeutic and immunotherapeutic studies. The model might be useful to study the anticancer therapy at a preclinical level because a remodeling of the anti-tumor immune response can be evaluated. Citation Format: Maria Teresa Bilotta, Antonella Antignani, David J. Fitzgerald. Toward developing a humanized mouse model of the microenvironment associated with the malignant cells of Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1653.