NOVEL ROLE OF HISTAMINE H4 RECEPTOR IN ANTITUMOR IMMUNITY

MELISA BEATRIZ NICOUD ; HELENA STERLE ; MÓNICA ALEJANDRA TÁQUEZ DELGADO ; MARÍA DE LA PAZ SARASOLA ; DANIELA LORENA SPEISKY ; KARINA FORMOSO ; AGUSTINA VIDAL ; NOELIA MASSARI ; GRACIELA CREMASCHI; VANINA ARACELI MEDINA

Mar del Plata

Congreso; REUNIÓN ANUAL DE SOCIEDADES DE BIOCIENCIA 2019; 2019

The histamine H4 receptor (H4R) is the last discovered histamine receptor subtype and is mainly expressed in cells of the immune system, showing numerous immunomodulatory roles. Its functional expression is further described in different types of tumors. The use of H4R knockout mice (H4R-KO) could contribute to better understand the pathophysiological relevance of H4R in cancer and other immunological disorders. This study aimed to explore some immune-related responses in H4R-KO in comparison to wild-type (WT) mice and to evaluate the participation of H4R in antitumor immunity in a model of breast cancer. We first evaluated the composition of immune cell subsets in spleens and lymph nodes from H4R-KO and WT Balb/c mice by flow cytometry. We further assessed growth parameters, histological characteristics and the composition of tumor, tumor draining lymph node (TDLN) and spleen immune subsets in a syngeneic model of breast cancer developed orthotopically with LM3 cells. Mice lacking H4R showed reduced CD4+/CD8+ ratio and increased percentage of NK cells in lymph nodes compared to WT mice (p