Antineoplastic effect of bacterial superantigens in a model of human acute T-lymphoblastic leukemia

ALEJANDRA DUARTE; MONTAGNA, DANIELA R.; PASTORINI MERCEDES; RUGGIERO RAUL; ALEMAN MECEDES

Mar del PLata

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2022

SAIC

Bacterial Superantigens (SAgs) are bacterial proteins that bind to major histocompatibility complex (MHC) class II molecules as unprocessed proteins and subsequently interact with a large number of T cells expressing certain Vβ chains in TCR, triggering T cell apoptosis. We have previously shown that SAgs could specifically induce apoptosis of neoplastic T cells in mice and could even increase the survival of mice bearing T-cell lymphomas. Here we investigated the effect of SAgs SEE (enterotoxin E from the bacterium Staphylococcus aureus), which specifically interacts with cells expressing the Vβ8 chain, on the human neoplastic cell line Jurkat, which carries the Vβ8 chain of the TCR. Preliminary experiments showed that SEE SAg was capable of inducing apoptosis of Jurkat cells by significantly reducing the tumor size and blood infiltration of neoplastic cells in NOD/Scid mice model. In the present work we confirm these results and we evaluated whether SAgs were capable of improving the survival of mice carrying human neoplastic T cells. Jurkat cells (10x106) were inoculated intravenously (i.v.) and after two days the mice were treated with SAg or PBS, monitoring weight and behavior every 7 days. SAgs-treated mice did not lose weight compared to untreated mice (SEE vs PBS *p