Tucaresol down-modulation of MUC1-stimulated human mononuclear cells

Abstract

Interaction between antigen presenting cells and T lymphocytes, through receptors and co-stimulatory molecules present on the surface of these cells, is one of the key means to modulate the adaptive immune system. Tucaresol, a Schiff-base-forming chemical, can be used as a substitute for the physiological donor of carbonyl groups of antigen presenting cells, which can interact with the amine groups of T lymphocytes to modulate the adaptive immune system. This study was done to determine whether tucaresol can enhance killing of cancer cells in vitro as well as protect non-obese diabetic severe combined immunodeficient mice from tumor development by mucin 1 stimulated human mononuclear cells through the adaptive immune system. The expected hypothesis was not supported. Percent specific lysis of MCF-7 tumor cells by mucin 1 stimulated human mononuclear cells was reduced by tucaresol. Furthermore, tucaresol abolished the protective effect of mucin 1 stimulated human mononuclear cells against MCF-7 breast cancer cell growth in non-obese diabetic severe combined immunodeficient mice. This study implies that tucaresol may be of use as an immunosuppressive agent.

• Immunosuppression
• T lymphocytes
• tucaresol

Acknowledgements

The authors are grateful to the Coffee Memorial Blood Center, Amarillo, TX and the Harrington Cancer Center, Amarillo, TX, for PBMC, and to those mentioned in the text for materials and/or services. Jody D. Piper participated in the initial phase of the studies. We thank Shahriar Absar for power analysis.