BREAST-CANCER AND T-CELL-MEDIATED IMMUNITY TO PROTEINS OF THE MOUSE MAMMARY-TUMOR VIRUS (MMTV)

We have previously reported that breast cancer patients and some healt hy subjects show positive T-cell-mediated immune responses to a semi-p urified mouse mammary tumour viral pool (MMTV). We have now used Weste rn blotting to analyse the specificity of the response and to determin e the target polypeptides. Two types of T-cell response to the viral a ntigens were examined, proliferation and MIF release, the latter impli es a DTH status in vivo where primed lymphocytes are involved. Two vir al fractions were used, one containing a glycoprotein, the 52 kD major virus envelope , and the other containing the 28 kD main virus core p rotein. We analysed both patients and healthy subjects whose T-cells p roliferated to the MMTV total extract (viral pool). The T-cell respons e in the patients was shown to be viral specific since both the T-cell proliferation (21/25) and MIF release (17/19) were directed against v iral components of the pool (gp 52 and/or p 28). The T-cell response i n the healthy control subjects was shown to be mostly directed against a species-specific albumin component of the extract. In addition, the monocyte integrity required for the MIF response was altered in the b reast cancer patients. The monocytes from one patient out of three rai led to respond to MIF, even though the lymphokine was released normall y by the patients' activated T-cells.