Indirect Leukocyte Migration Inhibition in Breast Cancer and Benign Breast Disease Patients by Mouse Mammary Tumor Virus Grown in Feline Kidney Cells

Indirect migration inhibition assays were performed with normal and mammary tumor-bearing C3H/HeN mice and patients with breast disease to assess cellular immunity against three different mouse mammary tumor virus (MTV) preparations grown in feline kidney cell cultures and against a mouse-derived MTV preparation. MTV obtained after passage through feline kidney cells and the mouse-derived MTV were capable of eliciting macrophage migration inhibitory factor production by mouse spleen cells obtained from normal or mammary tumor-bearing C3H/HeN mice, thus demonstrating a similar degree of antigenicity of these preparations. In experiments with human breast cancer patients' leukocytes, leukocyte inhibitory factor (LIF) was produced by 32–50% of these patients in response to the mouse-derived MTV or to three different MTV preparations obtained after passage through feline kidney cells. A significant proportion (31–54%) of benign breast disease patients also reacted with both the mouse-derived and feline-derived MTV preparations. Patients with both malignant and benign breast disease, however, had a significantly different (P