Figure 2.

Membrane-bound immune-modulators are bioactive on the surface of MDCK CYT-IVAC producer cells. Mitomycin C treated subclones (SC) or FACS sorted (sort) CYT-IVAC producer cells expressing murine GM-CSF (A), IL-2 (B), or IL-4 (C) or wild-type MDCK cells were co-cultured with cytokine specific indicator cells, bone marrow (BM), CTTL-2 and CT.4s respectively. Proliferation of cytokine responsive cell lines was measured by ³H-thymidine incorporation. Recombinant protein was used as positive control.