Submandibular gland-conditioned medium enhancement of bone marrow colony-forming cells in tumor-bearing murine recipients.

Soft-agar clonogenic assay techniques were used to examine 2 sources of colony-stimulating activity (CSA), submandibular gland-conditioned medium (SMG-CM) and pregnant mouse uterine extract (PMUE), for potentiation of granulocyte-macrophage (GM-CFUc) or monocyte-macrophage (M-CFUc) progenitor cell populations. The femoral populations being examined were aspirated from normal mice and from those bearing 1 of 2 types of tumor: Lewis lung carcinoma (3LL) or thymic lymphoma ascites tumor (EL-4). When PMUE was used as a CSA source, normal animals showed a greater clonogenic response per population than either of the tumor-bearing groups. When SMG-CM was used as a CSA source, the pattern of GM-CFUc response was much different: GM-CFUc magnitudes increased by fourfold to sixfold over normal levels in tumor-bearing animals. M-CFUc response patterns were also significant, being similar in response but smaller.