Studies on the bone marrow colony stimulating factor (CSF): Relation of tissue CSF to serum CSF

Fluctuations in the colony stimulating factor (CSF) content of submaxillary salivary gland, lung, kidney and spleen were studied in male C 57 BL mice which had been subjected to a variety of stimuli (endotoxin, x‐irradiation or polyadenylic‐polyuridylic acid complex) that caused elevations of the serum CSF. The temporal relationships and magnitudes of the rises in CSF were complex and differed from tissue to tissue according to the stimulus used. In the tissues examined not only was the measurable CSF content in each case found to equal or exceed the prestimulatory levels, but in some cases distinctly different forms of CSF were observed as shown by differences in the zone sedimentation, electrophoretic, and calcium phosphate binding characteristics of the material. The patterns of response to the stimuli investigated suggested that tissue injury either directly, or indirectly via the release of various cellular constituents, might mediate the release of CSF by various widely disseminated and/or differing cell types.