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Papers by Art Wittwer
Journal of Cellular Physiology, 1993
Rat cytokine-induced neutrophil chemoattractant (CINC) is an eight kilodalton polypeptide origina... more Rat cytokine-induced neutrophil chemoattractant (CINC) is an eight kilodalton polypeptide originally purified from media conditioned by interleukin-1 p stimulated 52E, an epitheloid clone derived from normal rat kidney (NRK) cells. Using a fibroblastic clone of the NRK cells, 49F, we found expression of the ClNC gene to be induced by either serum or cytokines in growth-arrested cultures within 1 hour of stimulation. There was no observable ClNC expression in exponentially growing cells in the absence of cytokine stimulation. ClNC protein had no significant effect on 'H-thymidine incorporation or growth rate of NRK49F. We have observed that ClNC is constitutively produced by some transformed NRK cells, clone RC20, suggesting an association with the expression of a transformed phenotype. Unlike the parent 49F, RC20 cells are capable of growth in soft agar and serumfree media and form highly metastatic tumors in nude mice. We have examined the possible autocrine functions of ClNC and its possible links to the expression of the transformed phenotype by these cells. The use of a blocking ClNC polyclonal antibody demonstrated that ClNC did not function as an autocrine growth factor for RC20. Though ClNC is a potent chernoattractant for neutrophils, it did not induce migration of either RC20 or 49F cells. ClNC only moderately promoted adhesion of KC20 cells when used as a matrix protein. These data do not support the hypothesis that production of ClNC by the RC20 cells provides an obvious advantage for the transformed cells constitutively producing it.
Journal of Cellular Physiology, 1993
Rat cytokine-induced neutrophil chemoattractant (CINC) is an eight kilodalton polypeptide origina... more Rat cytokine-induced neutrophil chemoattractant (CINC) is an eight kilodalton polypeptide originally purified from media conditioned by interleukin-1 p stimulated 52E, an epitheloid clone derived from normal rat kidney (NRK) cells. Using a fibroblastic clone of the NRK cells, 49F, we found expression of the ClNC gene to be induced by either serum or cytokines in growth-arrested cultures within 1 hour of stimulation. There was no observable ClNC expression in exponentially growing cells in the absence of cytokine stimulation. ClNC protein had no significant effect on 'H-thymidine incorporation or growth rate of NRK49F. We have observed that ClNC is constitutively produced by some transformed NRK cells, clone RC20, suggesting an association with the expression of a transformed phenotype. Unlike the parent 49F, RC20 cells are capable of growth in soft agar and serumfree media and form highly metastatic tumors in nude mice. We have examined the possible autocrine functions of ClNC and its possible links to the expression of the transformed phenotype by these cells. The use of a blocking ClNC polyclonal antibody demonstrated that ClNC did not function as an autocrine growth factor for RC20. Though ClNC is a potent chernoattractant for neutrophils, it did not induce migration of either RC20 or 49F cells. ClNC only moderately promoted adhesion of KC20 cells when used as a matrix protein. These data do not support the hypothesis that production of ClNC by the RC20 cells provides an obvious advantage for the transformed cells constitutively producing it.