Induction of protein tyrosine phosphorylation in macrophages incubated with tumor cells.
The cellular and molecular interaction between monocyte/macrophage and tumor cells leading to macrophage activation is not clearly understood. Since protein tyrosine phosphorylation appears to be a major intracellular signalling event, we checked whether the tumor cells alter tyrosine phosphorylation of proteins in macrophages. We found that both L929 and Yac-1 tumor cells induced increased tyrosine phosphorylation of several polypeptides in peritoneal as well as P388D-1 and IC-21 macrophages. Macrophages co-cultured with tumor cells also showed increased fluorescence with anti-phosphotyrosine-FITC antibody. These observations suggest that increased tyrosine phosphorylation plays a role in tumor cell-induced activation of macrophages.
Sodhi
A
A
School of Biotechnology, Banaras Hindu University, Varanasi, India.
Shrivastava
A
A
Kumar
R
R
D000818:Animals; D002460:Cell Line; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D008262:Macrophage Activation; D008264:Macrophages / Q000201:enzymology*; D017737:Macrophages, Peritoneal / Q000201:enzymology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009374:Neoplasms, Experimental / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism
D010750:Phosphoproteins; D019000:Phosphotyrosine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases