Generation of tumoricidal effector cells by human C-reactive protein and muramyl tripeptide: a comparative study.
C-reactive protein (CRP) delivered in liposomes [CRP-multilamellar vesicles (MLV)] has been demonstrated to inhibit lung and liver metastases in C57 mice bearing the syngeneic tumors T241 fibrosarcoma and MCA-38 colon carcinoma, respectively. Also peritoneal exudate cells (PEC) from CRP-MLV-treated animals exhibited tumor inhibitory activity in the Winn neutralization assay, and the magnitude of this activity was comparable to that of PEC from muramyl tripeptide (MTP)-MLV-treated mice. The present studies were carried out to compare the mechanisms involved in generation of the tumoricidal effector cell by CRP-MLV and MTP-MLV. The antitumor activity of both CRP-MLV- and MTP-MLV-activated PEC was markedly inhibited by antimacrophage antiserum and complement in the Winn neutralization assay. Also, both activities were unaffected by treatment with anti-immunoglobulin antiserum and complement. However, antitumor activity of CRP-MLV-activated PEC was inhibited by anti-Thy 1.2 and antiasialo Gm 1 antisera in the presence of complement, whereas these reagents had no effect on MTP-MLV-activated PEC. Thus, the antitumor effect of MTP-MLV appears to be mediated principally by macrophages, whereas that of CRP-MLV may also involve other cells bearing T- and/or natural killer-cell markers.
Gautam
S
S
Department of Immunopathology, Cleveland Clinic Foundation, Ohio 44195-5131.
Deodhar
S
S
D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000818:Animals; D002097:C-Reactive Protein / Q000008:administration & dosage / Q000627:therapeutic use*; D003165:Complement System Proteins / Q000627:therapeutic use; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004337:Drug Carriers; D005677:G(M1) Ganglioside; D006028:Glycosphingolipids / Q000276:immunology; D007106:Immune Sera / Q000008:administration & dosage; D007136:Immunoglobulins / Q000276:immunology; D007518:Isoantibodies / Q000276:immunology; D008081:Liposomes; D008264:Macrophages / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000188:drug therapy*; D009500:Neutralization Tests
D004337:Drug Carriers; D006028:Glycosphingolipids; D007106:Immune Sera; D007136:Immunoglobulins; D007518:Isoantibodies; D008081:Liposomes; C035678:anti-Thy antibody; D005677:G(M1) Ganglioside; D000119:Acetylmuramyl-Alanyl-Isoglutamine; C035104:muramylNAc-Ala-isoGln-Lys-tripeptide; C018835:asialo GM1 ganglioside; D003165:Complement System Proteins; D002097:C-Reactive Protein