title: Murine carcinoma expressing carcinoembryonic antigen-like protein is restricted by antibody against neem leaf glycoprotein.
abstract: We have generated a polyclonal antibody against a novel immunomodulator, neem leaf glycoprotein (NLGP) that can react to a specific 47 kDa subunit of NLGP. Generated anti-NLGP antibody (primarily IgG2a) was tested for its anti-tumor activity in murine carcinoma (EC, CT-26), sarcoma (S180) and melanoma (B16Mel) tumor models. Surprisingly, tumor growth restriction was only observed in CT-26 carcinoma models, without any alteration in other tumor systems. Comparative examination of antigenicity between four different tumor models revealed high expression of CEA-like protein on the surface of CT-26 tumors. Subsequent examination of the cross-reactivity of anti-NLGP antibody with purified or cell bound CEA revealed prominent recognition of CEA by anti-NLGP antibody, as detected by ELISA, Western Blotting and immunohistochemistry. This recognition seems to be responsible for anti-tumor function of anti-NLGP antibody only on CEA-like protein expressing CT-26 tumor models, as confirmed by ADCC reaction in CEA(+) tumor systems where dependency to anti-NLGP antibody is equivalent to anti-CEA antibody. Obtained result with enormous therapeutic potential for CEA(+) tumors may be explained in view of the epitope spreading concept, however, further investigation is crucial.
authors.affiliation: Clinical Biochemistry Unit, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India; Department of Immunoregulation and Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India.
authors.forename: Arnab
authors.initials: A
authors.lastname: Das
authors.affiliation: Department of Immunoregulation and Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India.
authors.forename: Subhasis
authors.initials: S
authors.lastname: Barik
authors.affiliation: Department of Immunoregulation and Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India.
authors.forename: Anamika
authors.initials: A
authors.lastname: Bose
authors.affiliation: Department of Immunoregulation and Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India.
authors.forename: Soumyabrata
authors.initials: S
authors.lastname: Roy
authors.affiliation: Department of Surgical Oncology and Medical Oncology, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India.
authors.forename: Jaydip
authors.initials: J
authors.lastname: Biswas
authors.affiliation: Department of Immunoregulation and Immunodiagnostics, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India. Electronic address: rathindranath.baral@cnci.org.in.
authors.forename: Rathindranath
authors.initials: R
authors.lastname: Baral
authors.affiliation: Clinical Biochemistry Unit, Chittaranjan National Cancer Institute (CNCI), 37, S. P. Mukherjee Road, Kolkata 700026, India. Electronic address: psmarajit@hotmail.com.
authors.forename: Smarajit
authors.initials: S
authors.lastname: Pal
mesh_terms: D000818:Animals; D000906:Antibodies / Q000008:administration & dosage / Q000276:immunology / Q000494:pharmacology*; D000920:Antibody-Dependent Cell Cytotoxicity; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology; D031601:Azadirachta; D002272:Carcinoembryonic Antigen / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D002277:Carcinoma / Q000188:drug therapy / Q000235:genetics* / Q000276:immunology / Q000401:mortality / Q000473:pathology; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D005260:Female; D006023:Glycoproteins / Q000037:antagonists & inhibitors* / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology / Q000494:pharmacology; D008546:Melanoma, Experimental; D051379:Mice; D018515:Plant Leaves; D010940:Plant Proteins / Q000037:antagonists & inhibitors* / Q000276:immunology; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D000906:Antibodies; D000970:Antineoplastic Agents; D002272:Carcinoembryonic Antigen; D006023:Glycoproteins; D007074:Immunoglobulin G; D010940:Plant Proteins
keywords: Antibody-dependent cellular cytotoxicity; CEA-like protein; Carcinoembryonic antigen; Colon cancer; Neem leaf glycoprotein; Polyclonal antibody