Identification of novel tumor antigens with patient-derived immune-selected antibodies |
| |
Authors: | Daniel Rodriguez-Pinto Jason Sparkowski Martin P Keough Kathryn N Phoenix Frank Vumbaca David K Han Eckart D Gundelfinger Philip Beesley Kevin P Claffey |
| |
Institution: | (1) Center for Vascular Biology, EM028, Department of Cell Biology-MC3501, University of Connecticut Health Center, 263 Farmington Ave., Farmington, CT 06030-3501, USA;(2) The Feinstein Institute for Medical Research, Manhasset, NY 11030, USA;(3) Merck &; Co, Inc., Upper Gwynedd, PA 19454, USA;(4) Gene Therapy Program, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA;(5) Leibniz Institute for Neurobiology, Magdeburg, Germany;(6) School of Biological Sciences, Royal Holloway University of London, Surrey, UK; |
| |
Abstract: | The identification of tumor antigens capable of eliciting an immune response in vivo may be an effective method to identify
therapeutic cancer targets. We have developed a method to identify such antigens using frozen tumor-draining lymph node samples
from breast cancer patients. Immune responses in tumor-draining lymph nodes were identified by immunostaining lymph node sections
for B-cell markers (CD20&CD23) and Ki67 which revealed cell proliferation in germinal center zones. Antigen-dependent somatic
hypermutation (SH) and clonal expansion (CE) were present in heavy chain variable (VH) domain cDNA clones obtained from these
germinal centers, but not from Ki67 negative germinal centers. Recombinant VH single-domain antibodies were used to screen
tumor proteins and affinity select potential tumor antigens. Neuroplastin (NPTN) was identified as a candidate breast tumor
antigen using proteomic identification of affinity selected tumor proteins with a recombinant VH single chain antibody. NPTN
was found to be highly expressed in approximately 20% of invasive breast carcinomas and 50% of breast carcinomas with distal
metastasis using a breast cancer tissue array. Additionally, NPTN over-expression in a breast cancer cell line resulted in
a significant increase in tumor growth and angiogenesis in vivo which was related to increased VEGF production in the transfected
cells. These results validate NPTN as a tumor-associated antigen which could promote breast tumor growth and metastasis if
aberrantly expressed. These studies also demonstrate that humoral immune responses in tumor-draining lymph nodes can provide
antibody reagents useful in identifying tumor antigens with applications for biomarker screening, diagnostics and therapeutic
interventions. |
| |
Keywords: | Neuroplastin/SDR-1 Tumor antigen Germinal center Immune response Breast cancer Sentinel lymph node |
本文献已被 PubMed SpringerLink 等数据库收录! |
|