Analysis of cell-free human α1 integrin with a monoclonal antibody to the I-domain: Detection in ocular fluid and function as an adhesion substrate

Ilan Bank, Jarmo Kapyla, Aharon Grinbaum, Ram Doolman, Jonathan Bank, Ben Ami Sela

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

The α1β1 integrin, an inserted (I) domain containing collagen receptor, is expressed in the cell surface membrane of normal and malignant cells, and may play a role in their migration through tissues or in metastatic spread. Here we report that a functional anti-human α1β1 integrin monoclonal antibody (mAb) (1B3.1) directly and specifically binds plastic bound recombinant human α1 I-domain protein containing the collagen binding site. Detection was diminished by acidification of the I-domain protein but was enhanced by increasing concentrations of Mg2+ cation. Furthermore, we detected binding of the mAb to proteins from the ocular fluids of 6 patients, with the highest concentration, corresponding to 22.1 ng/ml of I-domain, found in a sample from the eye of a patient with metastatic lung adenocarcinoma. Interestingly, we found that both SKNSH neuroblastoma cells and virally transformed human T cells adhered specifically to plastic wells coated with either immobilized collagen IV or α1 I-domain. MAb 1B3.1 inhibited adhesion to collagen IV but not to immobilized I-domain. These results suggest a novel function for cell free α1 I-domain as a substrate for cellular adhesion, which may have relevance in tumor spread in vivo.

Original languageEnglish
Pages (from-to)113-123
Number of pages11
JournalCell Communication and Adhesion
Volume8
Issue number3
DOIs
StatePublished - 2001
Externally publishedYes

Bibliographical note

Funding Information:
Supported by the Tel Aviv University Research Authority grant from the Claire and Amedee Maratier lnstitute for the Study of Visual disorders and Blindness to A. Grinbaum and 1. Bank. Address correspondence to Ilan Bank, MD, Department of Medicine, Chaim Sheba Medical Center, Tel Hashomer 52621, Israel. E-mail: ibank@post.tau.ac.il

Keywords

  • Collagen
  • I-domain
  • Integrins
  • VLA-1
  • α1β1 integrin

Fingerprint

Dive into the research topics of 'Analysis of cell-free human α1 integrin with a monoclonal antibody to the I-domain: Detection in ocular fluid and function as an adhesion substrate'. Together they form a unique fingerprint.

Cite this