Distribution and force spectroscopy of CD20 antigen-antibody binding on the B cell surface.
- Author:
Qiulan WANG
1
;
Yuhong LU
;
Shengpu LI
;
Mu WANG
;
Jiye CAI
Author Information
1. Department of Chemistry, Jinan University, Guangzhou 510632, China.
- Publication Type:Journal Article
- MeSH:
Antigen-Antibody Reactions;
immunology;
Antigens, CD20;
immunology;
B-Lymphocytes;
immunology;
ultrastructure;
Binding Sites, Antibody;
Cell Membrane;
immunology;
Humans;
Leukemia, Lymphocytic, Chronic, B-Cell;
immunology;
Microscopy, Atomic Force;
Microscopy, Confocal;
Quantum Dots
- From:
Chinese Journal of Biotechnology
2011;27(1):131-136
- CountryChina
- Language:Chinese
-
Abstract:
The lower expression of CD20 antigen molecules on the B cell membrane is the primary characteristic of B-chronic lymphocytic leukemia (B-CLL). In this paper, we combined laser scanning confocal microscopy (LSCM) and quantum dots labeling to detect the expression and distribution of CD20 molecules on CD20+B lymphocyte surface. Simultaneously, we investigated the morphology and ultrastructure of the B lymphocytes that belonged to the normal persons and B-CLL patients through utilizing the atomic force microscope (AFM). In addition, we measured the force spectroscopy of CD20 antigen-antibody binding using the AFM tips modified with CD20 antibody. The fluorescent images indicated that the density of CD20 of normal CD20+B lymphocytes was much higher than that of B-CLL CD20+B cells. The AFM data show that ultrastructure of B-CLL CD20+B lymphocytes became more complicated. Moreover, the single molecular force spectroscopy data show that the special force of CD20 antigen-antibody was four times bigger than the nonspecific force between the naked AFM tip and cell surface. The force map showed that CD20 molecules distributed homogeneously on the normal CD20+B lymphocytes, whereas, the CD20 molecules distributed heterogenous on B-CLL CD20+B lymphocytes. Our data provide visualized evidence for the phenomenon of low-response to rituximab therapy on clinical. Meanwhile, AFM is possible to be a powerful tool for development and screening of drugs for pharmacology use.
