The immune adherence receptor CR1-like existed on porcine erythrocytes membrane.

Zhiwei Wang,Jiaoyan Cui,Na Sun,Wei Yin,Kuohai Fan,Junxing Zhao,Hongquan Li,Yaogui Sun,Junbing Jiang,Haili Ma

doi:10.1038/srep13290

Abstract

In the present study, we obtain a mouse anti-porcine complement receptor type 1 (CR1)-like monoclonal antibody (McAb) and use this McAb to verify the existence of CR1-like protein on porcine erythrocytes. Our results confirm that CR1-like protein is localized on the surface of porcine erythrocytes. Mouse immunoglobulin G inhibited the binding of serum-opsonized green fluorescent protein-expressing Escherichia coli to porcine erythrocytes. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicates that CR1-like McAb reacts with biochemically-purified porcine erythrocyte membrane fractions, with a clear band at 135 kDa to 140 kDa. We postulate that the 135 kDa to 140 kDa membrane protein is the equivalent of the porcine erythrocyte CR1-like protein.

Highlights

Human erythrocyte complement receptor type 1 (CR1), known as CD35, is a large single-chain transmembrane glycoprotein and an immune adherence (IA) receptor of complement component 3b/4b (C3b/C4b)[1,2]
These results clearly indicate the existence of CR1-like protein on the surface of porcine erythrocytes
One major band is seen at approximately 250 kDa (1# band) on SDS-PAGE, and this band demonstrates the specificity of the CR1-like monoclonal antibody (McAb)

Summary

Introduction

Human erythrocyte complement receptor type 1 (CR1), known as CD35, is a large single-chain transmembrane glycoprotein and an immune adherence (IA) receptor of complement component 3b/4b (C3b/C4b)[1,2]. Erythrocytes bind C3b, C4b, or C1q-bearing immune complexes (ICs) to their membranes via CR13. Binding of CR1 to complement components induces phagocytosis of opsonized ICs4,5. The IA of primate erythrocytes plays an important role in the clearance of ICs from the circulation. The activity of erythrocyte IA (E-IA) in nonprimates is still controversial, and if it does occur, whether it is mediated by activated complements on ICs interacting with CR1 on erythrocytes remains unclear. Our previous studies demonstrated that the activity of E-IA in chickens with infectious bursal disease virus was significantly reduced[6] and Astragalus polysaccharides increased E-IA in mice with adjuvant-induced arthritis and reduced the deposition of ICs in joint synovium[7]. Using fluorescence microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM), we demonstrated that E-IA occurs in porcine erythrocytes[8]. The objective of the current study was to prepare anti-porcine CR1-like monoclonal antibody (McAb) to further verify the existence of porcine CR1-like protein on erythrocyte membranes

Objectives

Methods

Results

Conclusion