A novel monoclonal antibody of human stem cell factor inhibits umbilical cord blood stem cell ex vivo expansion

Xinxin Ding,Jie Fan,Yongping Jiang

doi:10.1186/1756-8722-5-73

Abstract

Stem cell factor (SCF) activates hematopoietic stem cell (HSC) self-renewal and is being used to stimulate the ex vivo expansion of HSCs. The mechanism by which SCF supports expansion of HSCs remains poorly understood. In cord blood ex vivo expansion assays, a newly produced anti-SCF monoclonal antibody (clone 23C8) was found to significantly inhibit the expansion of CD34+ cells. This antibody appears to bind directly to a part of SCF that is critical for biological activity toward expansion of CD34+ cells, which is located in the first 104 amino acids from the NH2-terminus.

Highlights

Stem cell factor (SCF) activates hematopoietic stem cell (HSC) self-renewal and is being used to stimulate the ex vivo expansion of hematopoietic stem cells (HSCs)
Letter to the editor The stem cell factor (SCF) is a principal cytokine involved in the expansion and differentiation of hematopoietic stem cells (HSCs) [1]
When 23C8 was added together with recombinant human SCF (rhSCF), the expansion index was reduced in an antibody concentration-dependent manner; at a molar ratio of monoclonal antibodies (mAb) to rhSCF equal to or higher than 0.5, the activity of rhSCF was completely blocked

Summary

Introduction

Stem cell factor (SCF) activates hematopoietic stem cell (HSC) self-renewal and is being used to stimulate the ex vivo expansion of HSCs. Letter to the editor The stem cell factor (SCF) is a principal cytokine involved in the expansion and differentiation of hematopoietic stem cells (HSCs) [1]. The combined use of SCF and other cytokines can effectively stimulate the ex vivo expansion of umbilical cord blood CD34+ cells [2,3,4]. A better understanding of SCF’s action may help to further optimize systems for ex vivo expansion of HSCs. Using a prokaryotic expression system, we obtained recombinant human SCF (rhSCF) for preparation of monoclonal antibodies (mAb) [5].

Results

Conclusion