The effect of rhG-CSF on the conformation of LFA-1 on CD4⁺ T cells in hemopoietic stem cell transplantation

Abstract

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) modulates donor T cell function in hemopoietic stem cell transplantation. The effects of rhG-CSF on the activation of CD4⁺ T cells have been poorly investigated. We investigated whether rhG-CSF mobilization influenced the activation and proliferation capacity of CD4⁺ T cells. Cell treatment with phorbol 12-myristate 13-acetate (PMA) plus ionomycin or the CD3 mAb OKT3 plus intercellular cell adhesion molecule-1 (ICAM-1) at 37°C for 6 h induced a dramatic increase in CD25, CD69 and MEM148 epitope exposure. rhG-CSF mobilization decreased CD25, CD69 and MEM148 epitope expression on activated CD4⁺ T cells compared with cells before mobilization. The transcription factor Jun activation domain-binding protein 1 (JAB1) plays a role in the activation of CD4⁺ T cells, and the rhG-CSF mobilization changed the level of nuclear JAB1 protein. rhG-CSF mobilization also decreased the adhesion of CD4⁺ T cells to ICAM-1, but had no effect on the levels of donor CD4+CD25+ regulatory T cells. Overall, these data suggest the rhG-CSF mobilization can influence CD4⁺ T cell activation through LFA-1/ICAM-1 costimulatory signaling in HSC transplantation.

Keywords::

• rhG-CSF
• PMA
• OKT3
• MEM148
• CD⁴⁺
• T cells

Acknowledgments

We thank Dr Wang Lisheng of the Academy of Military Medical Sciences for guidance in performing Western blots and fluorescence microscopy. This work was supported by grants from the National Natural Science Foundation of China (No. 30570776).

Declaration of interest: The authors report no conflicts of interest.