Research article

Expression of P2 receptors in human B cells and Epstein-Barr virus-transformed lymphoblastoid cell lines

Dong Hyeon Lee¹ , Kyu Sang Park² , In Deok Kong² , Jun Woo Kim¹ and Bok Ghee Han¹

¹Biobank for Health Sciences, Center for Genome Sciences, National Institute of Health, Korea Center for Disease Control and Prevention, Seoul, South Korea

²Department of Physiology, Institute of Basic Medical Science, Yonsei University, Wonju College of Medicine, Wonju, South Korea

author email corresponding author email

BMC Immunology 2006, 7:22doi:10.1186/1471-2172-7-22

Published:	14 September 2006

Abstract

Background

Epstein-Barr virus (EBV) infection immortalizes primary B cells in vitro and generates lymphoblastoid cell lines (LCLs), which are used for several purposes in immunological and genetic studies. Purinergic receptors, consisting of P2X and P2Y, are activated by extracellular nucleotides in most tissues and exert various physiological effects. In B cells, especially EBV-induced LCLs, their expression and function have not been well studied. We investigated the expression of P2 receptors on primary human B cells and LCLs using the quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) method for revealing the gene expression profile of the P2 receptor subtypes and their changes during transformation.

Results

The mRNA transcripts of most P2 receptors were detected in primary B cells; the expression of P2X₃ and P2X₇ receptors was the lowest of all the P2 receptors. By contrast, LCLs expressed several dominant P2 receptors – P2X₄, P2X₅, and P2Y₁₁ – in amounts similar to those seen in B cells infected with EBV for 2 weeks. The amount of most P2 subtypes in LCLs or EBV-infected B cells was lower than in normal B cells. However, the amount of P2X₇ receptor expressed in LCLs was higher. Protein expression was studied using Western blotting to confirm the mRNA findings for P2X₁, P2X₄, P2X₇, P2Y₁, and P2Y₁₁ receptors. ATP increased the intracellular free Ca²⁺ concentration ([Ca²⁺]_i) by enhancing the Ca²⁺ influx in both B cells and LCLs in a dose-dependent manner.

Conclusion

These findings describe P2 receptor expression profiles and the effects of purinergic stimuli on B cells and suggest some plasticity in the expression of the P2 receptor phenotype. This may help explain the nature and effect of P2 receptors on B cells and their role in altering the characteristics of LCLs.