Aim: To validate the abundance of Interleukin 8 receptor beta (IL-8Rbeta) mRNA in single human neutrophil.
Methods: Human neutrophils were isolated and purified from volunteers, total RNA was extracted and a regular RT-PCR aiming at IL-8Rbeta mRNA was performed to ascertain its expression profile in human neutrophils and optimize the reaction conditions for the following single-cell RT-PCR procedures. Subsequently, single neutrophil or the cellular content was harvested to conduct reverse transcription and two-round PCR with the same primer pairs used before. Serial dilution of single neutrophil cDNA pool was carried out at the same time with the exact two-round PCR followed. The specificity of this single-cell RT-PCR procedure was verified by the BamHI restriction endonuclease digestion on the final cDNA products.
Results: Regular RT-PCR indicated IL-8Rbeta mRNA expression in human neutrophils. While single-cell RT-PCR was sensitive enough to detect trace IL-8Rbeta mRNA as predicted cDNA product could be amplified from a 10 000 times diluted intracellular specimen from single neutrophil, which indicated an abundant expression of this mRNA in human neutrophil. Moreover, BamHI digestion on the final cDNA product clarified the specificity of this single-cell RT-PCR procedure.
Conclusion: This simplified semi-quantitative single-cell RT-PCR procedure specifically confirmed that IL-8Rbeta mRNA was highly expressed in human neutrophil, which also provided the possibility of comparing mRNA abundance at single cell level.