Objective: To investigate the expressions of T cell receptor (TCR) signaling CD3γ, CD3δ and CD3epsilon chains in T cells from peripheral blood mononuclear cells (PBMCs) in lead-poisoned workers after chelate treatment.
Methods: The expression levels of CD3γ, CD3δ and CD3epsilon mRNAs in PBMCs from 16 lead-poisoned workers before and after chelate treatment and 9 healthy individuals were detected by real-time quantitative PCR. The β2-microglobulin gene (β2M) was used as an endogenous reference. Relative mRNA levels were calculated by the 2(-δCt)×100%. Spearman correlation analysis was used to estimate the correlations of different gene expression levels between healthy individuals and the patients as well as before and after the treatment.
Results: The CD3γ mRNA level in the lead-poisoned workers before and after chelate treatment has no significant difference as compared with that of the healthy individuals. The expression levels of CD3δ mRNA in the lead-poisoning workers before and after chelate treatment were remarkably lower than that of the healthy individuals. After chelate treatment, the CD3δ mRNA level in the lead-poisoned workers was lower than that before treatment. The CD3epsilon mRNA level in the lead-poisoned workers before treatment was obviously higher than that of the healthy individuals, while the expression level of CD3epsilon mRNA decreased after chelate treatment. There were no evident correlations between CD3γ and CD3δ, CD3γ and CD3epsilon, CD3δ and CD3epsilon mRNAs, while CD3γ and CD3δ, CD3γ and CD3epsilon, CD3δ and CD3epsilon mRNAs had markedly positive correlations in the lead-poisoned workers before chelate treatment, and only CD3δ and CD3epsilon had a significantly positive correlation after the treatment.
Conclusion: The expression levels of CD3γ, CD3δ and CD3epsilon mRNAs in the lead-poisoned workers showed varied alterations, which indicated that lead poisoning had an impact on human immunity system and affected different genes in different ways. After chelate treatment, CD3δ mRNA level was still different from that of healthy individuals, which indicated that the function of the immunity system was still abnormal.