[Impact of excessive blood-lead levels on T cell subsets in lead exposed workers].

The aim of this study was to explore the impact of lead poisoning on immunological function of T cell subsets in lead-exposed workers through analysis of clinical cases so as to provide the basis for prevention and treatment of occupational diseases. 70 cases who had excessive level of lead in blood and urine and need treatment by driving out lead were collected as observation group through detection of a large blood and urine samples from 2007 to 2010, meanwhile 60 normal healthy people without lead exposure were enrolled in control group. The blood and urine-lead level and T cell subsets in these two groups were detected and analyzed by JP-1A polarograph and flow cytometry respectively. The results showed that among 70 workers in observation group 47.14% had lower CD3(+)CD4(+) level, 71.43% had lower CD4(+)/CD8(+) ratio, the ratio-inversed cases reached to 41.42%, while 13.33% people had lower CD3(+)CD4(+) level, 25% had CD4(+)/CD8(+) ratio below normal level in control group. The blood-lead concentration and CD4(+)/CD8(+) ratio in observation group were (4.63 ± 1.27) µmol/L and 1.20 ± 0.50 respectively; the blood-lead concentration and CD4(+)/CD8(+) ratio in control group were (0.72 ± 0.35) µmol/L and 1.75 ± 0.62, respectively. It is concluded that the obvious increase of cases with cellular immune dysfunction are observed in occupational workers with excessive blood lead, indicating that the lead can suppress human cellular immune function. Moreover along with increase of blood lead concentration of these workers, more people has abnormal T cell subsets, which shows that the blood lead concentration is associated with immune function of T-cells.