Changes in natural killer cell subpopulations in lead workers

Abstract

To investigate the effects of lead on human immune system, we analyzed T cell subpopulations (CD4+, CD8+ and CD3+ cells), natural killer (NK) cell subpopulations (CD16+ and CD57+ cells) and B (CD19+) cells in peripheral blood in 29 male lead workers. All were engaged in manufacturing lead stearate in a chemical factory. They were aged 23-74 (mean 49) years. Their blood lead concentrations (PbB) were between 7 and 35 (mean 18) micrograms/dl. They were divided into two groups according to their PbB: a high-PbB group (> or = 20 micrograms/dl), and a low-PbB group (< 20 micrograms/dl). The control group consisted of 19 "healthy" male workers without a history of occupational exposure to lead or to other hazardous substances, aged 48-67 (mean 58) years. The number and percentage of CD16+ cells in the high-PbB group were significantly lower than those in the controls and in the low-PbB group. There was significant negative correlation between the number of CD16+ cells and PbB in the lead workers. The percentage of CD8+ cells in the high-PbB group was larger than that in the controls and in the low-PbB group. It is suggested that the CD16+ NK cell should be a major site of the effects of lead on lymphocyte subpopulations.

Lymphocyte subpopulations in human exposure to metals (IUPAC Technical Report)

“…In contrast, Pinkerton et al [84] did not observe a difference in CD3+, CD4+, or CD8+ T, B, or NK cells in leadexposed workers with a mean blood lead level of 1.88 µmol/L, compared to unexposed individuals. CD8+ cells were even increased at blood lead levels > 0.97 µmol/L, and were accompanied by a decrease in NK cells and CD3+CD45RO+ (memory) T cells, as reported by Sata et al [85,86]. Moreover, blood lead was correlated with CD4+CD45RO-, CD3+CD8+, and CD3-HLA-DR+ lymphocyte subsets in a population of non-atopic women in an urban environment [51].…”

Decreases in CD8+ T, Naive (CD4+CD45RA+) T, and B (CD19+) Lymphocytes by Exposure to Manganese Fume

“…A possible explanation is that function of T lymphocytes especially CD4+ and CD8+ T lymphocytes are affected by chronic low-dose exposure to Mn while higher dose may affect not only function but quantity of lymphocytes. Another explanation is that the study by Colosio et al 2) measured only percentages of lymphocyte subpopulations but not absolute counts which is more sensitive to chemical agents 8,11,12,[16][17][18][19][20] . Strong inverse correlations between BMn concentrations and CD4+CD45RA+ T, CD4+ T, CD8+ T, and CD3+ T lymphocytes were found in the current study.…”

“…Exposure to lead has been reported to have a decreasing effect on immune cells such as CD4+ T lymphocytes 10) , CD3+CD45RO+ T lymphocytes 11) , and CD16+ NK cells 12) , as well as serum IgG, A and M in a relatively high level as 20 µg/dl in the peripheral blood 13) . However, the welders in this study were exposed to the welding fume from alloysteel bars containing less than 0.0036% of lead suggesting a very low level exposure to lead, which may be negligible.…”

Changes in T Cell Subpopulations in Lead Workers

“…, and mouse IgG 1 /mouse IgG 2a as a negative control (Sata et al, 1997b;Sung et al, 1995). PbB levels were measured by polarized Zeeman atomic absorption spectrophotometry (Z-8100, Hitachi, Tokyo) after 10-fold dilution with 1% ammonium phosphate and 1% Triton X solution.…”