Effect of lead exposure on lymphocyte subsets and activation markers

Abstract

Lead is a common environmental pollutant which has adverse effects on the immune system. We studied frequency of peripheral blood populations of CD4, CD8, and CD56 expressing cells and presence of activation marker (CD25) and CD45 isoforms by flow cytometry. Among 59 lead-exposed individuals (26 three-wheeler drivers, 33 battery workers) and 21 healthy controls, blood lead levels were 6.7 ± 4.5 μg/dL, 132 ± 103 μg/dL, and 4.5 ± 2.0 μg/dL, respectively. The percentage of CD4⁺ cells was significantly lower (P < 0.001) and of CD45RA⁺ cells higher (P < 0.05) in both lead-exposed groups as compared to controls. There was a significant negative correlation between the CD4⁺ cell percentage and blood lead levels and length of exposure. Our data highlight the adverse effect of lead on immune cells which may have serious consequences for those with chronic exposure to lead.

Keywords::

• Lymphocyte subsets
• CD+ cells
• CD8+ cells
• NK cells