Lead exposure affects inflammatory mediators, total and differential white blood cells in sensitized guinea pigs during and after sensitization.

Background: Serum inflammatory mediators and white blood cells (WBC) counts in the blood of sensitized and lead exposed guinea pigs were evaluated.

Methods: Guinea pigs were randomly allocated into control (C), sensitized (S) and sensitized groups exposed to three lead concentrations (0.1, 0.2 and 0.4 M) during (DS) and after sensitization (PS), (n = 6 for each group). Animals were sensitized by intra-peritoneal injection and aerosol inhalation of ovalbumin (OA). Serum total protein, PLA2, IgE, histamine, total and differential WBC counts of blood were evaluated.

Results: Serum PLA2, total protein, IgE, histamine, total and differential WBC counts in all three sensitized groups were significantly increased, but the percentage of lymphocyte was decreased compared to control group (p < 0.05 to p < 0.001). Serum total protein and total WBC number in all animals exposed to lead as well as the eosinophil and histamine in animals exposed to highest lead concentration and IgE in sensitized groups exposed to lead after sensitization were significantly higher, but the lymphocyte in animals exposed to two higher lead concentrations was lower than non exposed sensitized group (p < 0.05 to p < 0.001). The changes in all parameters in lead exposed animals after sensitization were higher than those during sensitization which was statistically significant for total WBC count in the animals exposed to low lead concentration (p < 0.05).

Conclusion: Inhaled lead can increase serum total protein, PLA2, IgE and histamine levels, total and most differential WBC counts in sensitized animal which was more pronounced in animals exposed to lead after compared to those during sensitization.