Immunological effects of occupational exposure to lead (Review).
It is well-known that occupational and environmental exposure to several factors, including benzene, heavy metals, chemicals and mineral fibers, is associated with the risk of developing a great number of diseases. Numerous studies have been carried out in order to investigate the mechanisms of toxicity of these substances, with particular regard to the possible toxic effects on the immune system. However, little is known about the influence of heavy metals, such as lead, on the immune system in human populations. Lead is a heavy metal still used in many industrial activities. Human exposure to lead can induce various biological effects depending upon the level and duration of exposure, such as toxic effects on haematological, cardiovascular, nervous and reproductive systems. Several studies demonstrated that exposure to lead is associated to toxic effects also on the immune system, thus increasing the incidence of allergy, infectious disease, autoimmunity or cancer. However, the effects of lead exposure on the human immune system are not conclusive, mostly in occupationally exposed subjects; nevertheless some immunotoxic abnormalities induced by lead have been suggested. In particular, in vivo, in vitro and ex vivo lead is able to improve T helper 2 (Th2) cell development affecting Th1 cell proliferation. Further studies are required to better understand the mechanisms of lead immunotoxicity and the ability of lead to affect preferentially one type of immune response.
Department of Biomedical, Odontoiatric, Morphological and Functional Images, Section of Occupational Medicine, 'Policlinico G. Martino' Hospital, University of Messina, I-98125 Messina, Italy.
Concettina
C
Fenga
Department of Biomedical, Odontoiatric, Morphological and Functional Images, Section of Occupational Medicine, 'Policlinico G. Martino' Hospital, University of Messina, I-98125 Messina, Italy.
Silvia
S
Gangemi
Department of Biomedical and Biotechnological Sciences, Laboratory of Translational Oncology and Functional Genomics, Section of General and Clinical Pathology and Oncology, University of Catania, I-95124 Catania, Italy.
Valentina
V
Di Salvatore
Department of Biomedical and Biotechnological Sciences, Laboratory of Translational Oncology and Functional Genomics, Section of General and Clinical Pathology and Oncology, University of Catania, I-95124 Catania, Italy.
Luca
L
Falzone
Department of Biomedical and Biotechnological Sciences, Laboratory of Translational Oncology and Functional Genomics, Section of General and Clinical Pathology and Oncology, University of Catania, I-95124 Catania, Italy.
Massimo
M
Libra
D016207:Cytokines / Q000378:metabolism; D004785:Environmental Pollutants / Q000633:toxicity*; D006801:Humans; D007107:Immune System / Q000187:drug effects*; D016273:Occupational Exposure; D017382:Reactive Oxygen Species / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D058504:Th17 Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000187:drug effects / Q000276:immunology / Q000378:metabolism
D016207:Cytokines; D004785:Environmental Pollutants; D017382:Reactive Oxygen Species