Effects of ETS on Respiratory Health

There exists a significant body of research on the potential effects on respiratory health from exposure to environmental (passive) tobacco smoke (ETS) (reviewed in National Academy of Sciences 2000). Many components of ETS are known lung irritants. There have been direct associations shown between exposure to tobacco smoke and the development of lung cancer, obstructive airway disease, chronic bronchitis, ear infections, and asthma. It is small wonder that ETS is associated with so many...

Development Of The Newborn Immune System

Upon parturition, the immune system of the neonate becomes abruptly released from the immunosuppressive intrauterine environment (Holt 2003 Janeway Jr. et al. 1997b West 2002) and is concomitantly exposed to a world of antigens. Unlike the situation in rodents, the human neonatal immune system has achieved a significant level of maturity (Holt and Jones 2000 Peakman et al. 1992 West 2002). However, in comparison with the human adult immune system and with respect to the antigenic challenges...

Heavy Metals

The immunotoxic effects of heavy metals, such as lead, arsenic, and mercury exposure are well recognized (Bernier et al. 1995 Schuppe et al. 1998). In comparison to most environmental toxicants, the mechanism of metal immunotoxicity is well studied (reviewed in Schuppe et al. 1998). It is currently believed that metals initially elicit a cell-mediated immune response by binding to MHC class II molecules or MHC-bound self-peptides. The metal-MHC complex is then recognized by CD4+ T cells....

Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are a group of unsaturated cyclic hydrocarbons containing two or more rings, derived from the incomplete burning of organic materials. They are common environmental contaminants produced by diverse industrial (Ball and Dawson 1969 Ball et al. 1966 Gricuite 1979) and domestic (Huhti 1981 Aggarwal et al. 1982 Grimmer and Pott 1983) processes. Contamination and exposure to PAHs can occur in industrial, rural, and urban settings, as PAHs can be found in...

Common Effects of TCDD and CsA on T Cell Development

The developing immune system has been demonstrated to have a high sensitivity to TCDD. This, coupled with evidence that increased autoimmune disease may result following TCDD exposure in adult animals, has raised questions regarding possible relationships between prenatal exposure to TCDD and increased postnatal autoim-munity. Low-level maternal TCDD exposure results in atrophy of the developing thymus as well as inhibition of thymocyte differentiation (Table 13.2). T-progenitor cells from the...

Manipulators Of The Developing Immune System

The immune system matures according to developmental pathways but also in response to the environment. Four manipulators impact many facets of the immune system and deserve attention. First and foremost, nutrition plays a vital role in the ability of the body to defend against pathogens (Bardare et al. 1993 Devereux et al. 2002). The majority of immunocompromised individuals in the world simply lack nourishment (Janeway Jr. et al. 1997a). Studies implicate maternal diet in development of atopic...

Introduction Therapeutic Immunosuppressant Use In Women Of Childbearing

Women receiving organ transplants or suffering from cancer or autoimmune disease are the most common candidates for therapeutic immunosuppressive drug regimens during pregnancy (Forastiere et al. 2003 Tournigand et al. 2003 Hurtova et al. 2001 Millan et al. 2003). The chemotherapeutic drugs used to treat cancer are not administered with the intent of causing immune suppression. However, many chemotherapeutic agents (e.g., cyclophosphamide, chlorambucil, methotrexate, 0-415-28457-0 05 0.00+ 1.50...

Pyrethroid Insecticides Cypermethrin

Cypermethrin is a widely used synthetic type II pyrethroid insecticide due to its high insect toxicity, low mammalian toxicity, and rapid metabolism (Crawford et al. 1981 Rhodes et al. 1984). Cypermethrin is primarily considered to be a sodium channel toxin. At high concentrations, pyrethroids induce a long-lasting depolarization and block nerve conduction. However, other secondary mechanisms of action are also involved in their toxicity, including antagonism of GABA inhibitory action,...

Alcohol

A number of studies have shown that consumption of alcohol inhibits immune function in both adult humans and animals (Jerrells et al. 1986). In adults, ethanol is immunosuppressive, decreasing both the cellularity of the thymus and spleen and interfering directly with B and T-lymphocyte responses. Additionally, alcohol suppresses the phagocytic activity of macrophages and reduces NK cell activity (Seelig et al. 1996). Ethanol consumption alters cytokine production, including IL-2, IL-5, IL-6,...

Signaling Pathways and Transcription Factors Involved in Asthma Pathogenesis

Soluble mediators may play important roles in the sensitization and triggering of asthmatic responses, but they only do so by acting through specific receptors. Binding to a specific receptor by any cognate ligand normally transduces a signal to the nucleus to transcribe, or block the transcription of, a gene or genes via one or more intracellular biochemical pathways. Steps along a pathway are referred to as pathway intermediates, and those intermediates directly responsible for binding to DNA...

Asthmatic Inflammation

Asthma is a chronic inflammatory disease of the airways. Asthmatic inflammation involves complex interactions between the cytokines and signaling pathways of many cell types. In adults and children, T cells are known to be integrally involved in this process (Azzawi et al. 1990 Corrigan and Kay 1990 Wardlaw et al. 1988). The maintenance of airway inflammation is attributed, in adults, to chronically activated memory T cells sensitized against a variety of allergens (Corrigan and Kay 1990) and,...

Ochratoxin A

Ochratoxin A is a mycotoxin produced by Aspergillus ochraceus and Penicillium verrucosum and is found worldwide as a food contaminant. It is known to cause porcine nephropathy and may be associated with a human kidney disease endemic to the Balkan region Bondy and Pestka 2000 . Mice and rats exposed to ochratoxin A in utero had altered immune responses compared to controls. A single dose of och-ratoxin A 10 to 500 mg kg to pregnant mice decreased thymic CD4 and increased thymic CD4 CD8...

Therapeutic Immunosuppressant Levels In Mammary Gland Secretions

Many of the immunosuppressive drugs used during pregnancy are also found in breast milk. Currently, the American Academy of Pediatrics AAP provides guidelines for breastfeeding based on the excretion rate and potential teratogenic effects of each drug Tendron et al. 2002 . For example, limited concentrations lt 10 of prednisone and prednisolone have been measured in breast milk, levels perceived by the AAP as nonthreatening to the breastfed infant Coulam et al. 1982 Ost et al. 1985 . Thus,...

References

Blaylock BL, Holladay SD, Comment CE, Heindel JJ, and Luster MI. 1992. Exposure to tetrachlorodibenzo-p-dioxin TCDD alters fetal thymocyte maturation. Toxicol Appl Pharmacol 112 207-213. Chapin RE, Harris MW, Davis BJ, Ward SM, Wilson RE, Mauney MA, Lockhart AC, Smialowicz RJ, Moser VC, Burka LT, and Collins BJ. 1997. The effects of perinatal juvenile methoxychlor exposure on adult rat nervous, immune, and reproductive system function. Fundam Appl Toxicol 40 138-157. Dietert RR, Etzel RA, Chen...

The Pigs Intestinal Immune System During Postnatal Development

The early postnatal development of the gut immune system is important for effective immunological responses towards nutritional and microbial antigens in the intestinal lumen. Adaptation to the commensal flora, defense against pathogens, and the development of oral tolerance to food components are essential immunological processes. Depending on the food composition and on the presence of oral food components, the morphology of both the intestinal mucosa and the intestinal immune cells changes...

Diazepam Valium

Diazepam DZP is a benzodiazepine BDZ with central nervous system CNS -depressant properties. It has anxiolytic, sedative hypnotic, muscle relaxant, and anticonvulsant effects. DZP is used in humans for the short-term relief of symptoms related to anxiety disorders the treatment of agitation, tremors, delirium, seizures, and hallucinations as a result of alcohol withdrawal the relief of muscle spasms in certain neurological diseases and the control of active seizures Costa and Guidotti 1979 ....

Proposed Content Of A Developmental Immunotoxicity Study

Although the need for developmental immunotoxicity testing has long been recognized by the scientific and regulatory communities NRC 1993b USEPA 1999, 2002b , there is currently no formal EPA testing guideline protocol for this study. Studies have, however, been conducted in numerous laboratories to assess the developmental immunotoxic potential for a myriad of pharmaceuticals, pesticides, and environmental pollutants. Additionally, the National Toxicology Program NTP has devised an...