Mercury inducible resistance

Kosuda, L.L.et al., (1994) Role of RT6+ T lymphocytes in mercury-induced renal autoimmunity Experimental manipulations of susceptible and resistant rats. J. Toxicol. Environ. Health, 42, 303, 1994. 

Zargari, A., Gharibdoost, F., DePierre, J.W. and Flassan, M. (2005) Bacterial lipopolysaccharide both renders resistant mice susceptible to mercury-induced autoimmunity and exacerbates such autoimmunity in susceptible mice. Clinical and Experimental Immunology, 141, 238-247. 

Kosuda LL, Greiner DL, Bigazzi PE. 1993. Mercury-induced renal autoimmunity changes in rt6+ T-lymphocytes of susceptible and resistant rats. Environ Health Perspectives 101(2) 178-185. 

Kosuda LL, Hosseinzadeh H, Greiner DL, et al. 1994. Role of rt6+ T lymphocytes in mercury-induced renal autoimmunity experimental manipulations of "susceptible" and "resistant" rats. J Toxicol Environ Health 42(3) 303-321. 

Rodent susceptibility to the systemic autoimmunity induced by mercury(II) chloride is genetically controlled (see chapter 7). Both MHC class II genes and non-MHC genes determine responsiveness (Hultman et al., 1996 Hanley et al., 1998 Schuppe et al., 1998 Abedi-Valugerdi Moller, 2000 Hultman Nielsen, 2001). The induction and development of autoimmune responses in susceptible strains vary across species. Rats become resistant to mercury-induced autoimmunity after a subsequent challenge, whereas mice do not show resistance to subsequent mercury exposures (see also chapter 10). 

Autoimmune-like phenomena in Brown Norway rats induced by mercuiy(II) chloride peak around day 10 after the last of five subcutaneous injections. After 20 days, immune alterations are mostly at control level, and the kidney effects (e.g. proteinuria) are clearly less than on day 10 (Aten et al., 1988). In addition, low-dose pretreatment of Brown Norway rats with mercuiy(II) chloride prevents development of adverse immunity (Szeto et al., 1999), and neonatal injection of mercury(II) chloride in Brown Norway rats renders them tolerant to mercury-induced (but not gold-induced) autoimmune phenomena (Field et al., 2000). These phenomena, transience of autoimmune effects as well as low-dose protection, are shown to be due at least in part to the development of regulatory immune cells. In the case of mercury(II) chloride, these cells have been identified as either IFN-y-producing CD8+CD45RC high regulatory T cells (Pelletier et al., 1990 Mathieson et al., 1991 Szeto et al., 1999 Field et al., 2003) or RT6.2+ T cells (Kosuda et al., 1994). In view of this, it is relevant to note that Lewis rats that produce predominantly CD8+ regulatory T cells ( suppressor T cells) in response to mercury(II) chloride are resistant to mercury-induced autoimmunity and instead display a polyclonal immunosuppressive response (Pelletier et al., 1987). Based on these differences in strain sensitivity, it is clear that susceptibility to mercury-induced autoimmune effects is dependent on MHC class II haplo-type (Aten et al., 1991). 

Resistance of LEW rats to mercury-induced autoimmunity is due neither to CD8+ suppressor cells since treatment with an anti-CD8 mAb does... 

Resistance to the toxic effects of mercury is quite commonly found in bacteria (Silver and Walderhaug 1992 Misra 1992). Since most bacteria are rarely exposed to toxic levels of mercury, the resistance mechanism is inducible and is frequently found on plasmids and/or transposons. Many of the multi-antibiotic resistance plasmids that are frequently found in clinical collections have determinants of mercury resistance as well. Furthermore, mercury resistance is a consistent component of the chromosomal resistance determinant of MRS A (methicillin-resistant Staphylococcus aureus), a current clinical problem and one with no apparent connection to the use of mercurials. If the mercury resistance system is present, the expression of the detoxifying activities is tightly regulated and turned on only when needed. The MerR regulatory protein turns on mRNA synthesis by a positive activator mechanism (for primary references, see Silver and Walderhaug 1992 Misra 1992). 

Dilatometer. Reliable kinetic data on gamma-induced emulsion polymerization can be obtained only when the polymerization rate is measured continuously (7). The recording dilatometer used in our previous work had some disadvantages. A mercury meniscus traveled down a precision capillary, releasing a thin platinum wire within the capillary. The electrical resistance of this assembly was used as a measure for the... 

Amongthe Enterobacteriaceae, plasmids may carry genes specifying resistance to antibiotics and in some instances to mercury, organomercury and other cations and some anions. Mercury resistance is inducible and is not the result of training or tolerance. Transposon (Tn)501, conferring mercury resistance, has been widely studied. Plasmids conferring resistance to mercury are of two types ... 

Dubey C, Bellon B, Hirsch F, et al. 1991a. Increased expression of class II major histocompatibility complex molecules on B cells in rats susceptible or resistant to mercury chloride-induced autoimmunity. Clin Exp Immunol 86(1) 118-123. 

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