Hypersensitive reaction, induction

The guinea pig maximization test (GPMT) is a preferred method for the detection of skin sensitizers. It belongs to the class of adjuvant-tests, where the substance will be applied in Freund s complete adjuvant (FCA). The test is based on the possible induction of an immune response of the skin during an induction period (at least 1 week). This pretreatment of the subject will eventually result in a hypersensitive reaction during a further exposure, the so-called challenging phase. 

Mucosal tolerance protection from hypersensitivity reactions towards harmless environmental and food antigens Mucosal homeostasis induction of immunoregulatory functions, maintenance of an intact endogenous micro flora... 

Demoly P, Messaad D, Fabre J, Reynes J, Bousquet J. Nevirapine-induced cutaneous hypersensitivity reactions and successful tolerance induction. J Allergy Clin Immunol 1999 104(2 Pt l) 504-5. 

In a retrospective cohort study in 83 patients with primary brain tumors who were treated with procarbazine, 20 patients had procarbazine hypersensitivity reactions (4). There was a significant association between exposure to antiepileptic drugs and the development of procarbazine hypersensitivity reactions. The authors suggested that this association may have been due to a reactive intermediate generated by induction of CYP3A. 

Contact (or chemical) hypersensitivity reactions develop in two phases induction and elicitation (Figure 1). Induction is the development of the initial sensitization. In this phase, the chemical penetrates the epidermis. Chemicals are haptens because they are, by themselves, unable to elicit an immune response. As such, they must associate with proteins in the skin to stimulate a specific immune response. The hapten-protein complex is then processed by antigen presenting cells in the skin, transported and presented to T cells in the draining lymph nodes. This interaction leads to a proliferative response and the development of memory T cells that distribute systemically within the body. 

This is particularly important when considering how the physical characteristics of the test article, including particle size and excipients, and dose can influence the outcome of induction and ehcitation of respiratory hypersensitivity reactions. 

Hypersensitivity. In addition to inducing immune dysfunction, pesticides have the potential to exert immunomodulatory effects through the induction of allergic hypersensitivity and autoimmune disease. Pesticide-related hypersensitivity reactions generally are... 

Huang, J.-S. and R.N. Goodman Relationship of phos-phatidase activity to induction of the hypersensitive reaction in tobacco plants by bacteria Trans. Mo. Acad. Sci. 3 (1969) 94, see Huang, J.-S. and R.N. Goodman The relationship of phosphatidase activity to the hypersensitive reaction in tobacco induced by bacteria Phytopathology 60 (1972) 1020-1021. 

Biologies are sufficiently large and complex as to elicit immune responses directed to the protein. For the most part, the principal response elicited is a T cell-dependent humoral response. The development of an antibody response to a biologic in most cases has no adverse consequences (Schellekens 2002a Shankar et al. 2006). An antibody response is not an adverse event in itself. However, an antibody response to a biologic can have consequences that fall into three main categories hypersensitivity reactions, reduction in efficacy, and the induction of autoimmune disease (Schellekens 2002b). 

Glucans and the Induction of the Hypersensitive Reaction. The hypersensitive reaction associated with incompatible infections is characterised by localised browning and death of infected cells. This reaction has been reproduced in tuber tissue from resistant and susceptible potato varieties by a heat-stable component isolated from P. infestans mycelium... 

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