Delayed type cutaneous hypersensitivity

Allergy a hypersensitivity of the immune apparatus s pathological immune reaction induced either by antibodies (immediate hypersensitivity) or by lymphoid cells (delayed type A.). Unlike the delayed type, immediate hypersensitivity can be passively transmitted in the serum. Symptoms of immediate hy-peisensitivity begin shortly after contact and decay rapidly, but delayed type symptoms do not attain a maximum for 24-48 hours then decline slowly over days or weeks Examples of immediate type A. are anaphylaxis the Arthus reaction and serum sickness. The best known A., anaphylaxia, can occur as a local (cutaneous) reaction (e.g. a rash with blisters) or as a systemic reaction (anaphylactic shock). Asthma, hay fever and nettle rashes are also examples of local anaphylactic reactions which are induced by reagins (see Immunoglobulins IgE). Only primates can be sensitized by injection with human reagins. An example of delayed type A. is the tuberculin reaction, which is based on a cellular immune response. 

Ingested arsenic localizes to the skin [2, 7], where it may alter cutaneous immune responses. The delayed type hypersensitivity (DTH) response to 2,4-dinitrochlorobenzene (DNCB) was suppressed in Bowen s disease patients [8], Langerhans cells (LC) in skin lesions and perilesioned skin from arsenic-induced Bowen s disease and carcinomas were reduced in number and were morphologically altered, having a notable loss of dendrites [9], These data suggest that chronic exposure to arsenic in drinking water may... 

Inhibition of T cell recruitment and cutaneous delayed-type hypersensitivity-induced inflammation with antibodies to monocyte chemoattractant protein-1. Am. J. Path. 148, 855-864. 

Platt JL, Grant BW, Eddy AA, Michael AE Immune cell populations in cutaneous delayed-type hypersensitivity. J Exp Med 1983 158 1227-1242. 

Mathieu A, DiPadua D, Mills J, Kahan B (1974) Experimental immunity to a metabolite of halothane and fluroxene cutaneous delayed-type hypersensitivity. Anesthesiology 40 385-390... 

Guinea pigs were immunized repeatedly with rifampicin in complete Freund s adjuvant and skin reactions after challenge were studied (Dukor et al. 1973). There was evidence of allergic reactions of the immediate as well as of the delayed type. However, antibodies were not measured by passive cutaneous anaphylaxis or any other immunologic method. Therefore, the skin reactions observed 4 h after challenge could well have masked an incipient type of delayed hypersensitivity reaction (Dewdney 1977). Hence, these experiments do not establish unequivocally the im-munogenicity of rifampicin. 

Rand et al. (22) addressed the role of MCP-1 in a rat model of a cutaneous delayed-type hypersensitivity reaction. They observed MCP-1 expression by infiltrating neutrophils at early time points (4-8 h) following intradermal challenge and by epidermal and epithelial cells at later time points, with maximum expression at 24 h. Macrophage and T-cell recruitment peaked 2-3 d after challenge, and anti-MCP-1 antibodies inhibited the recruitment of T cells into the inflamed skin in a dose-dependent manner. In contrast, macrophage recruitment was inhibited only at the highest antibody dose. 

Rand, M. L., Warren, J. S., Mansour, M. K., Newman, W., and Ringler, D. J. (1996) Inhibition of T cell recruitment and cutaneous delayed-type hypersensitivity-induced inflammation with antibodies to monocyte chemoattractant protein-1. Am. J. Pathol. 148,855-864. 

Presentation of current knowledge of the mechanisms underlying the various systemic and cutaneous drug reactions including mechanisms of immediate, late, and delayed reactions, type II and type III hypersensitivities, and some important drug-induced sensitivities lacking an immune basis. 

Tse Y, Cooper KD. Cutaneous dermal Ia+ cells are capable of initiating delayed type hypersensitivity responses. J Invest Dermatol. 1990 94 267-72. 

Four cases of reactions to thiomersal in hepatitis B vaccines (both plasma-derived and recombinant) have been reported from two centers (79,80). Although thiomersal is present in these vaccines at a concentration of only 1 20 000, it can cause severe cutaneous reactions of the delayed hypersensitivity type, and sometimes the reactions can be very long lasting. 

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