Studies on the Sensitization of Animals With Simple Chemical Compounds

Abstract

From a survey of the literature it would appear that experimental skin sensitization with simple chemicals, unlike common anaphylactic sensitization, has been accomplished with certainty only by application of the incitant on or into the skin. Observations to this effect have been recorded by several authors. Simon et al. (1,2) state that in the course of experiments on sensitizing guinea pigs to poison ivy they had "no results except with the direct application of the extract to the skin." The same point is made by Straus (3) who found only one out of a group of 10 infants injected subcutaneously with poison ivy extract to develop sensitivity, in contrast to the more than 70 per cent positive results following cutaneous application; he remarks that it cannot be excluded that the one case might have been due to contamination of the epidermis. Similarly with neosalvarsan administered to guinea pigs, where the sensitization is not of the contact dermatitis type, Sulzberger (4) failed to obtain skin hypersensitiveness by the intramuscular, intraperitoneal, intratesticular, and intracardial routes, using a dosage effective when given intradermally. And in this laboratory preliminary experiments at sensitizing with intravenous or subcutaneous injections of 2:4 dinitroehlorobenzene were indecisive (5, 6). In fact, it is not infrequently held that skin sensitization is the result of a direct action on the epithelial cells, there inducing a specific change, and experiments which support this view have been performed by Straus and Coca (7; cf. 8) and more recently by Schreus and his coworkers (9, 10) (vide 11). There are some experiments, indeed, with apparently positive outcome after administration by non-cutaneous routes, e.g. with primula extract given intravenously (Bloch (12)) and with Japanese lacquer (Rhus vernicifera) by subcutaneous injection (Kobayashi (13)). The sensitivities so found were of lesser degree than those secured by dermal treatment, and were open to doubt since no mention is made in these reports of precautions against accidental contamination of the skin, a matter of im-

Occurrence of Delayed Hypersensitivity During the Development of Arthus Type Hypersensitivity

“…The importance of this route has been further emphasized by studies on sensitization to simple chemicals (13,14), wherein topical application in off of such substances as picryl chloride induces a delayed type of allergy. Also, when antigen-antibody complex is injected ~ia the intradermal route, greater delayed sensitivity is induced than when it is injected da the intraperitoneal, subcutaneous, or intramuscular route (1).…”

The Specificity of Allergic Reactions

“…Reactions were observed and diameters of areas of induration measured at 4 hours and at 18 to 24 hours. The strength of the contact reactions was recorded depending on the elevation and pinkness of the sites of lmpten application (8). Normal guinea pigs were simultaneously tested on the sides with lmpten, in order to serve as negative controls with which to compare experimental animals.…”

A Unique Rapid Enhancement by Adjuvant of Delayed Hypersensitivity to Protein Antigens in the Guinea Pig

“…Separate injection of antigen and adjuvant has been used previously in the production of sensitivity to simple chemical allergens and con jugates thereof as well as in the induction of autoimmune disease, such as experimental allergic encephalomyelitis [1,12,13]. A pre-requisite for the success of split-adjuvant techniques appears to be that adjuvant and antigen are injected close to one another.…”