Ptak W, Rozycka D, Askenase P W, Gershon R K
J Exp Med. 1980 Feb 1;151(2):362-75. doi: 10.1084/jem.151.2.362.
Three outcomes pertinent to contact sensitivity (CS) follow immunization with various forms of trinitrophenylated (TNP) substrates: (a) specific immunological unresponsiveness for CS is induced when immunization favors activation of splenic suppressor cells. This state is achieved by intravenous injection of trinitrophenyl-conjugated to various types of cells, such as peritoneal exudate cells (PEC). (b) A short-lived or evanescent form of CS is induced when immunization reduces activation of the suppressor circuit. This can be achieved by subcutaneous immunization with trinitrophenyl conjugated to syngeneic PEC, by pretreatment with cyclophosphamide to diminish suppression before intravenous immunization, or by altering the mode of antigen presentation by using TNP-substrate that has undergone phagocytosis. (c) A long-lived form of CS is induced when trinitrophenyl is presented to the immune system on skin cells either by contact skin painting with reactive trinitrophenyl, or by subcutaneous, or even intravenous injection of trinitrophenyl-conjugated epidermal cells. In fact, trinitrophenyl-conjugated epidermal cells induced CS even when the suppressor circuit was activated by intravenous coadministration of TNP-PEC. This implies that antigen presentation on epidermal cells induces sensitized cells that are relatively resistant to suppression. The cell type(s) in the skin that are primarily responsible for this potent form of antigen presentation are most likely Langerhans cells, because they can be concentrated by virtue of their Fc receptors and they are Ia positive. Thus, both the anatomical site where antigen is first encountered by the immune apparatus, as well as the nature of the cells which present the antigen, determine whether a CS response will ensue, as well as whether it will be evanescent or long-lasting.
用各种形式的三硝基苯基化（TNP）底物进行免疫后，会出现与接触性敏感（CS）相关的三种结果：（a）当免疫有利于脾抑制细胞激活时，会诱导出对CS的特异性免疫无反应性。通过静脉注射与各种类型细胞（如腹膜渗出细胞[PEC]）结合的三硝基苯基可达到这种状态。（b）当免疫降低抑制回路的激活时，会诱导出一种短暂或易消逝形式的CS。这可通过皮下注射与同基因PEC结合的三硝基苯基、在静脉免疫前用环磷酰胺预处理以减少抑制作用，或通过使用已被吞噬的TNP底物改变抗原呈递方式来实现。（c）当通过用反应性三硝基苯基接触皮肤涂漆，或通过皮下甚至静脉注射三硝基苯基化的表皮细胞，将三硝基苯基呈递给免疫系统时，会诱导出一种持久形式的CS。事实上，即使通过静脉共同给予TNP - PEC激活了抑制回路，三硝基苯基化的表皮细胞仍能诱导CS。这意味着表皮细胞上的抗原呈递会诱导出相对抗抑制的致敏细胞。皮肤中主要负责这种强效抗原呈递形式的细胞类型很可能是朗格汉斯细胞，因为它们可凭借其Fc受体进行富集且Ia呈阳性。因此，免疫装置首次遇到抗原的解剖部位以及呈递抗原的细胞性质，决定了是否会引发CS反应，以及该反应是短暂的还是持久的。
