ABSTRACT
The PLNA was introduced by the seminal paper of Helga Gleichmann, who showed that the injection of the anticonvulsant drug phenytoin into a hind footpad of mice signi cantly increased the weight of the draining PLN compared with the contralateral untreated PLN [4]. The ndings in animal models of graft-versus-host (GvH) reactions and the clinical signs and symptoms of phenytoin hypersensitivity in man are strongly reminiscent of a GvH disease [5]. Gleichmann et al. [6] hypothesized that GvH-like T-cell reactions could be mounted toward adjacent lymphocytes rendered histoincompatible following phenytoin administration. As Ford et al. [7] had previously shown that the injection of histoincompatible lymphocytes into the footpad of rats produced a regional GvH reaction evidenced by PLN enlargement, the induction of increased PLN weight by phenytoin injection to mice lent support to the (pseudo-)GvH hypothesis of phenytoin hypersensitivity and paved the way for further development of the PLNA [8,9].
