Intestinal Mast Cells and Globule Leucocytes: Role of the Thymus on Their Presence and Proliferation during a Trichinella spiralis Infection in the Rat

Abstract

The effect of treatment with anti-thymocyte serum (ATS) or neonatal thymectomy with or without thymus reconstitution on the presence and proliferation of intestinal mast cells (IMC) and globule leucocytes (GL) was studied in the small intestine of the rat during and oral Trichinella spiralis infection. ATS exerted an initial transient inhibitory effect on the IMC response and a marked inhibitory effect on the GL response to an oral Trichinella infection. Neonatal thymectomy decreased numbers of IMC but not of GL in the non-infected rat. Thymus reconstitution restored IMC numbers, however, not to normal values. The IMC response to Trichinella was comparable in thymectomized, thymectomized and reconstituted and intact animals. In contrast, the degree of GL response to Trichinella depended mainly on the presence of a thymus. The combined results were interpreted in favour of the hypothesis that the origin of IMC is thymus (T)-dependent, and the response to Trichinella thymus independent. No evidence for the hypothesis that subepithelial IMC are precursors for the intra-epithelially located GL was found. The latter were regarded as an independent cell population, its origin being thymus independent, and its reaction to Trichinella mainly thymus dependent.