Intestinal Mast Cells and Globule Leucocytes: Role of the Thymus on Their Presence and Proliferation during a <i>Trichinella spiralis</i> 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.

Effect of Fixation on the Light Microscopical Visualization of Mast Cells in the Mucosa and Connective Tissue of the Human Duodenum

“…Since also in the rat intestine two types of mast cells have been observed [2,6,11,17], which differed in fixation and staining characteristics, we studied whether this also was true for the human intestine. For this purpose we studied a series of human biop sies from the duodenum, fixed in two fixatives earlier shown to be essential for the differentiation of MMC and CTMC in rat and monkey intestine.…”

“…Studies in congenitally athymic (nude) mice [10] and T cell-depleted and athymic rats [6,11,17] have shown the thymus dependence of the proliferation of mucosal mast cells (MMC). MMC differ from con nective tissue mast cells (CTMC) in fixation and staining characteristics as has been described for the rat [1,2] and the mouse [10].…”

Importance of immunoglobulin E (IgE) in the protective mechanism against gastrointestinal nematode infection: looking at the intestinal mucosae

“…The three hallmarks of the immune response triggered by gastrointestinal (GI) nematode infection are eosinophilia, intestinal mastocytosis and IgE production (JARRETT & MILLER, 1982;LOVE et al, 1976;RUITENBERG et al, 1979). These responses are regulated, in humans and mice, by cytokines produced by a T helper cell subset designated Th-2 (MOSMANN & COFFMAN, 1989).…”

Mast Cell Stabilizer Ketotifen [4-(1-Methyl-4-piperidylidene)-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-10(9H)-one Fumarate] Prevents Mucosal Mast Cell Hyperplasia and Intestinal Dysmotility in Experimental Trichinella spiralis Inflammation in the Rat

“…In the meantime, there is a strong motor and secretory reaction that promotes worm expulsion and restoration of health (Palmer et al, 1984;Wang et al, 1991). These changes are concomitant with a severe mast cell hyperplasia that also decreases spontaneously after worm expulsion (Ruitenberg et al, 1979).…”