The pattern of peripheral blood leucocyte changes in mice infected with Nematospiroides dubius

Abstract

Experiments were carried out to define the haematological changes taking place during the first six weeks of a primary infection with Nematospiroides dubius. The general pattern of changes was observed to comprise a rapid increase in circulating leucocytes (4 to 5-fold increase) which consisted of a neutropl a, lymphocytosis, monocytosis and an eosinophilia. However, in strong responder NIH mice leucocyte counts returned to normal more rapidly than in other strains (by day 28). In contrast, in weak responder C57BL/10 mice the leucocyte counts whilst falling significantly relative to day 7 did not return to normal within the experimental period. Mice infected with irradiated larvae did not experience as high a leucocytosis as did mice given an identical number of normal larvae. The peak lymphocytosis, neutrophilia and monocytosis were all lower. The removal of adult worms from infected animals by treatment with pyrantel on days 9,11,13 and 16, also significantly altered the pattern of leucocytosis. The neutrophilia which was evident on day 7 returned rapidly to normal, whereas in mice which had retained their worms a peak neutrophilia was observed on day 14. These haematological changes were discussed and related to the failure of hostprotective immunity to operate effectively during the early stages of a primary infection with N. dubius.

Observations on the gross changes in the secondary lymphoid organs of mice infected with Nematospiroides dubius

“…The animals used in all the experiments reported here were part of a larger study in which the hacmatological changes were also studied. The results of this work have been published elsewhere (ALI et al, 1985). The mice were killed with chloroform, weighed and were bled out by cardiac puncture.…”

“…Despite the host's inability to remove adult worms during this period, their presence in the intestine docs not go unrecognized. Thus the initial stages of a primary infection arc associated with pronounced hacmatological changes (BAKER, 1962;CYPESS, 1972;ALI et al, 1985) and with increased immunological activity as reflected in elevated levels of circulating parasite specific antibody (DOBSON, 1982;DOBSON & CAYZER, 1982;PRITCHARD, et al 1983) and in cellular proliferation within the secondary lymphoid organs (Liu, 1965;ALI, 1983). The mcscntcric lymph nodes and the spleen increase rapidly in size following a primary infection.…”

Immunological relationships during primary infection withHeligmosomoides polygyrus: Th2 cytokines and primary response phenotype

“…The murine trichostrongylid gastrointestinal (GI) nematode Heligmosomoides polygyrus causes chronic infections in most mouse strains, in some cases lasting for over 30 weeks in duration (Robinson et al 1989) and, in contrast to other GI nematodes such as Trichinella spiralis and Nippostrongylus brasiliensis, primary infections are not accompanied by intense mastocytosis (Dehlawi, Wakelin & Behnke, 1987), although other markers of the Th2 response are evident (e.g. IgE - Urban et al (1991); eosinophilia - Cypess (1972); Ali, Behnke & Manger (1985); parasite specific IgGl - Wahid & Behnke (1993a)). The low intensity mastocytosis and chronic survival of adult worms have both been attributed to the immunomodulatory activities of adult worms (Dobson & Cayzer, 1982;Behnke, 1987;Dehlawi & Wakelin, 1988), which have been shown to downregulate the potential of M L N cells to secrete IL-9 and IL-10 following stimulation by Concanavalin A (Con A) in vitro (Behnke et al 1993).…”

Effect of genetic variation on induced neutrophilia in mice

“…Although data showing genetically determined variation in neutrophil numbers exist for rats (22) and cattle (12), most experimental evidence is available for mice. Strain-dependent variation in the ability to mount neutrophil responses to a range of stimuli has been documented for a variety of mouse strains (1,5,6,8,20,21). Similarly, strain-related differences in the accumulation of neutrophils in the peritoneal cavity have been observed following injection of sterile irritants (8,20).…”