Hematological Characteristics of Rats Spontaneously Developing Eosinophilia.

Abstract

Hematological and genetic characteristics of newly found eosinophilic rats were studied. Hematologically, high blood eosinophil counts started at 6 weeks of age. Almost all 10-week-old rats had eosinophilia with individual counts above 500/µl and 5 to 100 times the normal level. Proliferating eosinophils had normal morphology. An increase in lymphocyte counts was observed at 5 weeks of age, one week earlier than the onset of eosinophilosis. In bone marrow, proliferation of eosinophils was also observed at 8 weeks of age and thereafter progressed, suggesting a role in the pathogenesis of eosinophilia in this rat. The results of genetic cross experiments revealed the disease to be hereditary. The spontaneously eosinophilic rat therefore warrants attention as a model for studying the underlying mechanisms of human and animal eosinophilia.

The spectrum of eosinophilic infiltration of the cecum and its relationship to other disorders of multiple granulomas and arteritis in Sprague-Dawlay rat

“…Specific infection leading to an increase in eosinophils was doubtful because no evidence of larval or adult parasites and no significant microorganisms were found histopathologically. Furthermore, this animal was maintained under SPF conditions and was also free from Aspergillus funmigatus infection which is known to cause eosinophilia (Matsumoto et al, 2000). Although we could not reveal mast cells with Giemsa stain, we were unable to completely rule out an allergic etiology, because we were unable to evaluate serum immunoglobulin E concentration.…”

“…In certain disease states, eosinophils can selectively accumulate in peripheral blood or any tissue in the body. Matsumoto et al (2000) reported that the mean normal count of blood eosinophils is 80 cells/μl in rats. In the rat in this case, the eosinophil count (107 cells/μl) was higher than the mean value of the other nine male rats of its control cohort, and also higher than the number reported by Matsumoto.…”

“…An accumulation of eosinophils occurs in several important disorders, such as allergic and parasitic disease, some malignant diseases, immunodeficiency diseases, and in idiopathic HES (Matsumoto et al, 2000;Rothenberg, 1998;Weller, 1991). In certain disease states, eosinophils can selectively accumulate in peripheral blood or any tissue in the body.…”

“…Eosinophils are increased in reactive diseases such as allergic and parasitic diseases, some malignant diseases, immunodeficiency diseases, and in idiopathic hypereosinophilic syndrome (HES) (Matsumoto et al, 2000;Gleich and Adolphson, 1986).…”

A Third Locus for Eosinophilia on Chromosome 1 of the MES Rats

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Abstract: Matsumoto Eosinophilia Shinshu (MES) is a rat strain that spontaneously develops eosinophilia and eosinophil-related inflammatory lesions in many organsThe etiology of the majority of idiopathic HES cases and the mechanisms of eosinophilopoiesis remain poorly understood.Matsumoto Eosinophilia Shinshu (MES) is a rat strain that develops eosinophilia spontaneously [3][4][5][6]8]. In these rats a marked increase in peripheral blood eosinophils (>500/µl) occurs at about 9 weeks of age, with eosinophilia progressing with age until the number of eosinophils eventually exceeds the level that is characteristic of human hypereosinophilia (>1,500/µl).

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