Clinical alterations and mRNA levels of IL-4 and IL-5 in bronchoalveolar cells of horses with transient pulmonary eosinophilia

The aim of this study was to assess clinical signs and altered pulmonary cell expression of cytokines related to eosinophil kinetics in horses with pulmonary eosinophilia. Pulmonary eosinophilia was detected by bronchoalveolar lavage (BAL) in a group of standardbreds in training. Horses had detailed clinical examination, bronchoscopy, endobronchial biopsy and BAL on three occasions at approximately 6 month intervals. During the second sampling period BAL eosinophils were significantly elevated (p>0.010), with five horses having from 5% to 37% eosinophils in BAL. Neither detailed clinical examination parameters nor gene expression of IL-4 and IL-5 mRNA (real-time-PCR) were associated with BAL eosinophilia. Pulmonary eosinophilia abated without treatment apart from deworming. It appears that pronounced lung eosinophilia in horses can be transient, abate without specific treatment, and in this instance, lack correlation to upregulation of expression of either IL-4 or IL-5.     

Systemic and eosinophilic lesions in rats with spontaneous eosinophilia (mes rats)

The mes rat is from an inbred mutant colony of rats with spontaneous eosinophilia. In order to investigate the pathogenesis of the mes rat, the histopathology and hematology for 76 mes rats were examined at several weeks of age. Tissue eosinophilia developed at 8 weeks of age when the blood eosinophil was 500 cells per microliter or more. Subsequently, eosinophilia progressed with age, and splenic eosinophilopoiesis and erythropoiesis appeared simultaneously. Many inflammatory lesions were induced after 10 weeks of age when the blood eosinophils became 1,000 cells per microliter or more. Gastroenteritis and mesenteric lymphadenitis were seen in 44 of 47 (94%) and 31 of 47 (66%) rats, respectively, after 10 weeks of age. Aortitis that deteriorated with age was found in 19 of 39 (49%) rats after 12 weeks of age. Hepatic fibrosis was found in four rats that exhibited severe eosinophilia and anemia. These results are comparable to the features of a hypereosinophilic syndrome in humans and other animals.     

Nuclear lobe index in avian eosinophilia

The nuclear lobe index was calculated for eosinophils from adult fowl, ducks and quail with spontaneous or experimentally induced eosinophilia. Appropriate control birds were also examined. The nuclear lobe index in normal fowl was 1.95 compared with 1.91 in birds with eosinophilia. Although these results (in the fowl) are almost identical, further analysis revealed a distinct 'shift to the right' in those birds with counts greater than 20 per cent eosinophils (P less than 0.01). The normal nuclear lobe index in ducks was 2.68 compared with 2.60 in those with eosinophilia and thus no 'shift' was recognised. The quail, on the other hand, demonstrated a slight 'shift to the left' in which the normal nuclear lobe index was 2.46 compared with 2.20 lobes per cell in eosinophilic quail.     

Eosinophil relationship in gut anaphylaxis during experimental ancylostomosis

Changes induced in the circulating and intestinal eosinophil levels and worm load were studied in female Swiss albino mice infected with multiple doses of Ancylostoma caninum larvae. There was a significant rise of both circulating and intestinal eosinophils in all the infected animals when compared with controls. In all the experimental groups of animals, peak eosinophilia was observed during the third week of post-infection and sustained upto 30th day with slight alterations. These studies indicated that eosinophilia will be induced due to anaphylactic reactions in the gut and eosinophilia in multiple infections is an anamnestic response.     

Pulmonary infiltrates with eosinophilia

A seven-month-old collie and a four-year-old Jack Russell terrier were presented with coughing and dyspnoea of varying duration. A peripheral and pulmonary eosinophilia was detected in both dogs. After ruling out heartworm disease, lungworms, fungal pneumonia and drug reactions, a diagnosis of pulmonary infiltrates with eosinophilia was made. Dramatic relief of clinical signs, radiographic infiltrate and peripheral eosinophilia occurred after administration of glucocorticoids.     

Pulmonary eosinophilia and granulomatous pulmonary arteritis induced in rats by intravenous Sephadex.

Airway eosinophilia has been proposed as a major pathogenetic event in bronchial asthma and airway hyperresponsiveness. Intravenous injection of Sephadex G200 in rats induces pulmonary and blood eosinophilia and alters pulmonary responsiveness to 5-hydroxytryptamine. To characterize the early pulmonary inflammatory responses following Sephadex administration, and to determine the timing of the onset of pulmonary eosinophilia relative to blood eosinophilia, Sprague-Dawley rats were injected intravenously with Sephadex G200 beads. Lungs and other tissues were examined by light and transmission electron microscopy at 4, 12, 24, 48, 72, and 96 hours after injection. Blood eosinophil counts were determined at 0, 24, and 96 hours after injection. Sephadex beads were trapped initially in small caliber muscular pulmonary arteries associated with terminal bronchioles and in intra-acinar locations. There was marked infiltration of eosinophils and macrophages around the beads and into arterial walls and edematous periarterial and peribronchiolar connective tissue as early as 4 hours after injection. Periarterial-peribronchiolar eosinophil aggregates peaked in density at 24 and 48 hours. Macrophages and multinucleated cells dominated the inflammatory cell responses in arteries immediately surrounding partially degraded Sephadex beads from 24 to 96 hours. Bone marrow eosinophilopoiesis and blood eosinophilia were not detected until 96 hours. We conclude that Sephadex induces pulmonary eosinophilia prior to blood eosinophilia and suggest that Sephadex may induce pulmonary release of one or more eosinophil chemotactic substance(s). This model may prove useful in the study of factors that influence eosinophil migration into the lung in various disease states.     

Canine eosinophilic bronchopneumopathy.

Eosinophilic bronchopneumopathy (EBP) is a disease characterized by eosinophilic infiltration of the lung and bronchial mucosa, as demonstrated by examination of bronchoalveolar lavage fluid cytologic preparations or histologic examination of the bronchial mucosa. Although the precise cause of EBP is unknown, a hypersensitivity to aeroallergens is suspected. The diagnosis relies on typical history and clinical signs, demonstration of bronchopulmonary eosinophilia by cytology or histopathologic examination, and exclusion of known causes of lower airway eosinophilia. Most dogs display an excellent response to oral corticosteroid therapy; however, side effects of this treatment can be limiting. New therapeutic approaches are being studied, including the use of aerosol therapy, cyclosporine, or drugs interfering with T helper 2 immune response.     

Clinicopathological findings and results of bone marrow aspiration in dogs with cutaneous mast cell tumours: 157 cases (1999–2002)*

Bone marrow aspiration for routine staging of canine cutaneous mast cell tumour is not consistently performed, and the overall incidence of bone marrow infiltration and predictive value of the complete blood count (CBC) is unknown. This study evaluated a series of 157 dogs presented for cutaneous mast cell tumours in which a CBC and bone marrow aspiration were performed. The incidence of bone marrow infiltration at initial staging was low at 2.8%, and 4.5% overall. Factors significantly associated with bone marrow infiltration included increased age, leucocytosis, anaemia, neutrophilia, monocytosis, eosinophilia, thrombocytopenia, being purebred and staging at the time of recurrent or progressive disease. Our study suggests that a bone marrow sample is not indicated for routine staging but maybe indicated for those dogs with mast cell tumours having either an abnormal haemogram (neutrophilia, monocytosis, eosinophilia, basophilia, anaemia and thrombocytopenia) or presenting for tumour regrowth, progression or new occurrence.     

Changes to plasminogen activators and matrix metalloproteinase-9 in dogs with toxocarosis

The relationship between proteolytic enzymes and hematological response to infection was studied in five 1-month-old dogs inoculated experimentally with 2000 eggs of Toxocara canis. Moderate leukocytosis and marked eosinophilia occurred 14 days post-infection with T. canis. Plasminogen activators (PAs) and matrix metalloproteinase-9 (MMP-9) activity in serum was significantly different in dogs infected with T. canis, compared with controls. Urokinase-type PA (uPA) activity was positively correlated with eosinophilia, and tissue-type PA (tPA) and MMP-9 activity was negatively correlated with eosinophilia. However, there was no correlation between inflammation and MMP-2. The use of uPA, tPA or MMP-9 proteolytic enzymes as laboratory reference markers for toxocarosis requires further study.     

Successful treatment of hypereosinophilic syndrome in a dog

An 11-year-old crossbred dog was presented with a history of episodic vomiting, diarrhoea, abdominal discomfort and coughing. These signs had been present for several years. Marked peripheral eosinophilia (10.3 x 10(9)/L) was found. No underlying cause of reactive eosinophilia was apparent. Bone marrow aspiration biopsy showed hyperplasia of the eosinophilic cell line, with some increase in immaturity, although all cells were morphologically normal. There were numerous eosinophils in bronchial wash fluid and eosinophilic infiltrates were evident in biopsies of pancreas, liver, small intestine and colon but not stomach. Hypereosinophilic syndrome was diagnosed. The dog responded well to twice daily treatment with hydroxyurea and prednisolone. Clinical signs are well-controlled 16 months later.     

Relationships among peripheral eosinophilia, eosinophil peroxidase activity, interleukin-5 concentration and faecal nematode egg count during natural, mixed gastrointestinal nematode infection

A longitudinal study of sheep, naturally infected with gastrointestinal helminths, was carried out to quantify the relationships among eosinophilia, eosinophil peroxidase activity, interleukin-5 level and faecal egg counts. Faecal egg counts, peripheral eosinophilia and peroxidase activity per eosinophil were moderately repeatable but interleukin-5 concentrations had a remarkably high repeatability. Animals with higher concentrations of interleukin-5 had greater peripheral eosinophilia and those animals with higher numbers of eosinophils had lower faecal egg counts. These associations were statistically significant but quite weak. Variation in interleukin-5 levels does not appear to be responsible for most of the variation in eosinophil responses in outbred sheep.     

Atopic NC/Nga mice as a model for allergic asthma: cytokine profiles and eosinophil productivity of bone marrow

In previous study, NC/Nga mice with experimentally induced asthma showed severe eosinophilia. To explore the mechanism, profiles of representative cytokines interleukin (IL)-4, IL-5, and interferon (IFN)-gamma were examined in bronchoalveolar lavage fluid. The level of only IFN-gamma was lower in NC/Nga mice than control BALB/c mice. Furthermore, bone marrow cell culture system under the presence of eosinopoietic cytokines, which induce the differentiation of progenitor cells into mature eosinophils, showed that a larger number of eosinophils differentiated from NC/Nga mice derived bone marrow cells than from control BALB/c mice. These results may imply the possibility that severe eosinophilia in the NC/Nga mice are attributable to lower production of IFN-gamma and higher eosinophil productivity of bone marrow cells.     

Equine tracheobronchial lavage: comparison of lavage cytologic and pulmonary histopathologic findings

Differential cell counts were done on bronchial lavage specimens from 166 horses. Postmortem gross and histologic examinations were done to determine the pathologic diagnosis of the lungs from these horses. Ninety-two (55%) were normal, 18 (11%) had interstitial pneumonia, 13 (8%) had bronchopneumonia, 13 (8%) had focal eosinophilia, 11 (7%) had diffuse eosinophilia, 11 (7%) had chronic bronchitis, and 8 (5%) had suppurative bronchitis. Little relationship was found between cellular features of the lavage specimens and the pathologic status of the lungs of individual horses.     

Idiopathic hypereosinophilic syndrome in 3 Rottweilers

Three Rottweilers with marked peripheral eosinophilia and infiltration of the liver, spleen, lungs, and bone marrow with eosinophils were diagnosed with idiopathic hypereosinophilic syndrome (IHES). Mean serum immunoglobulin E concentrations were markedly high. On cytogenetic analysis, no evidence of karyotypic abnormalities was found in bone marrow aspirates. Despite an extensive search, no underlying cause for the eosinophilia could be identified. In this study, cytogenetic analysis and measurement of serum IgE concentrations were used to differentiate IHES and eosinophilic leukemia.     

Synovial fluid eosinophilia: a case report in a dog and review of the literature

The first known report of synovial fluid eosinophilia in a dog is described here. The occurrence of eosinophils in joint fluid is rare. Sporadic cases have been recorded in humans and most can be related to immunemediated reactions, both parasitic and non- parasitic. The dog in this case report had 20-52% eosinophils in multiple joints, as well as hemarthrosis and marked mononuclear cell reactivity. An intense peripheral eosinophilia was demonstrated one week later. The associated lameness resolved with non-steroidal anti-inflammatory therapy. Lack of remarkable history or other clinical symptoms led to a diagnosis of idiopathic, eosinophilic, polyarthritis, likely immune-mediated.     

Immunoglobulin G4‐related disease in a dog

Immunoglobulin G4‐related disease (IgG4‐RD), which affects many organ systems, has been recognized as a distinct clinical entity in human medicine for just over a decade but has not been previously identified in dogs. In humans, IgG4‐RD is characterized by diffuse IgG4‐positive lymphoplasmacytic infiltrates that commonly lead to increased serum concentrations of IgG4 and IgE, peripheral eosinophilia, tumorous swellings that often include the parotid salivary glands, obliterative phlebitis, and extensive fibrosis. Herein we describe the diagnosis, clinical progression, and successful treatment of IgG4‐RD in an 8‐year‐old female spayed Husky mixed breed dog. Immunoglobulin G4‐related disease should be considered as a differential diagnosis for dogs with vague clinical signs, lymphoplasmacytic swellings, restricted polyclonal gammopathy, eosinophilia or some combination of these findings.     

The response of Nigerian West African Dwarf goats to experimental infections with Haemonchus contortus

One option for controlling haemonchosis in warm pastoral regions is improvement of resistance by selective breeding. Variation in acquired immunity to H. contortus and immunological correlates of infection were studied in West African Dwarf (WAD) goats. Following exposure to 5000 L3, 63 per cent of the inoculum established but 77 per cent of established worms were expelled by week 5. All infected animals were anaemic (day 14). When exposed to 2000L3, 36 per cent of the inoculum was still present (day 35) with no loss by day 49. Persisting primary infection worms survived a superimposed challenge (day 35), but their growth was slowed and resistance to challenge was significant. Most goats showed eosinophilia and parasite-specific IgG responses to primary infection, but only eosinophilia increased after challenge. No consistent associations were found between parasite burden and any immunological measures of infection, but parasite egg counts showed considerable variation. Overall, our results suggest that resistant genotypes exist among the WAD goat population.     

Hypereosinophilic syndrome in two cats

Two cats showing chronic vomiting, diarrhea and weight loss were found to have leukocytosis with marked eosinophilia. Both cats were diagnosed with hypereosinophilic syndrome by the findings of increased eosinophils and their precursors in the bone marrow, eosinophilic infiltration into multiple organs, and exclusion of other causes for eosinophilia. Although cytoreductive chemotherapy with hydroxycarbamide and prednisolone was performed, these two cats died 48 days and 91 days after the initial presentation.     

Diseases associated with pronounced eosinophilia: a study of 105 dogs in Sweden

Records of 105 dogs with pronounced eosinophilia (>2.2 X l0⁹ eosinophils/litre) were evaluated in a retrospective study to determine diseases associated with the abnormality in dogs in Sweden. Inflammatory disease in organs with large epithelial surfaces, such as the gut, lungs or skin, was found in 36 per cent of the dogs. A further one-quarter of the 105 cases were placed in the 'miscellaneous' category, which comprised various diseases found at low frequency. The most well defined diagnosis was pulmonary infiltrates with eosinophils in 12 per cent of the dogs. A further 11 per cent had parasitic disease caused by either sarcoptic mange or nasal mite. No atopic dog was found and rottweilers were over-represented in most disease groups. Pronounced eosinophilia, in many cases transient, seems to be associated with a variety of disorders in dogs. In the present study, rottweilers appeared to be more prone to a high eosinophil response than other breeds.     

Beneficial cross-protection of allergen-specific immunotherapy on airway eosinophilia using unrelated or a partial repertoire of allergen(s) implicated in experimental feline asthma

The study hypothesis was that in experimentally asthmatic cats rush immunotherapy (RIT) using allergens not completely matched with sensitizing allergen(s) would at least partially attenuate the asthmatic phenotype and modulate the aberrant immune response. In phase I, cats sensitized to Bermuda grass allergen (BGA), house dust mite allergen (HDMA) or placebo received BGA RIT. In phase II, cats dually sensitized to BGA and HDMA received RIT using BGA, HDMA or placebo. Efficacy of RIT was assessed using percentage bronchoalveolar lavage fluid (BALF) eosinophils. Additionally, a variety of immunologic assays were performed. Eosinophilic airway inflammation significantly decreased over time in asthmatic cats given RIT using sensitizing allergen or unrelated allergen (P<0.001). In dually sensitized cats, single allergen RIT but not placebo reduced airway eosinophilia (P=0.038). Differences in allergen-specific lymphocyte proliferation, in the number of IL-10 producing cells and in the percentage T regulatory cells were detected between asthmatic cats getting RIT and controls. Cross-protection manifested by reduced airway eosinophilia was noted in cats treated with RIT allergens which did not completely match allergen used in asthma induction. However, the mechanism of immunologic tolerance may differ when improperly matched allergens to the sensitizing allergens are used in RIT.