Regulatory T lymphocytes and selected cytokines in horses with mild to severe equine asthma and different inflammatory cytology profiles.

This study determined Tregs and inflammatory cytokines in BALF and peripheral blood (PB) of adult horses with mild and severe asthma and different BALF cytological inflammation profiles. Horses of diverse breeds with asthma (age range: 2-20 years, n = 24) were divided into groups according to the number of points obtained in a standardized clinical scoring system (mild-moderate equine asthma - MEA, severe equine asthma - SEA) and according to the inflammation type based on cytological finding. Plasma levels of IFN-γ, IL-4, IL-10, IL-17 and MMP-9 in the BALF were determined by ELISA. Tregs in the BALF and PB were detected by flow cytometry. Horses with SEA were older than horses with MEA and had higher concentrations of MMP-9 in the BALF (P < 0.05). The neutrophilic inflammation group was characterised by higher age, grade of clinical score, percentage of Tregs and MMP-9 concentration in the BALF compared to the mastocytic inflammation group (P < 0.05). Age positively correlated with neutrophils, grade of score, Tregs in the BALF and in the PB. The grade of score positively correlated with MMP-9. The percentage of Tregs in the BALF positively correlated with Tregs in the PB. Tregs in the BALF and PB positively correlated with neutrophils and MMP-9 in the BALF and with IFN-γ, IL-4 and IL-10 in the plasma. IFN-γ and IL-10 in the plasma positively correlated with the age. The results indicate that the evaluation of selected parameters in PB, the collection of which is less invasive than the collection of BALF, is of potential importance.

Lymphocyte immunophenotyping and concentration of MMP-9 in transudates and exudates in horses.

This study is the first to provide information on the lymphocyte subpopulations in peritoneal effusions in horses. Peritoneal transudates (n = 12), peritoneal exudates (n = 6) and a pleural exudate (n = 1) were analyzed. The total nucleated cell count (TNCC), total protein (TP) and matrix metalloproteinase-9 (MMP-9) concentration determined by ELISA were measured and routine cytological evaluation was performed. CD3, CD4, CD8 and CD21 positive cells were detected by flow cytometry. A higher percentage of neutrophils (P < 0.05) and higher MMP-9 (P < 0.01) levels were found in exudates. A higher percentage of macrophages (P < 0.05) and lymphocytes (P < 0.01) were found in transudates. CD4 + lymphocytes were the most common lymphocyte subpopulation in all samples. CD21 + lymphocytes were the least common in all samples. A large variability in the percentage of CD21 + lymphocytes was found in exudates. The percentage of CD21 + lymphocytes positively correlated with the level of total protein (r = 0.5704, P < 0.05). The correlation was even stronger in the group of exudates. The percentages of lymphocyte subpopulations did not correlate with the level of MMP-9 or with cytological findings. The level of MMP-9 positively correlated with the percentage of neutrophils (r = 0.4980, P < 0.05), the level of TP (r = 0.7855, P < 0.01) and TNCC (r = 0.6129, P < 0.01). A significantly higher level of MMP-9 was detected in euthanized horses than in horses that survived (P < 0.05). However, it was shown that the level of MMP-9 in the peritoneal fluid can change significantly in a short time. More studies on repeated abdominocentesis could contribute to elucidating the role of MMP-9 as a prognostic indicator.

Diagnosis of Aspergillosis in Horses.

Invasive pulmonary aspergillosis (IPA) may be a rare cause of granulomatous pneumonia in horses. The mortality of IPA is almost 100%; direct diagnostic tools in horses are needed. Bronchoalveolar lavage fluid (BALF) and serum samples were collected from 18 horses, including individuals suffering from IPA (n = 1), equine asthma (EA, n = 12), and 5 healthy controls. Serum samples were collected from another 6 healthy controls. Samples of BALF (n = 18) were analyzed for Aspergillus spp. DNA, fungal galactomannan (GM), ferricrocin (Fc), triacetylfusarinin C (TafC), and gliotoxin (Gtx). Analysis of 24 serum samples for (1,3)-ß-D-glucan (BDG) and GM was performed. Median serum BDG levels were 131 pg/mL in controls and 1142 pg/mL in IPA. Similar trends were observed in BALF samples for GM (Area under the Curve (AUC) = 0.941) and DNA (AUC = 0.941). The fungal secondary metabolite Gtx was detected in IPA BALF and lung tissue samples (86 ng/mL and 2.17 ng/mg, AUC = 1).

Newborn foal with atypical myopathy.

The case of atypical myopathy (AM) in newborn Haflinger foal with clinical signs of depression and weakness appearing 6 hours after birth resulting in recumbency 12 hours after birth is described. The foal's dam was diagnosed with AM in the 6th month of gestation based on clinical signs of a myopathy, elevated serum activity of creatine kinase, metabolomic analysis and the presence of methylenecyclopropyl acetyl carnitine (MCPA-carnitine) in the blood. At the time of delivery, the mare was grazing on a pasture near sycamore trees but was free of clinical signs of AM. Metabolomic analysis of the foal's blood revealed increased concentrations of acylcarnitines and MCPA-carnitine consistent with metabolic profiles of blood from AM affected horses. Two theories could explain this observation (a) hypoglycin A or its metabolites accumulated in the mare's placenta with consequent transfer to fetus or (b) these compounds were secreted into mare's milk.

Cytological and bacteriological evaluation of transendoscopic guttural pouch lavages in clinically healthy horses.

Thirty-eight guttural pouch lavages from 19 clinically healthy horses were collected transendoscopically. Cytological examination and bacteriological culture of the samples were carried out. All 38 lavages assessed for cytology contained less than five per cent neutrophils and could be termed as cytologically 'normal'. In none of the lavages did the neutrophil count vary between five and 25 per cent or exceed 25 per cent, which are the borderlines for being termed 'reactive' or 'pathological', respectively. Epithelial cells were the most commonly represented cell type in all lavages. Bacteriological culture was positive in 16 out of 38 lavages, but specific pathogenic bacteria were not cultivated in any of them, and only transient microflora was present. Although the relationship between the presence of specific bacteria, neutrophil count and total cell count could not be statistically evaluated due to the absence of 'reactive' and 'pathological' lavages, transendoscopic lavage appears to be a reliable method for obtaining a sample for bacteriological culture.