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Pulmonary function tests (PFTs) routinely implemented in clinics are the first step in the diagnosis of idiopathic pulmonary fibrosis. Evaluation of PFTs in the mouse model of pulmonary fibrosis accompanied by histological readouts may improve the clinical predictability of new therapeutic candidates. Forced vital capacity (FVC) is considered the most predictive of restrictive pulmonary disorders. This study aimed to test the improvement of PFT in mice lung fibrosis induced by treatment with an approved substance nintedanib, considered the gold standard. The hypothesis that treatment in animal models will demonstrate similar effects as in humans in the most relevant clinical outcomes was tested. Two experimental designs were enrolled in this study, a preventive regimen, with treatment initiation from the day of the challenge; and a therapeutic regimen, starting on day 7 postchallenge when fibrotic changes are present in the lungs. Experiments were terminated at two different time points, at 14 and 21 days postchallenge. C57BL/6 mice were administered with bleomycin (BLM) intranasally and treated with nintedanib from day 0 to day 14 or from day 7 until day 21. Fourteen or 21 days after the BLM challenge, PFTs were assessed using the in vivo invasive lung function measurement system Buxco® Pulmonary Function Test (PFT) (DSI™, New Brighton, USA). Histological evaluation was performed as a modified Ashcroft score. The bleomycin challenge induced a significant decrease of FVC in both experiments. However, nintedanib treatment given in both regimens significantly improved lung functionality. These findings were confirmed with histological analysis of the Ashcroft scoring system, modified by Matsuse. In conclusion, a good correlation between functional test parameters and the clinical effect of nintedanib was shown in both experiments: the preventive regimen was sampled 14 days post-challenge and the therapeutic regimen 21 days post-challenge. Based on these findings, the implementation of PFTs could be a good platform to increase the translational value of the model and potential new treatments.

Infectious haemolytic anaemia (IHA) in dogs share similar clinical signs including fever, lethargy, icterus, paleness of mucous membranes and splenomegaly. Postmortal findings are similar and, without additional diagnostic methods, an accurate aetiological diagnosis is difficult to achieve. In order to investigate causes of lethal IHA in Croatian dogs, we performed a retrospective study on archived formalin-fixed, paraffin-embedded tissue blocks (FFPEB) from dogs that died due to haemolytic crisis, using microscopic and molecular diagnostic tools to determine the aetiological cause of disease. Molecular analysis was performed on kidney, lung, myocardium and spleen on FFPEB from all dogs. The originally stated aetiological diagnosis of B. canis or leptospirosis was confirmed in only 53% of the dogs. PCR and sequencing revealed that, in addition to the expected pathogens, B. canis and Leptospira interrogans, the presence of previously undiagnosed "new" pathogens causing anaemia including Candidatus Neoehrlichia mikurensis and Anaplasma phagocytophilum. Furthermore, Theileria capreoli was detected for the first time in a dog with postmortal descriptions of lesions. Intensive extravascular hemolysis was noticeable as jaundice of the mucosa, subcutis and fat tissue, green or yellow discoloration of renal parenchyma caused by bilirubin excretion in the renal tubules and bile accumulation within the liver in 90% of the dogs. This work highlights the value of molecular diagnostics to complement traditional ante-mortem and post-mortem diagnostic protocols for the aetiological diagnosis of pathogens associated with IHA.

Pulmonary function tests (PFT’s) routinely implemented in clinics are the first step in the diagnosis of idiopathic pulmonary fibrosis. Evaluation of PFT’s in the mouse model of pulmonary fibrosis accompanied by histological readouts may improve clinical predictability of new therapeutic candidates. Forced expiration (FE) parameters are considered as the most predictive for restrictive pulmonary disorders. The aim of the study was to estimate the translational value of the PFT technique in the established mouse model by evaluating the effects of two approved therapies, pirfenidone and nintedanib. C57BL/6 mice were administered with bleomycin (BLM) intranasally and treated with pirfenidone or nintedanib from day 0 to day 14. Fourteen days after BLM challenge, PFT’s were assessed by using in vivo invasive lung function measurements. Histological evaluation was performed as modified Ashcroft score and digital analysis of de novo collagen deposition (CO1A1) and alpha-smooth muscle actin (αSMA) expression. Bleomycin challenge induced a significant decrease of forced vital capacity (FVC) and forced expiratory volume (FEV). Nintedanib treatment induced significant improvement of FE parameters, specifically 30% improvement of FVC and FEV100 in comparison to the vehicle control. Pirfenidone treatment showed no effect. These findings were confirmed with histological analysis. In conclusion, a good correlation of functional test results and clinical effect of nintedanib and pirfenidone was shown. Based on our findings, implementation of PFT could be a good platform to increase the translational value of the model.