F. Fiorito

A new clinical approach: Use of blood-derived stem cells (BDSCs) for superficial digital flexor tendon injuries in horses

AIMS In this study, we present an innovative therapy using stem cells that were obtained from the peripheral blood of racehorses affected by uninduced superficial digital flexor tendon (SDFT) injuries. MAIN METHODS Blood-derived stem cells (BDSCs) were generated from the blood samples of three horses in the presence of macrophage colony-stimulating factor (M-CSF). The racehorses received a single autologous BDSC treatment, which resulted in the successful repair of the tendons injuries. KEY FINDINGS The results demonstrated that the BDSCs injection into the damaged tendon stimulated the regeneration of normal tissue. Furthermore, a relationship may exist between the speed and the quality of new tissue formation and the welfare and management of the treated animals. SIGNIFICANCE This study demonstrates that stem cell technology offers new tools for tissue repair that in many cases is considered incurable, and provides additional evidence that BDScs injections increase the speed and quality of the regeneration process in different animal tissues.

2,3,7,8-Tetrachlorodibenzo-p-dioxin increases Bovine Herpesvirus type-1 (BHV-1) replication in Madin-Darby Bovine Kidney (MDBK) cells in vitro.

Dioxin—2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) is a common environmental toxin of current interest. In the last years, higher levels of TCDD than those permitted in UE [European Commission. 2002. European Commission Recommendation 2002/201/CE. Official Gazette, L 67/69] were detected in milk samples from cow, water buffalo, goat, and sheep raised on some areas of Campania Region (South Italy). Dioxin often causes immunosuppression and might render the animal liable to viral infections. In addition, viral infections are able to alter the pattern of dioxin distribution in different organs of the exposed animals. Bovine Herpesvirus type‐1 (BHV‐1) is a widespread pathogen, which causes infectious rhinotracheitis and infectious pustular vulvovaginitis in cattle. Herein, we have studied the effects of TCDD and BHV‐1 infection, in Madin‐Darby Bovine Kidney (MDBK) cells, alone as well as in association, so as cellular proliferation, apoptosis, and virus replication. We have observed an increase in cell viability of confluent monolayers at low TCDD concentrations. TCDD treated cells demonstrated increased viability compared to controls as evaluated by MTT test. TCDD exposure increased cell proliferation but induced no changes on apoptosis. Cells exposed to TCDD along with BHV‐1 showed a dose‐dependent increase in cytopathy, represented by ample syncytia formation with the elimination of the cellular sheets and increased viral titer. These results suggest that TCDD increases viral replication in MDBK cells while BHV‐1 further decreases viability of TCDD exposed cells. Since very low concentrations (0.01 pg/ml) are sufficient to augment BHV‐1 titer, TCDD may contribute to reactivate BHV‐1 from latency, leading to recurrent disease and increase virus transmission. J. Cell. Biochem. 103: 221–233, 2008.

In vitro growth versus inhibition of growth of Malassezia pachydermatis in the presence of the antibacterial drug gentamicin.

Malassezia pachydermatis is part of the normal cutaneous microbiota of most warm-blooded vertebrates and is associated with otitis externa and seborrhoeic dermatitis in dogs and cats. In this study, we evaluated the growth capacity of nine M. pachydermatis strains on Sabouraud medium in the presence of a high concentration of gentamicin. Strains of M. pachydermatis cultured on Sabouraud medium in the presence of 50 and 100 µg gentamicin ml(-1) displayed different growth patterns such as growth or lack of growth. We hypothesized that this difference in growth of M. pachydermatis strains was correlated with the different genotypes of the strains. Random amplification of polymorphic DNA (RAPD) was applied for genetic typing of M. pachydermatis isolates, derived from the external ears of house pet cats suffering from otitis externa. The M. pachydermatis strains were cultured on commercial or home-made Sabouraud medium supplemented or not with gentamicin. RAPD analysis demonstrated a genetic heterogeneity between each strain. In particular, five out of nine strains tested were able to form colonies in the presence of gentamicin. However, a correlation between M. pachydermatis genotype and growth capacity in the presence of gentamicin was not widely demonstrated.