Abstract

Hmga2 inactivation suppresses the development of a melanoma phenotype in skin exposed to UVB light

Elizabeth S. Lavin, Leanne R. Donahue, Hyeongsun Moon, Luye An, Andrew C. White
College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA (Elizabeth Lavin), Department of Biomedical Sciences, Cornell University, Ithaca, NY 14853, USA

Hmga2 is an architectural chromatin-remodeling factor that is upregulated in many cancers, including melanoma. Previous findings suggest that Hmga2 inactivation may prevent ultraviolet B (UVB)-mediated melanoma development, potentially through changes in inflammatory infiltration. Using murine models, we investigate the role of Hmga2 in skin exposed to UVB radiation to characterize environmental changes in Hmga2 -/- skin that may inhibit early melanomagenesis. We demonstrate that moderate acanthosis occurs in wild type skin within three days following UVB exposure, and loss of Hmga2 significantly attenuates this phenotype. Specifically, time course experiments demonstrate that expansion of the basal Keratin 5 (K5) and suprabasal Keratin 10 (K10) epidermal populations are markedly reduced in Hmga2-/- skin. These findings delineate the role of Hmga2 in modifying the cutaneous microenvironment in response to UVB exposure and in early melanoma formation.

Research Grant: NIH Training Grant
Student Support: Veterinary Investigators Program, Cornell University College of Veterinary Medicine

This abstract was submitted by Elizabeth Lavin from Cornell University. Thanks, Elizabeth!

Stemness and the Post-Injection Response of the Equine Joint to MSC Injection

Jessica Xu, Texas A&M University

Cases/Abstracts, Honorable Mention

Jiajie Jessica Xu, Amanda-Jo Joswig, Ashlee Watts
Comparative Orthopedics and Regenerative Medicine Lab, College of Veterinary Medicine, Texas A&M University
Merial Veterinary Scholars Program and the College of Veterinary Medicine & Biomedical Sciences, Texas A&M University
Link Equine Research Endowment

Stemness and the Post-Injection Response of the Equine Joint to MSC Injection

A mesynchymal stem cell (MSC)’s ability to undergo trilineage differentiation into osteoblasts, adipocytes, and chondroblasts in vitro is one of the defining characteristics of MSC stemness. This quality allows MSCs to be used as a source of cells in tissue engineering and cell therapy. In addition to cellular differentiation, MSCs also play a role in modulating inflammatory responses by releasing anti-inflammatory factors during tissue repair. Though traditional stemness has been associated with effective tissue repair, the relationship between MSC stemness and immunomodulatory function is unknown. To study this, bone marrow derived MSCs were collected from 6 horses, and injected autologously. The same MSCs were also injected allogeneically into 6 separate horses. Joint fluid cytologic analysis was performed on injected joints to assess the inflammatory response. Stem cells from the donor horses were then cultured in vitro and tested for their ability to undergo trilineage differentiation using visual grading systems. By comparing MSC inflammatory response with stemness qualities, this study re-examines the criteria of what it means to be an effective stem cell. 

Surfactant protein D as a biomarker of bronchopneumonia in calves

Jennifer Storer, University of Tennessee

Cases/Abstracts, Honorable Mention

Title: Surfactant protein D as a biomarker of bronchopneumonia in calves.

 
Bronchopneumonia in cattle is a costly disease caused by multiple pathogens. Mannheimia haemolytica is the most frequently isolated etiologic agent and induces tremendous inflammation through the production of a leukotoxin. Surfactant protein D is produced by type II pneumocytes and is tissue specific for the lungs. During alveolar inflammation these proteins are up-regulated and may be released into the blood. We hypothesized that these proteins could be detected in the serum and serve as biomarkers for alveolar membrane damage and overall pulmonary inflammation. This study used bronchoselective endoscopic inoculation of Mannheimia haemolytica or sterile saline of the right apical lung lobe in twelve 4 month old dairy calves. Six principal calves received 3-5 x 109 colony forming units of M. haemolytica in a 5mL suspension of phosphate-buffered saline, while 6 control calves received an equivalent volume of sterile phosphate buffered saline (PBS). Serum and bronchoalveolar lavage (BAL) samples were collected to analyze surfactant protein D with a bovine specific ELISA. Serum samples were collected daily for seven days, while BAL samples were collected on days 0, 1, 3, 5, and 7. Calves were additionally assigned a clinical illness score twice daily and a datalogger outfitted with accelerometers were placed on the left rear fetlock of each calf to assess behavioral changes. We hope the results of this study will provide information for the use of surfactant proteins in the diagnosis of BRD.

Amphibian Microbiomes as Indicators of Individual and Environmental Health

Sarah Leyman, The Ohio State University

Cases/Abstracts, Winner

AMPHIBIAN MICROBIOMES AS INDICATORS OF INDIVIDUAL AND ENVIRONMENTAL HEALTH

Sarah Leyman¹, Barbara Wolfe¹, Paula Mouser² 

¹The Ohio State University College of Veterinary Medicine, 1900 Coffey Road, Columbus, OH, USA

²The Ohio State University Department of Civil, Environmental and Geodectic Engineering, 2070 Neil Avenue, Columbus, OH, USA

Amphibians depend on their cutaneous microbial community as a first line of immune defense against disease. However, very few studies have been performed to characterize the bacterial genera found on the skin of different amphibian species and under different water quality conditions.  The goal of this study was to classify the bacterial genera present on the skin of two Lithobates species living in lakes of highly variant water characteristics on a reclaimed surface mine.  A second objective was to develop a baseline frog microbiome library on the site prior to shale gas exploration in order to monitor microbiome changes in association with environmental disturbance. Northern green frogs (Lithobates clamitans melanota) and American bullfrogs (Lithobates catesbeiana) were caught from 10 different lakes on the Wilds in Cumberland, OH.  Skin swabs were collected following a sterile saline solution rinse for bacterial characterization and to test for Batrachochytrium dendrobatiditis (Bd), the etiologic agent of amphibian chytridiomycosis.  Pharyngeal swabs were taken to test for ranavirus, another emerging disease of amphibians, and blood samples were collected to assess the heterophil-lymphocyte ratio as an indicator of stress. Water quality parameters were documented and water samples collected for chemical analysis at the time of frog capture for each site. The DNA was extracted from the bacterial swabs and sequenced using 454 pyro-sequencing.  At least one frog from each site tested was positive for Bd, but no frogs were positive for ranavirus.  Water quality among sites varied with regard to pH (4.10 to 8.66), conductivity (137.5 μS/cm to 3.51 mS/cm), ionic content, and dissolved organic carbon (0.13 mg/L to 11.7 mg/L).  Our study identified over 300 different genera of microbes representing 68 orders present on frogs on this site. Water quality parameters were found to be associated with differential microbial colonization and physiologic parameters.

*Click the thumbnail pictures below to see full size images*

Back arch posture in dairy cows: An indicator of early signs of lameness?

Entry, Abstracts
Carlie Gordon, Washington State University

Background:  Visual observation of an arched back in dairy cattle while they are standing and walking is one criterion for assessing lameness through locomotion scoring. However, observation of a back arch while cows are in stanchions is only variably associated with lameness. If the observation of back arch could be better defined, the sensitivity of this method might be improved. It was the purpose of this study to evaluate the degree of back arch that would differentiate lame from non-lame cows while in stanchions and assess if the back arch posture in the lock-up is a predictable observation for lameness. This picture is showing a cow in lock up with an arched (concave) back. The cow in this picture has a back arch of 168 °, a deviation of 12° from a flat back as indicated by the orange line across her back.

Methods: Locomotion scores were collected for all lactating Holstein cows on one farm. Cows with scores of two or greater were used for this study. Eighteen cows received a locomotion score of ≥ 3 and 55 cows received a locomotion score of ≤ 2. Digital photographs of these cows while in stanchions and from videos as they exited the milking parlor were taken. Images were analyzed for the degree of back arch, “deviation from flat”, where a flat back was considered 180°. In addition, cows in one pen were observed 5 successive times while stanchioned to evaluate time in lockup effects on the presence of a back arch.

Results: The angle of deviation from cows during lockup was not associated with locomotion score. However, there was a trend for cows that were determined to have a locomotion score of ≥ 3 to have back angles that deviated further from 180 °. From the successive observations, back-arch was not a consistent observation but the proportion of observation time a cow was observed with a back arch was significantly greater for lame cows vs. non lame cows. This picture is showing another cow in lockup. This cow has a straight back measuring 180 ° as indicated by the orange line across her back.

Conclusions: Our results indicate that the back arch observation, although inconsistently associated with locomotion scoring, could be used as a simple screening tool by veterinarians and dairy producers if frequent observations are made while the cows are stanchioned.

*Note: An organge paint stick was used to mark the withers and tail-head of each cow, pictures of each cow in lockup were then taken and at a later date a program called vistametrix was used to assess the the angle of each cow’s back