Cell Therapy in Veterinary Medicine as a Proof-of-Concept for Human Therapies: Perspectives From the North American Veterinary Regenerative Medicine Association

In the past decade, the potential to translate scientific discoveries in the area of regenerative therapeutics in veterinary species to novel, effective human therapies has gained interest from the scientific and public domains. Translational research using a One Health approach provides a fundamental link between basic biomedical research and medical clinical practice, with the goal of developing strategies for curing or preventing disease and ameliorating pain and suffering in companion animals and humans alike. Veterinary clinical trials in client-owned companion animals affected with naturally occurring, spontaneous disease can inform human clinical trials and significantly improve their outcomes. Innovative cell therapies are an area of rapid development that can benefit from non-traditional and clinically relevant animal models of disease. This manuscript outlines cell types and therapeutic applications that are currently being investigated in companion animals that are affected by naturally occurring diseases. We further discuss how such investigations impact translational efforts into the human medical field, including a critical evaluation of their benefits and shortcomings. Here, leaders in the field of veterinary regenerative medicine argue that experience gained through the use of cell therapies in companion animals with naturally occurring diseases represent a unique and under-utilized resource that could serve as a critical bridge between laboratory/preclinical models and successful human clinical trials through a One-Health approach

Type III collagen modulates fracture callus bone formation and early remodeling

Type III collagen (Col3) has been proposed to play a key role in tissue repair based upon its temporospatial expression during the healing process of many tissues, including bone. Given our previous finding that Col3 regulates the quality of cutaneous repair, as well as our recent data supporting its role in regulating osteoblast differentiation and trabecular bone quantity, we hypothesized that mice with diminished Col3 expression would exhibit altered long‐bone fracture healing. To determine the role of Col3 in bone repair, young adult wild‐type (Col3+/+) and haploinsufficent (Col3+/−) mice underwent bilateral tibial fractures. Healing was assessed 7, 14, 21, and 28 days following fracture utilizing microcomputed tomography (microCT), immunohistochemistry, and histomorphometry. MicroCT analysis revealed a small but significant increase in bone volume fraction in Col3+/− mice at day 21. However, histological analysis revealed that Col3+/− mice have less bone within the callus at days 21 and 28, which is consistent with the established role for Col3 in osteogenesis. Finally, a reduction in fracture callus osteoclastic activity in Col3+/− mice suggests Col3 also modulates callus remodeling. Although Col3 haploinsufficiency affected biological aspects of bone repair, it did not affect the regain of mechanical function in the young mice that were evaluated in this study. These findings provide evidence for a modulatory role for Col3 in fracture repair and support further investigations into its role in impaired bone healing. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:675–684, 2015.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111249/1/jor22838.pd

Therapeutic Neonatal Hepatic Gene Therapy in Mucopolysaccharidosis VII Dogs

Dogs with mucopolysaccharidosis VII (MPS VII) were injected intravenously at 2–3 days of age with a retroviral vector (RV) expressing canine β-glucuronidase (cGUSB). Five animals received RV alone, and two dogs received hepatocyte growth factor (HGF) before RV in an attempt to increase transduction efficiency. Transduced hepatocytes expanded clonally during normal liver growth and secreted enzyme with mannose 6-phosphate. Serum GUSB activity was stable for up to 14 months at normal levels for the RV-treated dogs, and for 17 months at 67-fold normal for the HGF/RV-treated dog. GUSB activity in other organs was 1.5–60% of normal at 6 months for two RV-treated dogs, which was likely because of uptake of enzyme from blood by the mannose 6-phosphate receptor. The body weights of untreated MPS VII dogs are 50% of normal at 6 months. MPS VII dogs cannot walk or stand after 6 months, and progressively develop eye and heart disease. RV- and HGF/RV-treated MPS VII dogs achieved 87% and 84% of normal body weight, respectively. Treated animals could run at all times of evaluation for 6–17 months because of improvements in bone and joint abnormalities, and had little or no corneal clouding and no mitral valve thickening. Despite higher GUSB expression, the clinical improvements in the HGF/RV-treated dog were similar to those in the RV-treated animals. This is the first successful application of gene therapy in preventing the clinical manifestations of a lysosomal storage disease in a large animal

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Skin-resident CD4⁺ T cells protect against <i>Leishmania major</i> by recruiting and activating inflammatory monocytes

<div><p>Tissue-resident memory T cells are required for establishing protective immunity against a variety of different pathogens, although the mechanisms mediating protection by CD4⁺ resident memory T cells are still being defined. In this study we addressed this issue with a population of protective skin-resident, IFNγ-producing CD4⁺ memory T cells generated following <i>Leishmania major</i> infection. We previously found that resident memory T cells recruit circulating effector T cells to enhance immunity. Here we show that resident memory CD4⁺ T cells mediate the delayed-hypersensitivity response observed in immune mice and provide protection without circulating T cells. This protection occurs rapidly after challenge, and requires the recruitment and activation of inflammatory monocytes, which limit parasites by production of both reactive oxygen species and nitric oxide. Overall, these data highlight a novel role for tissue-resident memory cells in recruiting and activating inflammatory monocytes, and underscore the central role that skin-resident T cells play in immunity to cutaneous leishmaniasis.</p></div

Utilization of Bone Morphogenetic Protein Receptors during Chondrocyte Maturation.

Cartilage from the upper, cephalic portion of embryonic chick sternums undergoes hypertrophy, while the lower, caudal portion of the sternum remains as cartilage. Bone morphogenetic proteins (BMPs) induce type X collagen (colX) in cultured upper but not lower sternal chondrocytes (LSCs). We have examined the utilization of BMP receptors (BMPRs) by upper sternal chondrocytes (USCs) and LSCs both by analyzing receptor expression and by overexpressing mutant BMPRs. Reverse-transcription polymerase chain reaction (RT-PCR) analyses indicate that both upper and lower chondrocytes produce messenger RNA (mRNA) for all three receptors: BMPR type IA (BMPR-IA), BMPR type IB (BMPR-IB), and BMPR type II (BMPR-II). Infection of USC with retroviral vectors expressing constitutively active (CA) BMPRs showed that CA-BMPR-IB, like exogenous BMP-4, induced both colX mRNA and elevated alkaline phosphatase (AP), while CA-BMPR-IA was markedly less potent. However, expression of activated receptors in LSC cultures resulted in only minimal induction of hypertrophic markers. Consistent with the results seen for CA receptors, dominant negative (DN) BMPR-IB blocked BMP-induced hypertrophy in USCs more effectively than DN-BMPR-IA. These results imply that the major BMPR required for BMP induction of chondrocyte hypertrophy is BMPR-IB, and that difference between permanent and prehypertrophic chondrocytes is not caused by absence of receptors required for BMP signaling

Circulating memory T cells are not required to control low dose <i>L</i>. <i>major</i> infection.

<p>A) Naive and immune mice were challenged in the ear with 10³ parasites and DTH was monitored over 72 hrs. B) Proportions of total CD45⁺ population in naive and immune ears 72 hrs after low dose challenge. C) Representative histogram showing frequency of MHCII cells in naive (black line) and immune (gray line) mice 72 hrs after low dose challenge. Data shown are from one experiment of two (n = 3 mice per group). D) Naive and immune flank skin were grafted side-by-side onto naive WT or RAG^-/- mice, then each graft was challenged with 10³ dsRed <i>L</i>. <i>major</i>. E) Parasite burden at 4 weeks was compared between intact naive and immune mice as well as naive and immune grafts on WT recipients. Data shown are from one experiment representative of two (n = 5 or 9 mice per group). F) Parasite burden at 4 weeks was compared between naive and immune grafts on WT or RAG^-/- recipients. Data shown are combined from two experiments (n = 5 mice per group). P < 0.05 = *; P < 0.01 = **; P < 0.001 = ***.</p

Early protection is not enhanced by circulating memory T cells.

<p>A) Naive, immune, and immune mice treated with FTY-720 or αCXCR3 were challenged intradermally in the ear with 2x10⁶ dsRed <i>L</i>. <i>major</i>. B) DTH response was monitored over the course of 3 days. C, D) Parasite burden (C) and the number of Ly6C⁺ monocytes in the infection site (D) was determined at 72 hrs. Data shown are from one experiment representative of two (n = 3 mice per group). E) Naive, immune, naive parabiotic, and immune parabiotic mice were challenged intradermally in the ear with 2x10⁶ dsRed <i>L</i>. <i>major</i>. F) DTH response was monitored over the course of 3 days. G, H) Parasite burden (G) and the number of Ly6C⁺ monocytes in the infection site (H) was determined at 72 hrs. Data shown are from one experiment representative of two (n = 3 mice per group). P < 0.05 = *; P < 0.01 = **; P < 0.001 = ***.</p