Exclusive expression of KANK4 promotes myofibroblast mobility in keloid tissues.

Keloids are characterized by abnormal wound healing with excessive accumulation of extracellular matrix. Myofibroblasts are the primary contributor to extracellular matrix secretion, playing an essential role in the wound healing process. However, the differences between myofibroblasts involved in keloid formation and normal wound healing remain unclear. To identify the specific characteristics of keloid myofibroblasts, we initially assessed the expression levels of well-established myofibroblast markers, α-smooth muscle actin (α-SMA) and transgelin (TAGLN), in scar and keloid tissues (n = 63 and 51, respectively). Although myofibroblasts were present in significant quantities in keloids and immature scars, they were absent in mature scars. Next, we conducted RNA sequencing using myofibroblast-rich areas from keloids and immature scars to investigate the difference in RNA expression profiles among myofibroblasts. Among significantly upregulated 112 genes, KN motif and ankyrin repeat domains 4 (KANK4) was identified as a specifically upregulated gene in keloids. Immunohistochemical analysis showed that KANK4 protein was expressed in myofibroblasts in keloid tissues; however, it was not expressed in any myofibroblasts in immature scar tissues. Overexpression of KANK4 enhanced cell mobility in keloid myofibroblasts. Our results suggest that the KANK4-mediated increase in myofibroblast mobility contributes to keloid pathogenesis.

＜Editors' Choice＞ Supernatant from activated omentum accelerates wound healing in diabetic mice wound model.

Diabetic wounds are considered one of the most frequent and severe complications of diabetes mellitus. Recently, the omentum has been used in diabetic wound healing because of its tissue repair properties. The activated omentum is richer in growth factors than the inactivated, thereby contributing to the wound healing process. To further investigate the effect of activated omentum conditioned medium (aOCM) on diabetic wound healing, we injected supernatant from aOCM, saline-OCM (sOCM), inactivated-OCM (iOCM), and medium (M) subcutaneously upon creation of a cutaneous wound healing model in diabetic mice. Wound area (%) was evaluated on days 0, 3, 5, 7, 9, 11, 14, 21, and 28 post-operation. At 9 and 28 d post-operation, skin tissue was harvested and assessed for gross observation, neovascularization, peripheral nerve fiber regeneration, and collagen deposition. We observed that aOCM enhanced the wound repair process, with significant acceleration of epidermal and collagen deposition in the surgical lesion on day 9. Additionally, aOCM displayed marked efficiency in neovascularization and peripheral nerve regeneration during wound healing. Thus, aOCM administration exerts a positive influence on the diabetic mouse model, which can be employed as a new therapy for diabetic wounds.

Acute Elution of TGFß2 Affects the Smooth Muscle Cells in a Compliance-Matched Vascular Graft.

Transforming growth factor beta 2 (TGFß2) is a pleiotropic growth factor that plays a vital role in smooth muscle cell (SMC) function. Our prior in vitro work has shown that SMC response can be modulated with TGFß2 stimulation in a dose dependent manner. In particular, we have shown that increasing concentrations of TGFß2 shift SMCs from a migratory to a synthetic behavior. In this work, electrospun compliance-matched and hypocompliant TGFß2-eluting tissue engineered vascular grafts (TEVGs) were implanted into Sprague Dawley rats for 5 days to observe SMC population and collagen production. TEVGs were fabricated using a combined computational and experimental approach that varied the ratio of gelatin:polycaprolactone to be either compliance matched or twice as stiff as rat aorta (hypocompliant). TGFß2 concentrations of 0, 10, 100 ng/mg were added to both graft types (n = 3 in each group) and imaged in vivo using ultrasound. Histological markers (SMC, macrophage, collagen, and elastin) were evaluated following explanation at 5 days. In vivo ultrasound showed that compliance-matched TEVGs became stiffer as TGFß2 increased (100 ng/mg TEVGs compared to rat aorta, p < 0.01), while all hypocompliant grafts remained stiffer than control rat aorta. In vivo velocity and diameter were also not significantly different than control vessels. The compliance-matched 10 ng/mg group had an elevated SMC signal (myosin heavy chain) compared to the 0 and 100 ng/mg grafts (p = 0.0009 and 0.0006). Compliance-matched TEVGs containing 100 ng/mg TGFß2 had an increase in collagen production (p < 0.01), general immune response (p < 0.05), and a decrease in SMC population to the 0 and 10 ng/mg groups. All hypocompliant groups were found to be similar, suggesting a lower rate of TGFß2 release in these TEVGs. Our results suggest that TGFß2 can modulate in vivo SMC phenotype over an acute implantation period, which is consistent with our prior in vitro work. To the author's knowledge, this is the first in vivo rat study that evaluates a TGFß2-eluting TEVG. Impact statement TGFß2 affects the SMCs in a vascular graft.

In-vivo assessment of a tissue engineered vascular graft computationally optimized for target vessel compliance.

Tissue engineered vascular grafts (TEVGs) have the ability to be tuned to match a target vessel's compliance, diameter, wall thickness, and thereby prevent compliance mismatch. In this work, TEVG compliance was manipulated by computationally tuning its layered composition or by manipulating a crosslinking agent (genipin). In particular, these three acelluluar TEVGs were compared: a compliance matched graft (CMgel - high gelatin content); a hypocompliant PCL graft (HYPOpcl - high polycaprolactone content); and a hypocompliant genipin graft (HYPOgen - equivalent composition as CMgel but hypocompliant via increased genipin crosslinking). All constructs were implanted interpositionally into the abdominal aorta of 21 Sprague Dawley rats (n=7, males=11, females=10) for 28 days, imaged in-vivo using ultrasound, explanted, and assessed for remodeling using immunofluorescence and two photon excitation fluorescence imaging. Compliance matched grafts remained compliance-matched in-vivo compared to the hypocompliant grafts through 4 weeks (p<0.05). Construct degradation and cellular infiltration was increased in the CMgel and HYPOgen TEVGs. Contractile smooth muscle cell markers in the proximal anastomosis of the graft were increased in the CMgel group compared to the HYPOpcl (p=0.007) and HYPOgen grafts (p=0.04). Both hypocompliant grafts also had an increased pro-inflammatory response (increased ratio of CD163 to CD86 in the mid-axial location) compared to the CMgel group. Our results suggest that compliance matching using a computational optimization approach leads to the improved acute (28 day) remodeling of TEVGs. To the authors' knowledge, this is the first in-vivo rat study investigating TEVGs that have been computationally optimized for target vessel compliance.

Establishment of Integrated Biobank for Precision Medicine and Personalized Healthcare: The Tohoku Medical Megabank Project.

The Tohoku Medical Megabank (TMM) project was established to provide creative reconstruction of the Tohoku area that suffered from a huge earthquake and ensuing tsunami (the Great East Japan Earthquake, GEJE). TMM aims to establish two large-scale genome cohorts and an integrated biobank managing biospecimen and related information. It supports community medicine by establishing next-generation medical systems through a combination of the prospective genome cohort studies with a total of 150,000 participants and genomic medicine. The strategies for genome analyses in TMM are to develop an elaborate genome reference panel by means of high-fidelity Japanese whole-genome sequence, to design custom single nucleotide polymorphism (SNP) arrays based on the reference panel, and to obtain genotype data for all the TMM cohort participants subsequently. Disease-associated genomic information and omics data, including metabolomics and microbiome analysis, provide an essential platform for precision medicine and personalized healthcare (PHC). Ethical, legal, and social issues (ELSI) and education are important for implementing genomic medicine. The major considerations of ELSI regarding each participant of the cohort studies are the respect for the autonomy and the protection of privacies. Moreover, developing and provide human resources not only for the TMM project but also for the social implementation of precision medicine and PHC is required. We started a pilot study of the return of genomic results for familial hypercholesterolemia (FH) as a target disease. TMM aims to establish solid platforms that support precision medicine and PHC based on the genomic and omics information and environmental and lifestyle factors of the individuals, which is one of the most advanced medical care beyond the evidenced-based medicine in the near future.