Delivery of topical gentamicin cream via platform wound device to reduce wound infection-A prospective, controlled, randomised, clinical study.

The platform wound device (PWD) is a wound coverage system that is designed to decrease wound infection rates by allowing for direct delivery of topical antibiotics and antimicrobials while creating a sealed, protective barrier around the area of injury. This study evaluated the safety and efficacy of the PWD as a protective dressing and a delivery system for topical antibiotics compared to the current standard of care (SoC). This was a multi-center, prospective, randomised, controlled clinical trial. The wounds were treated with the PWD with gentamicin cream or SoC dressings. The wounds were evaluated before the start of treatment and after 48-96 hours via clinical assessment, photographs, and qualitative bacterial swabs for bacterial analysis. The delivery of gentamicin via the PWD was safe and did not cause any adverse effects. The treatment decreased both inflammation and bacterial growth during the study period. No significant differences in the SoC were observed. The PWD is a transparent and impermeable polyurethane chamber that encloses and protects the injured area. The delivery of topical gentamicin via the PWD was safe and effective. Clinical assessment for infection found the PWD to be non-inferior to the current SoC treatment options.

Wound care research sponsored by the Department of Defense.

Due to the need for more information about Department of Defense sponsored wound healing research, the Wound Healing Foundation initiated the writing of this article. It briefly describes the Vision, Mission and Goals of the Department of Defense Strategic Medical Research Plan. It also describes the current objectives of Department of Defense research funding and where to access this information in detail. The grant cycle, the timing of request for proposals and some of the specifics of their requirements are also mentioned. A brief discussion of budgeting and overhead is also included.

Chronic wounds: Treatment consensus.

The Wound Healing Foundation (WHF) recognised a need for an unbiased consensus on the best treatment of chronic wounds. A panel of 13 experts were invited to a virtual meeting which took place on 27 March 2021. The proceedings were organised in the sub-sections diagnosis, debridement, infection control, dressings, grafting, pain management, oxygen treatment, outcomes and future needs. Eighty percent or better concurrence among the panellists was considered a consensus. A large number of critical questions were discussed and agreed upon. Important takeaways included that wound care needs to be simplified to a point that it can be delivered by the patient or the patient's family. Another one was that telemonitoring, which has proved very useful during the COVID-19 pandemic, can help reduce the frequency of interventions by a visiting nurse or a wound care center. Defining patient expectations is critical to designing a successful treatment. Patient outcomes might include wound specific outcomes such as time to heal, wound size reduction, as well as improvement in quality of life. For those patients with expectations of healing, an aggressive approach to achieve that goal is recommended. When healing is not an expectation, such as in patients receiving palliative wound care, outcomes might include pain reduction, exudate management, odour management and/or other quality of life benefits to wound care.

Human platelet lysate delivered via an ocular wound chamber for the treatment of corneal epithelial injuries.

Current strategies to address corneal surface defects are insufficient to successfully resolve damage caused by injury and/or disease. To address this issue, we have developed an ocular wound chamber (OWC) that creates a fluid-filled environment by encompassing damaged ocular and periocular tissues allowing for the continuous delivery of therapeutics. This study tested human platelet lysate (hPL) as a treatment for corneal epithelial defects when used with the OWC. Corneal epithelial injuries were created in anesthetized guinea pigs by debridement of the central cornea. An OWC was placed over the injured eye and animals randomly grouped followed by injection of either 20% hPL, 100% hPL, or vehicle (balanced salt solution, BSS) into the chamber. Eyes were assessed at 0, 24, 48, and 72 h using intraocular pressure (IOP), optical coherence tomography (OCT), and fluorescein imaging. Whole globes were histologically processed, and hematoxylin and eosin (H&E) stained. No differences in IOP were recorded as a result of corneal wounding, chamber placement, and/or therapeutic application. OCT images demonstrated increased corneal swelling at 48 h and 72 h in the vehicle group compared to 20% hPL. Fluorescein staining showed increased corneal re-epithelialization in the 20% and 100% hPL groups at 48 h compared to vehicle only. H&E staining revealed increased stromal cellular infiltrate in the BSS group. This study demonstrates the delivery of hPL via the OWC improves corneal re-epithelialization and supports the expanded usage of the chamber in combination with hPL to manage a variety of corneal surface injuries, diseases and/or periocular conditions.

Novel negative pressure wound therapy device without foam or gauze is effective at -50 mmHg.

Negative pressure wound therapy (NPWT) promotes healing in acute or chronic wounds. Conventional NPWT devices consist of a filler (such as foam or gauze) that covers the wound and of a permeable membrane and tubing that connects the space under the membrane to a suction pump. The permeable membrane increases airflow and thus increases the required pump capacity that can cause patient discomfort or even ischemia in wounds with compromised vascularity. In addition, foam or gauze may fragment and become colonized with bacteria over time. To mitigate these, negative aspects, we have developed a new impermeable single layer component membrane dressing to deliver NPWT that does not need a foam or gauze to function. Therefore, the purpose of this study was to introduce this novel NPWT system (platform wound device, PWD) and evaluate its usability and effectiveness in the treatment of porcine full-thickness burns. A total of 48 burn wounds were created across four Yorkshire pigs on the dorsum. Wounds were created on day 0 and continuous NPWT with -50 mmHg and - 80 mmHg was initiated immediately. Subsequently, the burns were debrided on day 3 and animals were euthanized on day 7. The efficacy of the PWD on wound healing and reduction of bacterial burden was measured and compared to wounds that did not receive NPWT. The results showed that PWD promoted wound healing by outperforming the wounds that did not receive NPWT and that PWD was efficient at reducing bacteria from the burn eschar and from the wound bed. In conclusion, this study demonstrated that PWD promoted wound healing with a negative pressure as low as -50 mmHg, which likely benefits healing and avoids potential safety issues.

Evaluation of the efficacy of cell and micrograft transplantation for full-thickness wound healing.

BACKGROUND: Skin grafting is the current standard of care in the treatment of full-thickness burns and other wounds. It is sometimes associated with substantial problems, such as poor quality of the healed skin, scarring, and lack of donor-site skin in large burns. To overcome these problems, alternative techniques that could provide larger expansion of a skin graft have been introduced over the years. Particularly, different cell therapies and methods to further expand skin grafts to minimize the need for donor skin have been attempted. The purpose of this study was to objectively evaluate the efficacy of cell and micrograft transplantation in the healing of full-thickness wounds. MATERIALS AND METHODS: Allogeneic cultured keratinocytes and fibroblasts, separately and together, as well as autologous and allogeneic skin micrografts were transplanted to full-thickness rat wounds, and healing was studied over time. In addition, wound fluid was collected, and the level of various cytokines and growth factors in the wound after transplantation was measured. RESULTS: Our results showed that both autologous and allogeneic micrografts were efficient treatment modalities for full-thickness wound healing. Allogeneic skin cell transplantation did not result in wound closure, and no viable cells were found in the wound 10 d after transplantation. CONCLUSIONS: Our study demonstrated that allogeneic micrografting is a possible treatment modality for full-thickness wound healing. The allografts stayed viable in the wound and contributed to both re-epithelialization and formation of dermis, whereas allogeneic skin cell transplantation did not result in wound closure.

Use of an ocular wound chamber for the prevention of exposure keratopathy in a guinea pig model.

Current therapies available to treat and heal ocular surface injuries and periocular burns are frequently inadequate, costly, and labor intensive. To address these limitations, we have employed a flexible, semitransparent ocular wound chamber (OWC) to provide protection as well as a watertight seal to allow for the constant delivery of therapeutics to the ocular surface and surrounding periocular tissue. This study demonstrates the safety and utilization of the OWC on uninjured eyes and in our exposure keratopathy model. For initial safety studies (N = 3 per group), the eyelids remained intact and the eye uninjured. A blepharotomy (N = 6 per group) was performed to remove the upper and lower eyelids surrounding the left (OS) eye to create our exposure keratopathy model. Right (OD) eyes served as uninjured controls in all studies. Following OWC placement, 0.5 mL HPMC gel or balanced saline solution (BSS) was injected into the chamber. Animals were monitored daily and fully assessed via white light, fluorescein, and OCT imaging at least through 72 hours post OWC placement. In studies that included a blepharotomy, skin samples were analyzed by multiplex cytokine analysis. Results of safety experiments revealed no significant differences between treatment groups in corneal thickness, fluorescein staining, OCT imaging, or histological eye or skin sections when compared to control eyes. In our exposure keratopathy model, OWC treated eyes showed significantly less fluorescein uptake and also were found to have significantly lower levels of cytokines IL-13 and IL-5 in skin samples. These results demonstrate for the first time that treatment using the OWC device is not only safe, but significantly protects against blepharotomy-induced exposure keratopathy. As a whole, this study advances our overall efforts to develop a feasible solution to treat ocular surface injuries, infections, and periocular burns.

The effect of pH on cell viability, cell migration, cell proliferation, wound closure, and wound reepithelialization: In vitro and in vivo study.

Wound microenvironment plays a major role in the process of wound healing. It contains various external and internal factors that participate in wound pathophysiology. The pH is an important factor that influences wound healing by changing throughout the healing process. Several previous studies have investigated the role of pH in relation to pathogens but studies concentrating on the effects of pH on wound healing itself are inconclusive. The purpose of this study was to comprehensively and in a controlled fashion investigate the effect of pH on wound healing by studying its effect on human primary keratinocyte and fibroblast function in vitro and on wound healing in vivo. In vitro, primary human keratinocytes and fibroblasts were cultured in different levels of pH (5.5-12.5) and the effect on cell viability, proliferation, and migration was studied. A rat full-thickness wound model was used to investigate the effect of pH (5.5-9.5) on wound healing in vivo. The effect of pH on inflammation was monitored by measuring IL-1 α concentrations from wounds and cell cultures exposed to different pH environments. Our results showed that both skin cell types tolerated wide range of pH very well. They further demonstrated that both acidic and alkaline environments decelerated cell migration in comparison to neutral environments and interestingly alkaline conditions significantly enhanced cell proliferation. Results from the in vivo experiments indicated that a prolonged, strongly acidic wound environment prevents both wound closure and reepithelialization while a prolonged alkaline environment did not have any negative impact on wound closure or reepithelialization. Separately, both in vitro and in vivo studies showed that prolonged acidic conditions significantly increased the expression of IL-1 α in fibroblast cultures and in wound fluid, whereas prolonged alkaline conditions did not result in elevated amounts of IL-1 α.

Transforming growth factor ß1 regulates the expression of CCN2 in human keratinocytes via Smad-ERK signalling.

Connective tissue growth factor (CCN2/CTGF) and transforming growth factor ß1 (TGF-ß1) are important regulators of skin wound healing, but controversy remains regarding their expression in epithelial cell lineages. Here, we investigate the expression of CCN2 in keratinocytes during reepithelialisation and its regulation by TGF-ß1. CCN2 was detected in the epidermis of healing full-thickness porcine wounds. Human keratinocytes were incubated with or without 10 ng/ml TGF-ß1, and signalling pathways were blocked with 10-µM SIS3 or 20-µM PD98059. Semi-quantitative real-time PCR was used to study CCN2 mRNA expression, and western blot was used to measure CCN2, phosphorylated-ERK1/2, ERK1/2, phosphorylated-Smad3 and Smad2/3 proteins. CCN2 was transiently expressed in neoepidermis at the leading edge of the wound in vivo. In vitro, CCN2 expression was induced by TGF-ß1 at 2 hours (7·5 ± 1·9-fold mRNA increase and 3·0 ± 0·6-fold protein increase) and 12 hours (5·4 ± 1·9-fold mRNA increase and 3·3 ± 0·6-fold protein increase). Compared with inhibiting the SMAD pathway, inhibiting the mitogen-activated protein kinase (MAPK) pathway was more effective in reducing TGF-ß1-induced CCN2 mRNA and protein expression. Inhibition of the MAPK pathway had minimal impact on the activity of the SMAD pathway. CCN2 is expressed in keratinocytes in response to tissue injury or TGF-ß1. In addition, TGF-ß1 induces CCN2 expression in keratinocytes through the ras/MEK/ERK pathway. A complete understanding of CCN2 expression in keratinocytes is critical to developing novel therapies for wound healing and cutaneous malignancy.

The effect of local hyperglycemia on skin cells in vitro and on wound healing in euglycemic rats.

BACKGROUND: Multiple previous studies have established that high systemic blood glucose concentration impairs skin wound healing. However, the effects of local hyperglycemia on wound healing are not well defined. Comprehensive animal studies and in vitro studies using both fibroblasts and keratinocytes are lacking. MATERIALS AND METHODS: Primary keratinocytes and fibroblasts were isolated from discarded human tissue, cultured under different concentrations of glucose, and the effect on cell function was examined. In addition, a rat full-thickness wound model was used to topically treat the wounds with different glucose concentrations and the effect on wound closure and re-epithelialization was investigated over time. RESULTS: The cell viability experiments indicated that both keratinocytes and fibroblasts endure high glucose well and concentrations under 26 mM did not have a remarkable effect on their viability over time. Moderate addition of glucose (10 mM) boosted fibroblast proliferation (6-fold) but did not have an effect on keratinocyte proliferation. In both keratinocytes and fibroblasts, glucose inhibited their migration and already the addition of 5.6-mM glucose had an inhibitory effect. In vivo experiments showed that full-thickness wounds treated with topical glucose had impaired wound closure and lower re-epithelialization rate in comparison to nontreated control wounds. The results also showed that higher glucose concentrations inhibited wound healing more efficiently. CONCLUSIONS: In conclusion, our study indicates that high glucose inhibits both keratinocyte and fibroblast migration as well as wound healing in vivo in a concentration dependent manner.

Endotoxin-induced inflammation in a rodent model up-regulates IL-1a expression and CD45+ leukocyte recruitment and increases the rate of reepithelialization and wound closure.

Wound healing is traditionally divided into inflammation, proliferation, and remodeling phases. Several inflammatory mediators and cells regulate the inflammation phase. The specific roles for different mediators have not been clearly defined. The effects of inflammation phase modulation on wound healing were evaluated in this study. Rat full-thickness wounds were divided into different experimental groups: (1) sterile hyper-inflammatory wounds/endotoxin (topical endotoxin), (2) sterile hypo-inflammatory/inhibitor group (cocktail of topical COX-1 plus COX-2 plus lipoxygenase inhibitors), and (3) control groups: topical saline or DMSO. After full-thickness wound creation, custom-made titanium chambers enclosed the wound, creating an isolated well-controlled environment. Wound healing was followed over time; tissue biopsies and wound fluid samples were collected on days 1, 4, and 8 postoperatively. The validity of the inflammation model was confirmed by increased IL-1a expression, increased CD45+ leukocytes recruitment in the hyper-inflamed group as compared to the inhibitor and control groups. The reepithelialization percentage was significantly increased in the endotoxin group as compared to the inhibitor group on day 4 (60.75 vs. 22.05, p-value <0.05) and both the inhibitor and the control group on day 8 (control group: 63.2%, inhibitor group: 28.9%, endotoxin group: 84.2%, p-value <0.05). Also, the macroscopic wound closure was increased in the endotoxin group as compared to the inhibitor group and control group both on day 4 (control group: 69.9%, inhibitor group: 62.9%, endotoxin group: 81.9%, p-value <0.05) and on day 8 (control group: 68.5%, inhibitor group: 69.1%, endotoxin group: 83.7%, p-value <0.05). Endotoxin-induced sterile inflammation up-regulates IL-1a expression and CD45+ leukocyte recruitment and results in faster rate of wound reepithelialization and wound closure in full-thickness rodent wounds. Conversely, the wound reepithelialization and wound closure can be significantly delayed on treatment with a combination of cyclooxygenase and lipoxygenase inhibitors.

Titanium wound chambers for wound healing research.

Standardized and reproducible animal models are crucial in medical research. Rodents are commonly used in wound healing studies since, they are easily available, affordable and simple to handle and house. However, the most significant limitation of rodent models is that the wounds heal by contraction while in humans the primary mechanisms of healing are reepithelialization and granulation tissue formation. The robust contraction results in faster wound closure that complicates the reproducibility of rodent studies in clinical trials. We have developed a titanium wound chamber for rodent wound healing research. The chamber is engineered from two pieces of titanium and is placed transcutaneously on the dorsum of a rodent. The chamber inhibits wound contraction and provides a means for controlled monitoring and sampling of the wound environment in vivo with minimal foreign body reaction. This technical report introduces two modalities utilizing the titanium chambers in rats: (1) Wound in a skin island model and, (2) Wound without skin model. Here, we demonstrate in rats how the "wound in a skin island model" slows down wound contraction and how the "wound without skin" model completely prevents the closure. The titanium wound chamber provides a reproducible standardized models for wound healing research in rodents.

Full-thickness porcine burns infected with Staphylococcus aureus or Pseudomonas aeruginosa can be effectively treated with topical antibiotics.

Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wound healing, delay in treatment, disability, or death. Traditional approach centers on early debridement, fluid resuscitation, and adjunct intravenous antibiotics. These modalities often prove inadequate in burns, where compromised local vasculature limits the tissue penetration of systemic antibiotics. Here, we demonstrate the treatment of infected burns with topical delivery of ultrahigh concentrations of antibiotics. Standardized burns were inoculated with Staphylococcus aureus or Pseudomonas aeruginosa. After debridement, burns were treated with either gentamicin (2 mg/mL) or minocycline (1 mg/mL) at concentrations greater than 1,000 times the minimum inhibitory concentration. Amount of bacteria was quantified in tissue biopsies and wound fluid following treatment. After six days of gentamicin or minocycline treatment, S. aureus counts decreased from 4.2 to 0.31 and 0.72 log CFU/g in tissue, respectively. Similarly, P. aeruginosa counts decreased from 2.5 to 0.0 and 1.5 log CFU/g in tissue, respectively. Counts of both S. aureus and P. aeruginosa remained at a baseline of 0.0 log CFU/mL in wound fluid for both treatment groups. The findings here demonstrate that super-therapeutic concentrations of antibiotics delivered topically can rapidly reduce bacterial counts in infected full-thickness porcine burns. This treatment approach may aid wound bed preparation and accelerate time to grafting.

A Time Study of Plastic Surgery Residents.

BACKGROUND: Resident work hours are under scrutiny and have been subject to multiple restrictions. The studies supporting these changes have not included data on surgical residents. We studied the workday of a team of plastic surgery residents to establish prospective time-study data of plastic surgery (PRS) residents at a single tertiary-care academic medical center. METHODS: Five trained research assistants observed all residents (n = 8) on a PRS service for 10 weeks and produced minute-by-minute activity logs. Data collection began when the team first met in the morning and continued until the resident being followed completed all non-call activities. We analyzed our data from 3 perspectives: 1) time spent in direct patient care (DPC), indirect patient care, and didactic activities; 2) time spent in high education-value activities (HEAs) versus low education-value activities; and 3) resident efficiency. We defined HEAs as activities that surgeons must master; other activities were LEAs. We quantified resident efficiency in terms of time fragmentation and time spent waiting. RESULTS: A total of 642.4 hours of data across 50 workdays were collected. Excluding call, residents worked an average of 64.2 hours per week. Approximately 50.7% of surgical resident time was allotted to DPC, with surgery accounting for the largest segment of this time (34.8%). Time spent on HEAs demonstrated trended upward with higher resident level (P = 0.086). Time in spent in surgery was significantly associated with higher resident levels (P < 0.0001); 57.7% of activities require 4 minutes or less, suggesting that resident work was highly fragmented. Residents spent 10.7% of their workdays waiting for other services. CONCLUSIONS: In this first-time study of PRS residents, we found that compared with medicine trainees, surgical residents spent 3.23 times more time on DPC. High education-value activities comprised most of our residents' workdays. Surgery was the leading component of both DPC and HEAs. Our residents were highly efficient and fragmented, with the majority of all activities requiring 4 minutes or less. Residents spent a large portion of their time waiting for other services. In light of these data, we suggest that future changes to residency programs be pilot tested, with preimplantation and postimplementation time studies performed to quantify the changes' impact.

Cdc42 and p190RhoGAP activation by CCN2 regulates cell spreading and polarity and induces actin disassembly in migrating keratinocytes.

Cell migration requires spatiotemporal integration of signals that regulate cytoskeletal dynamics. In response to a migration-promoting agent, cells begin to polarise and extend protrusions in the direction of migration. These cytoskeletal rearrangements are orchestrated by a variety of proteins, including focal adhesion kinase (FAK) and the Rho family of GTPases. CCN2, also known as connective tissue growth factor, has emerged as a regulator of cell migration but the mechanism by which CCN2 regulates keratinocyte function is not well understood. In this article, we sought to elucidate the basic mechanism of CCN2-induced cell migration in human keratinocytes. Immunohistochemical staining was used to demonstrate that treatment with CCN2 induces a migratory phenotype through actin disassembly, spreading of lamellipodia and re-orientation of the Golgi. In vitro assays were used to show that CCN2-induced cell migration is dependent on FAK, RhoA and Cdc42, but independent of Rac1. CCN2-treated keratinocytes displayed increased Cdc42 activity and decreased RhoA activity up to 12 hours post-treatment, with upregulation of p190RhoGAP. An improved understanding of how CCN2 regulates cell migration may establish the foundation for future therapeutics in fibrotic and neoplastic diseases.

Three patients with full facial transplantation.

Unlike conventional reconstruction, facial transplantation seeks to correct severe deformities in a single operation. We report on three patients who received full-face transplants at our institution in 2011 in operations that aimed for functional restoration by coaptation of all main available motor and sensory nerves. We enumerate the technical challenges and postoperative complications and their management, including single episodes of acute rejection in two patients. At 6 months of follow-up, all facial allografts were surviving, facial appearance and function were improved, and glucocorticoids were successfully withdrawn in all patients.

The external microenvironment of healing skin wounds.

The skin wound microenvironment can be divided into two main components that influence healing: the external wound microenvironment, which is outside the wound surface; and the internal wound microenvironment, underneath the surface, to which the cells within the wound are exposed. Treatment methods that directly alter the features of the external wound microenvironment indirectly affect the internal wound microenvironment due to the exchange between the two compartments. In this review, we focus on the effects of temperature, pressure (positive and negative), hydration, gases (oxygen and carbon dioxide), pH, and anti-microbial treatment on the wound. These factors are well described in the literature and can be modified with treatment methods available in the clinic. Understanding the roles of these factors in wound pathophysiology is of central importance in wound treatment.

Deep Temporal Fascia Coverage of the Loading Weight in Paralytic Lagopthalmos Patients.

INTRODUCTION: Use of a weight for lagopthalmos secondary to facial nerve paralysis is the standard technique for achieving effective eyelid closure. However, because of thin and mobile skin of the eyelid and closely opposed implant, there is increased risk of complications such as implant visibility, contour deformity, and implant extrusion. SURGICAL TECHNIQUE: The authors describe a surgical technique involving coverage of the implanted weight with contralateral deep temporal fascia. The deep temporal fascia serves as a hammock to give an interventional barrier to prevent dehiscence of the pocket and extrusion of the ocular implant. It also provides camouflage to the irregular borders of the gold weight. RESULTS AND CONCLUSIONS: Autologous coverage of gold weight with deep temporal fascia provides an effective solution to commonly associated complications with the gold weights. The use of contralateral temporal fascia preserves the ipsilateral temporalis muscle for future facial nerve reconstruction.

Assessing quality of healing in skin: review of available methods and devices.

The process of wound healing is dynamic and takes place over months to years, during which there is a resolution of angiogenesis, continued wound contraction, and connective tissue remodeling. The outcome of this process is most commonly the formation of a scar, defined as a fibrous tissue replacing normal tissues destroyed by injury or disease. Scars often have a lowered or total loss of vital skin functions and imbue a large burden on both the patient and the health care system as a whole. Scar treatments are plentiful but are often unsatisfactory or inconsistent. No single treatment method has been universally adopted. To evaluate the clinical treatment as well as research focused on developing novel methods for scar management, objective studies of the progression of scar formation and the properties of mature scars are needed. Several parameters, including barrier function as well as mechanical and physiological properties, need to be taken into account when both categorizing and treating healing wounds and scars. To date, there is no available methodology that provides a comprehensive evaluation of a scar's properties. This review aims at presenting an overview of available scar assessment methods and devices, ranging from analysis of collagen properties in tissue biopsies to noninvasive methods for studies of mechanical parameters such as breaking strength and skin elasticity. In the cases where conclusive studies have been performed, the differences between normal skin and scar with respect to the above parameters are presented. Furthermore, this review highlights areas where the development of additional modalities are needed.

CCN2 promotes keratinocyte adhesion and migration via integrin α5ß1.

BACKGROUND: CCN2, (a.k.a. connective tissue growth factor and CTGF) has emerged as a regulator of cell migration. While the importance of CCN2 for the fibrotic process in wound healing has been well studied, the effect of CCN2 on keratinocyte function is not well understood. In this study, we investigated the mechanism behind CCN2-driven keratinocyte adhesion and migration. MATERIALS AND METHODS: Adhesion assays were performed by coating wells with 10 µg/ml fibronectin (FN) or phosphate-buffered saline (PBS). Keratinocytes were seeded in the presence or absence of 200 ng/ml CCN2, 5 mmol/l ethylenediaminetetraacetic acid, 10 mmol/l cations, 500 µl arginine-glycine-aspartic acid (RGD), 500 µM arginine-glycine-glutamate-serine (RGES), and 10 µg/ml anti-integrin blocking antibodies. Migration studies were performed using a modified Boyden chamber assay. Quantitative PCR was used to study the effect of CCN2 on integrin subunit mRNA expression. To block intracellular pathways, keratinocytes were pretreated with 20 µM PD98059 (MEK-1 inhibitor) or 20 µM PF573228 (FAK inhibitor) for 60 min prior the addition of CCN2. Western blot was used to measure CCN2, p-ERK1/2, and ERK1/2. RESULTS: CCN2 enhanced keratinocyte adhesion to fibronectin via integrin α5ß1. The addition of anti-integrin α5ß1 antibodies reduced CCN2-mediated keratinocyte migration. In addition, CCN2 regulated mRNA and protein expression of integrin subunits α5 and ß1. CCN2 activated the FAK-MAPK signaling pathway, and pretreatment with MEK1-specific inhibitor PD98059 markedly reduced CCN2-induced keratinocyte migration. CONCLUSIONS: Our results demonstrate that CCN2 enhances keratinocyte adhesion and migration through integrin α5ß1 and activation of the FAK-MAPK signaling cascade.