Autologous Cultured Bone Marrow-Derived Mesenchymal Stem Cells in a Fibrin Spray to Treat Venous Ulcers: A Randomized Controlled Double-Blind Pilot Study.

We treated a small cohort of venous ulcers that were very unresponsive to standard and advanced therapies with autologous cultured bone marrow-derived mesenchymal stem cells (MSCs). This pilot clinical trial was randomized, controlled, and double-blinded. Subjects were treated with either normal saline (Group A), fibrin spray alone (Group B), or MSCs in fibrin (1 million cells/cm2 of wound bed surface) (Group C).

An in vitro priming step increases the expression of numerous epidermal growth and migration mediators in a tissue-engineering construct.

An FDA-approved, prototypic, living, bilayered skin construct (BSC) has been used for non-healing wounds. Using this particular construct as proof of principle, we hypothesized that an in vitro 'priming' step may enhance its repertoire of expression of key mediators and genes. The priming step used here was incubation in Dulbecco's modified Eagle's medium (DMEM) for 24 h at 37°C and 5% CO , with or without construct meshing.

Bone marrow cell mobilization by the systemic use of granulocyte colony-stimulating factor (GCSF) improves wound bed preparation.

Innovative approaches are needed to accelerate the healing of human chronic wounds not responding to conventional therapies. An evolving and promising treatment is the use of stem cells. Our group has previously described the use of expanded (in vitro) autologous stem cells aspirated from human bone marrow and applied topically in a fibrin spray to human acute and chronic wounds.

Topical delivery of cultured stem cells to human non-healing wounds: GMP facility development in an academic setting and FDA requirements for an IND and human testing.

With increasing emphasis on translational research, the need for appropriate regulatory oversight and approval has become essential. The requirements of the Food and Drug Administration (FDA) for Investigational New Drug (IND) exemption in studies that are investigator-initiated have become increasingly stringent. Moreover, academic institutions have not had substantial experience in establishing Good Manufacturing Practice (GMP) facilities required for manipulating human cells in vitro and for chemical or biochemical manufacturing.

Differential keratin expression during epiboly in a wound model of bioengineered skin and in human chronic wounds.

Epiboly represents the process by which keratinocytes migrate to envelop a surface. The authors have been investigating a living bilayered skin construct (BSC) that is used in the treatment of lower extremity wounds due to venous insufficiency and diabetes. The construct demonstrates epiboly after injury and incubation in vitro, and this model may be useful for studying epidermal migration and the process of skin maturation.

Fibroblasts from non-healing human chronic wounds show decreased expression of beta ig-h3, a TGF-beta inducible protein.

Background: Increasing evidence shows persistent phenotypic alterations in fibroblasts from non-healing human chronic wounds, which may result in faulty extracellular matrix deposition and keratinocyte migration. We have previously shown that these cells are characterized by morphological changes, low proliferative potential and unresponsiveness to TGF-beta1, and down regulated phosphorylation of Smad 2/3 and p42/44 MAPK from decreased expression of the TGF-beta type II receptor.

Objective: To identify genes and proteins that may be differentially expressed in chronic wounds and their cultured fibroblasts.

Autologous bone marrow-derived cultured mesenchymal stem cells delivered in a fibrin spray accelerate healing in murine and human cutaneous wounds.

The nonhematopoietic component of bone marrow includes multipotent mesenchymal stem cells (MSC) capable of differentiating into fat, bone, muscle, cartilage, and endothelium. In this report, we describe the cell culture and characterization, delivery system, and successful use of topically applied autologous MSC to accelerate the healing of human and experimental murine wounds. A single bone marrow aspirate of 35-50 mL was obtained from patients with acute wounds (n = 5) from skin cancer surgery and from patients with chronic, long-standing, nonhealing lower extremity wounds (n = 8).

Migration of the epidermal over the dermal component (epiboly) in a bilayered bioengineered skin construct.

A bilayered bioengineered living skin construct (LSC) consisting of viable human neonatal keratinocytes over a collagenous dermis seeded with dermal fibroblasts has been used extensively in difficult-to heal human wounds. Its biological properties include production of several mediators, cytokines, and growth factors and the ability to heal itself upon injury. In this study, we investigated the process of keratinocyte migration in LSC.

Human beta-defensin-2 expression is increased in chronic wounds.

First identified in psoriatic epidermis and subsequently in other inflammatory cutaneous lesions, human beta-defensin-2 (hbetaD-2) is one of two endogenous antimicrobial peptides related to defensins in plants and animals. Our objective was to determine the expression of hbetaD-2 after injury and in chronic wounds. Biopsies of normal ipsilateral thigh skin and wound edges were taken from nine consecutive patients with venous leg ulcers (day 1) and from the same biopsy sites 2 days later (day 3).

Fibroblasts from chronic wounds show altered TGF-beta-signaling and decreased TGF-beta Type II receptor expression.

Chronic wounds are characterized by failure to heal in a defined time frame. However, the pathogenic steps leading from the etiological factors to failure to heal are unknown. Recently, increasing evidence suggests that resident cells in chronic wounds display a number of critical abnormalities, including senescence and unresponsiveness to the stimulatory action of transforming growth factor-beta1 (TGF-beta1).

Transcriptional activation of alpha 1(III) procollagen gene in Tsk2/+ dermal fibroblasts.

Transient transfection experiments into Tsk2/+ and normal dermal fibroblasts were performed using four successively shorter Col3a1 promoter deletion constructs: #103, #110, #114, and #120 fused to the chloramphenicol-acetyl-transferase (CAT) reporter gene. The transcriptional activity in Tsk2/+ and normal dermal fibroblasts driven by the three longer constructs was equal. With the shortest construct, #120 (-96 to +16bp) the transcriptional activity in Tsk2/+ fibroblasts was 25 times higher than in normal fibroblasts.

Low oxygen tension stimulates collagen synthesis and COL1A1 transcription through the action of TGF-beta1.

Recent findings point to low oxygen tension (hypoxia) as an important mechanism for the expression of several eukaryotic genes. We have previously shown that hypoxia (2% O2), when compared to standard oxygen tension (20% O2), upregulates the mRNA levels of the human alpha1(I) (COL1A1) procollagen gene and transforming growth factor-beta1 (TGF-beta1) in human dermal fibroblasts. In this report, we determined the effect of hypoxia on collagen synthesis and transcription.