Decellularized Placental Sponge Seeded with Human Mesenchymal Stem Cells Improves Deep Skin Wound Healing in the Animal Model.

Skin injuries lead to a large burden of morbidity. Although numerous clinical and scientific strategies have been investigated to repair injured skin, optimal regeneration therapy still poses a considerable obstacle. To address this challenge, decellularized extracellular matrix-based scaffolds recellularized with stem cells offer significant advancements in skin regeneration and wound healing. Herein, a decellularized human placental sponge (DPS) was fabricated using the decellularization and freeze-drying technique and then recellularized with human adipose-derived mesenchymal cells (MSCs). The biological and biomechanical properties and skin full-thickness wound healing capacity of the stem cells-DPS constructs were investigated in vitro and in vivo. The DPS exhibited a uniform 3D microstructure with an interconnected pore network, 89.21% porosity, a low degradation rate, and good mechanical properties. The DPS and MSCs-DPS constructs were implanted in skin full-thickness wound models in mice. An accelerated wound healing was observed in the wounds implanted with the MSCs-DPS construct when compared to DPS and control (wounds with no treatment) during 7 and 21 days postimplantation follow-up. In the MSCs-DPS group, the wound was completely re-epithelialized, the epidermis layer was properly organized, and the dermis and epidermis' bilayer structures were restored after 7 days. Our findings suggest that DPS is an excellent carrier for MSC culture and delivery to skin wounds and now promises to proceed with clinical evaluations.

Antimicrobial peptide-loaded decellularized placental sponge as an excellent antibacterial skin substitute against XDR clinical isolates.

Post-wound infections have remained a serious threat to society and healthcare worldwide. Attempts are still being made to develop an ideal antibacterial wound dressing with high wound-healing potential and strong antibacterial activity against extensively drug-resistant bacteria (XDR). In this study, a biological-based sponge was made from decellularized human placenta (DPS) and then loaded with different concentrations (0, 16 µg/mL, 32 µg/mL, 64 µg/mL) of an antimicrobial peptide (AMP, CM11) to optimize an ideal antibacterial wound dressing. The decellularization of DPS was confirmed by histological evaluations and DNA content assay. The DPS loaded with different contents of antimicrobial peptides (AMPs) showed uniform morphology under a scanning electron microscope (SEM) and cytobiocompatibility for human adipose tissue-derived mesenchymal stem cells. Antibacterial assays indicated that the DPS/AMPs had antibacterial behavior against both standard strain and XDR Acinetobacter baumannii in a dose-dependent manner, as DPS loaded with 64 µg/mL showed the highest bacterial growth inhibition zone and elimination of bacteria under SEM than DPS alone and DPS loaded with 16 µg/mL and 32 µg/mL AMP concentrations. The subcutaneous implantation of all constructs in the animal model demonstrated no sign of acute immune system reaction and graft rejection, indicating in vivo biocompatibility of the scaffolds. Our findings suggest the DPS loaded with 64 µg/mL as an excellent antibacterial skin substitute, and now promises to proceed with pre-clinical and clinical investigations.

Epidemiological data of national Kawasaki disease registry in Iran, 2007-2019.

Introduction: Kawasaki disease(KD) is a vasculitis of childhood that tends to influence the coronary arteries. There is no national data about the prevalence of KD in Iran. This study aimed to perform a national registry in Iran for 13 years. Methods: In this retrospective study, the data for KD extracted from medical records of <19 year-old patients admitted to tertiary hospitals in Iran between 2007 and 2019 were recorded in the national KD registry system. Age, admission date, gender, location, and presence of KD criteria, laboratory and echocardiography findings, and treatment modalities were evaluated. Complete KD was considered if ≥4 clinical criteria of the KD existed and otherwise, incomplete KD was considered. Results: Data from 1,682 KD patients including 999(59.39%) boys and 683(40.61%) girls and male/female ratio of 1.46 were evaluated. The mean age was 3.08 ± 2.49 years and 1465(87%) were living in urban regions. The yearly incidence of the disease was between 2.62 to 3.03 from 2015 to 2019. The highest age-specific incidence was observed in children <1-year-old. Incomplete and resistant KD included 1,321(78.54%) and 9(0.54%) patients, respectively. Abnormal echocardiography was detected in 619(36.80%) patients. Leukocytosis, with dominancy of neutrophils, anemia, thrombocytosis and increased ESR and CRP were the most noticeable laboratory findings. No death due to KD disease was reported. Conclusion: Based on this study, most of the KD cases are presented with atypical presentation in Iran. So, increasing awareness of primary healthcare workers by educating and updating their data is very important in timely diagnosis and management of the disease.