Porcine Collagen Research Articles

Resolution of Non-Diabetic Intractable Wounds with Severe Comorbidities Using Autologous Micrografts

The wound healing process is a complex mechanism related to many factors, such as the patient’s comorbidity, blood flow, and nutritional status. This study aimed to retrospectively evaluate patients affected by various disease states and treated with Rigenera® technology, a standardized micrograft preparation system. A total of 8 patients were treated with a suspension of autologous micrografts obtained from mechanical disaggregation of small pieces of skin tissue. The micrografts suspension was applied alone to the wound or in combination with porcine collagen scaffolds directly onto the wound as described in the text. Across all cases, there was marked improvement in wound healing, with a mean healing time of 103 days and a reduction of the diameter of the wounds by 54%. Notably, the use of micrografts resulted in an overall higher quality of life for the patients. This simple and low-cost micrografting procedure that can promote wound healing of different kinds of chronic non-healing wounds and does not require postoperative rest.

Combined Oxygen–Ozone and Porcine Injectable Collagen Therapies Boosting Efficacy in Low Back Pain and Disability

Background/Objectives: Intervertebral disc degeneration is the most common cause of low back pain (LBP), and lumbosciatica is a major challenge to healthcare systems worldwide. For years, ozone therapy has been used with excellent results in intervertebral disc disease and in patients with LBP. In vitro studies have demonstrated the positive action of porcine collagen in extracellular matrix remodeling and homeostasis. These tissue changes, associated with LBP, may suggest an indication for combined ozone/collagen treatment in patients with LBP. However, no studies have been reported regarding this combination of treatments. Methods: The present work compared retrospective data of two treatment groups (each of 10 LBP patients): (A) oxygen–ozone therapy (OOT) vs. (B) OOT plus porcine collagen type 1 injections (COL I). Pain intensity and physiological function were assessed by the numerical rating scale (NSR) method. The Roland–Morris questionnaire was used to assess disability. Patient data were acquired before, during, and at the six-month follow-up. Significant differences were assessed by ANOVA and Student’s t-test. Results: The analyses revealed significant statistical differences comparing the two arms, where the (OOT+COL I) treatment demonstrated a booster efficacy in pain (a reduction of 62% vs. 35%), while the questionnaire revealed a reduction in disability (70% vs. 31%). Conclusions: Therefore, this combination therapy (oxygen–ozone plus porcine injectable collagen) might be a promising approach for the management of patients with LBP.

Collagen Paste Injection in Crohn's Disease Perianal Fistula: Long-term Outcomes of a Pilot, Prospective Cohort Study.

Crohn's perianal fistula represents a challenging condition to treat. Sphincters-preserving surgical techniques are increasingly being adopted as repeated surgical procedures may lead to various degrees of incontinence. This prospective study aims to assess the long-term efficacy of collagen paste application in patients with simple and complex Crohn's perianal fistulas. Patients with Crohn's perianal fistula (simple or complex) and inactive luminal disease were enrolled. The fistula tract was treated by curettage and injection of acellular, porcine dermal collagen paste between 2019 and 2021. The primary endpoint was the clinical healing of the fistula at 12 and 24 months, defined as the absence of suppuration on clinical examination. The trial was preregistered on a public repository (ClinicalTrials.gov; NCT03776825). Fourteen patients were included in the study, ten patients (71%) had complex perianal fistula. All patients underwent previous fistula operations. Nine patients (64%) reached complete clinical remission at 12 months, two patients (14%) had a clinical recurrence six months after surgery, and three patients (21%) at 12 months follow-up. Three relapsed patients presented postoperative abscesses. Twelve patients (86%) were followed up at 24 months, no further clinical recurrences or complications were observed and the complete healing rate was 58%. No continence disturbances were recorded after collagen paste injection. The results suggest that collagen paste injection may represent a safe and effective option for Crohn's perianal fistulas, worth further investigation in larger trials.

Quantitative Assessment of New Frontiers in Dermatochalasis and Periorbital Hyperpigmentation Treatment: The Role of Cross-Linked Porcine Collagen.

Collagen dermal fillers have shown efficacy in addressing age-related changes in facial appearance. However, their potential in rejuvenating the periorbital region remains unexplored. The aim of this study was to evaluate the effectiveness, clinical safety, and patient satisfaction associated with the utilization of collagen dermal fillers in individuals with dermatochalasis and periorbital hyperpigmentation. This study was reviewed and approved by the institutional review board of China Medical University Hospital (IRB No. CMUH107-REC2-157). Adults diagnosed with dermatochalasis or periorbital hyperpigmentation received periorbital injections of a sterile cross-linked highly-purified specific antigen free porcine dermal collagen (FACIALGAIN® Collagen Implant with Lidocaine, Sunmax Biotechnology Co. Ltd., Taipei, Taiwan) and were assessed for hydration, elasticity, pigmentation index, redness index, lightness value, and density with the DermaLab® Combo Multiparameter Skin Analysis System (Cortex Technology, Hadsund, Denmark) and Cutometer® Dual MPA 580 (Courage+Khazaka electronic GmbH, Köln, Germany). Data was collected prior to injection and at 1 week, 4 weeks, and 12 weeks after injection. Patient satisfaction on volume augmentation, decrease in hyperpigmentation, persistence, and overall satisfaction were also recorded. A total of 12 samples each were recruited for dermatochalasis and periorbital hyperpigmentation. For dermatochalasis subjects, hydration of the periorbital tissue significantly increased at week 1 and 4 (p = 0.011 and p = 0.015). Elasticity decreased by week 4 and persisted until week 12 (p = 0.001 and 0.014). For periorbital hyperpigmentation patients, lightness value increased significantly starting week 1 (p = 0.016), tapering off at week 12. Elasticity decreased by week 4 and persisted until week 12 (p = 0.002 and p = 0.002). Median overall patient satisfaction was 4 out of 5 for the dermatochalasis group and 4.5 out of 5 for the periorbital hyperpigmentation group, with a mild but insignificant decrease by week 12. DermaLab® Combo and Cutometer® Dual MPA 580 are considered effective methods for evaluating patients undergoing dermal filler injections. The utilization of cross-linked porcine collagen dermal filler injections can serve as a minimally invasive approach to enhance skin laxity in dermatochalasis and address discoloration in periorbital hyperpigmentation. However, it is important to note that regular treatments may be necessary to sustain the desired outcomes. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/0026 .

Changes in Texture and Collagen Properties of Pork Skin during Salt-Enzyme-Alkali Tenderization Treatment.

The effects of salt-enzyme-alkali progressive tenderization treatments on porcine cortical conformation and collagen properties were investigated, and their effectiveness and mechanisms were analyzed. The tenderization treatment comprised three treatment stages: CaCl2 (25 °C/0-30 min), papain (35 °C/30-78 min), and Na2CO3 (25 °C/78-120 min). The textural, microscopic, and collagenous properties (content, solubility, and structure) of pork skin were determined at the 0th, 30th, 60th, 90th, and 120th min of the treatment process. The results showed that the shear force, hardness, and chewability of the skin decreased significantly (p < 0.05), and the elasticity exhibited a gradual increase with the progression of tenderization. The content and solubility of collagen showed no significant change at the CaCl2 treatment stage. However, the soluble collagen content increased, the insoluble collagen content decreased, and the collagen solubility increased by 18.04% during the subsequent treatment with papain and Na2CO3. Meanwhile, the scanning electron microscopy results revealed that the regular, wavy structure of the pig skin collagen fibers gradually disappeared during the CaCl2 treatment stage, the overall structure revealed expansion, and the surface microscopic pores gradually increased during the papain and Na2CO3 treatment stages. The findings of the Fourier transform infrared spectroscopy analysis indicated that the hydrogen bonding interactions between the collagen molecules and the C=O, N-H and C-N bonds in the subunit structure of collagen were substantially altered during treatment and that the breakage of amino acid chains and reduction in structural ordering became more pronounced with prolonged treatment. In the tertiary structure, the maximum emission wavelength was blue-shifted and then red-shifted, and the fluorescence intensity was gradually weakened. The surface hydrophobicity was slowly increased. The salt-enzyme-alkali tenderization treatment considerably improved the physical properties and texture of edible pork skins by dissolving collagen fibers and destroying the structure of collagen and its interaction force.

Osseointegration of Anodized vs. Sandblasted Implant Surfaces in a Guided Bone Regeneration Acute Dehiscence-Type Defect: An InVivo Experimental Mandibular Minipig Model.

This controlled preclinical study analyzed the effect of implant surface characteristics on osseointegration and crestal bone formation in a grafted dehiscence defect minipig model. A standardized 3 mm × 3 mm acute-type buccal dehiscence minipig model grafted with deproteinized bovine bone mineral and covered with a porcine collagen membrane after 2 and 8 weeks of healing was utilized. Crestal bone formation was analyzed histologically and histomorphometrically to compare three implant groups: (1) a novel, commercially available, gradient anodized (NGA) implant, to two custom-made geometric replicas of implant "1," (2) a superhydrophilic micro-rough large-grit sandblasted and acid-etched surface, and (3) a relatively hydrophobic micro-rough large-grit sandblasted and acid-etched surface. At 2 and 8 weeks, there was no difference between the amount and height of newly formed bone (NBH, new bone height; BATA, bone area to total area) for any of the groups (p > 0.05). First bone-to-implant contact (fBIC) and vertical bone creep (VBC) at 2 and 8 weeks were significantly increased for Groups 2 and 3 compared to Group 1 (p < 0.05). At 8 weeks, osseointegration in the dehiscence (dehiscence bone-implant-contact; dBIC) was significantly higher for Groups 2 and 3 compared to Group 1 (p < 0.05). The amount of newly formed bone (BATA) and NBH was not influenced by surface type. However, moderately rough surfaces demonstrated significantly superior levels of osseointegration (dBIC) and coronal bone apposition (fBIC) in the dehiscence defect compared to the NGA surface at 2 and 8 weeks. For this type of study, clinical trial registration is not required. This study was conducted at the Biomedical Department of Lund University (Lund, Sweden) and approved by the local Ethics Committee of the University (M-192-14).

Does alveolar ridge preservation reduce the need for sinus floor elevation: A comparative study to spontaneous healing.

In cases of atrophy in the maxillary posterior region, characterized by reduced vertical bone volume, implant placement becomes challenging. Augmentation procedures like sinus lifts are often needed to address insufficient bone volume. This study aims to explore if alveolar ridge preservation, using a bovine bone substitute and a porcine collagen membrane, significantly decreases the need for sinus lifts compared to natural wound healing after tooth extraction. In this comparative clinical study, 40 patients requiring a total of 53 extractions were assigned to one of the following groups: a test group with bovine bone substitute material (Straumann® XenoFlex) and a porcine collagen membrane (Jason® membrane), or a control group with spontaneous socket healing. After 6 months, digital volume tomography was performed for implant planning. For seven patients from the control group (n = 22 extracted sites) sinus lift augmentations were performed while only four sinus lift procedures were performed in the test group (n = 31 extracted sites), indicating a higher need for sinus augmentation procedures in the control group, however not statistically different on a p value of 0.05 (p = 0.168). In the control group, the mean value of the radiographically measured bone height (mesial and distal) was 11.13 ± 2.12 mm preoperatively before tooth extraction, while it was 11.3 ± 2.17 mm postoperatively after implant placement. In contrast, the mean value in the test group was 11.78 ± 3.09 mm preoperatively and 11.92 ± 2.79 mm postoperatively. Statistical analysis revealed no significant difference between the two groups (odds ratio 0.32; 95% CI: 0.08, 1.26; p = 0.951). The implant survival rate in the control group was 100%, compared to 96.77% in the test group. Within the limits of this study, the use of bovine bone substitute and a porcine resorbable membrane after tooth extraction in the posterior maxilla seems to reduce the need for sinus augmentation in comparison to spontaneous healing although the difference was not statistically significant. Additionally, the Alveolar Ridge Preservation in the test group made external sinus floor elevation unnecessary compared to the control group. The change in radiographically measured bone height pre- and postoperatively showed no significant difference between the two groups.

Treatment of Complex Multiple Lesions in the Knee With MACI (Autologous Cultured Chondrocytes on Porcine Collagen Membrane)

Background: Multiple chondral lesions in the knee are difficult to manage. A few treatment options are available. Considering the number of lesions, size, location, and total surface area, the autologous cultured chondrocytes on porcine collagen membrane (MACI) technique can effectively treat multiple defects simultaneously. Indications: The MACI procedure is indicated for multiple chondral lesions in the knee with large surface areas when other technologies are hard to implement or lack sufficient follow-up. Technique Description: The chondral defects are debrided to subchondral bone with vertical walls. Concomitant procedures are to be completed before MACI implantation. Each defect is treated as an isolated lesion. Irregular and uncontained lesions require a unique approach. A single membrane can treat multiple lesions; however, careful presurgery analysis is necessary to analyze the requirement of an additional membrane. Results: The MACI technique for multiple lesions in the knee has a good response rate and high satisfaction scores over mid- to long-term follow-up. Discussion/Conclusions: Multiple chondral lesions of the knee can effectively be treated with MACI, providing patients with additional improved quality of life, increasing level of function, and possibly delaying total knee arthroplasty procedures. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Healing patterns of alveolar bone following ridge preservation procedures.

Examine the histomorphometric bone composition, following alveolar ridge preservation techniques and unassisted socket healing. Forty-two patients (42) requiring a single rooted tooth extraction were randomly allocated into three groups (n = 14 per group): Group 1: Guided Bone Regeneration (GBR) using deproteinised bovine bone mineral (DBBM) and a porcine collagen membrane; Group 2: Socket Seal (SS) technique using DBBM and a porcine collagen matrix; Group 3: Unassisted socket healing (Control). Trephined bone biopsies were harvested following a 4-month healing period. Forty-two samples underwent Back-Scattered Electrons -Scanning Electron Microscopy (BSE-SEM) imaging, with 15 samples examined using Xray Micro-Tomography (XMT) (n = 6 for each GBR/SS and n = 3 Control). Images were analysed to determine the percentage (%) of connective tissue, new bone formation, residual DBBM particles and direct bone to DBBM particle contact (osseointegration). BSE-SEM analysis demonstrated that new bone formation was higher in the Control (45.89% ± 11.48) compared to both GBR (22.12% ± 12.7/p < .004) and SS (27.62% ± 17.76/p < .005) groups. The connective tissue percentage in GBR (49.72% ± 9), SS (47.81% ± 12.57) and Control (47.81% ± 12.57) groups was similar. GBR (28.17% ± 16.64) and SS (24.37% ± 18.61) groups had similar levels of residual DBBM particles. XMT volumetric analysis indicated a lower level of bone and DBBM particles in all test groups, when matched to the BSE-SEM area measurements. Osseointegration levels (DBBM graft and bone) were recorded at 35.66% (± 9.8) for GBR and 31.18% (± 19.38) for SS. GBR and SS ARP techniques presented with less bone formation when compared to unassisted healing. GBR had more direct contact/osseointegration between the DBBM particles and newly formed bone.

Treatment of periodontal osseous defect with bio-oss xenograft and biodegradable IGF fibers: A case report

Osseous defect caused due to periodontitis needed to be repaired or regenerated to avoid tooth loss. Bio-oss is made up of 10% porcine collagen and can induce osteoblastic differentiation due to its volumetric stability and out standing osteoconductive properties. Application of growth factors in regenerative procedures have helped to maintain the scaffold and induce several cellular processes. The biodegradable fibers incorporated with IGF growth factor has strong effect on PDL fibroblasts, mitogenesis, and protein synthesis which promotes osteogenesis and cementogenesis. A patient having grade II furcation and intrabony defect was treated and evaluated after 12 months with biodegradable fibers infused with insulin like growth factor and bio oss xeno graft irt 36. Treated site responded well to the use of the bovine bone mineral with good tissue response and an improvement and there was an overall mean probing pocket reduction in the deepest site of osseous defects. The clinical parameters assessed are plaque index, bleeding on brobing, pocket probing depth, clinical attachment level, glickman’s furcation index and RVG at baseline, 6 and 12 months post operatively. Both the bone grafts resulted in better regeneration when compared to base line and 12 months.Bio oss (bovine bone mineral) and biodegradable fibres infused with insulin like growth factor materials are of considerable promise for regeneration with better clinical and radiographic outcomes.

Alveolar Ridge Preservation Using a Novel Species-Specific Collagen-Enriched Deproteinized Bovine Bone Mineral: Histological Evaluation of a Prospective Case Series.

In recent years, the significance of maintaining the alveolar ridge following tooth extractions has markedly increased. Alveolar ridge preservation (ARP) is a commonly utilized technique and a variety of bone substitute materials and biologics are applied in different combinations. For this purpose, a histological evaluation and the clinical necessity of subsequent guided bone regeneration (GBR) in delayed implantations were investigated in a prospective case series after ARP with a novel deproteinized bovine bone material (95%) in combination with a species-specific collagen (5%) (C-DBBM). Notably, block-form bone substitutes without porcine collagen are limited, and moreover, the availability of histological data on this material remains limited. Ten patients, each scheduled for tooth extraction and desiring future implantation, were included in this study. Following tooth extraction, ARP was performed using a block form of C-DBBM in conjunction with a double-folded bovine cross-linked collagen membrane (xCM). This membrane was openly exposed to the oral cavity and secured using a crisscross suture. After a healing period ranging from 130 to 319 days, guided trephine drilling was performed for implant insertion utilizing static computer-aided implant surgery (s-CAIS). Cores harvested from the area previously treated with ARP were histologically processed and examined. Guided bone regeneration (GBR) was not necessary for any of the implantations. Histological examination revealed the development of a lattice of cancellous bone trabeculae through appositional membranous osteogenesis at various stages surrounding C-DBBM granules as well as larger spongy or compact ossicles with minimal remnants. The clinical follow-up period ranged from 2.5 to 4.5 years, during which no biological or technical complications occurred. Within the limitations of this prospective case series, it can be concluded that ARP using this novel C-DBBM in combination with a bovine xCM could be a treatment option to avoid the need for subsequent GBR in delayed implantations with the opportunity of a bovine species-specific biomaterial chain.

Efficacy and Safety of Fillers for the Treatment of Nasolabial Folds: A Network meta-Analysis of Randomized Controlled Trials.

Nasolabial fold formation is increasingly becoming a cause of concern for many people. However, no network meta-analysis has compared the efficacy of different fillers in treating nasolabial folds. This network meta-analysis simultaneously compared the efficacy and safety of various fillers. We included randomized controlled trials (RCTs) that used fillers to treat nasolabial folds. We extracted data of Wrinkle Severity Rating Scale (WSRS), Global Esthetic Improvement Scale (GAIS, investigator) scores, GAIS scores (self-reported) and adverse events. We included 13 RCTs. WSRS scores at 6 months were higher in patients receiving HA than those receiving poly (L-lactic acid) (mean difference [MD] 0.630, 95% confidence interval [CI] 0.275, 0.985) but significantly lower in patients receiving HA than in those receiving bovine collagen (MD - 0.580, 95% CI - 0.777, - 0.383) and porcine collagen (MD - 0.525, 95% CI - 0.790, - 0.260). Regarding adverse events, HA was significantly less likely to cause nodule formation compared with bovine collagen (RR 0.593, 95% CI 0.438, 0.803). HA is a safe filler for correcting nasolabial folds, and poly (L-lactic acid) showed potential in treating nasolabial folds. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Exploration of hypoglycemic peptides from porcine collagen based on network pharmacology and molecular docking.

In recent years, the extraction of hypoglycemic peptides from food proteins has gained increasing attention. Neuropeptides, hormone peptides, antimicrobial peptides, immune peptides, antioxidant peptides, hypoglycemic peptides and antihypertensive peptides have become research hotspots. In this study, bioinformatic methods were used to screen and predict the properties of pig collagen-derived hypoglycemic peptides, and their inhibitory effects on α-glucosidase were determined in vitro. Two peptides (RL and NWYR) were found to exhibit good water solubility, adequate ADMET (absorption, distribution, metabolism, elimination, and toxicity) properties, potentially high biological activity, and non-toxic. After synthesizing these peptides, NWYR showed the best inhibitory effect on α-glucosidase with IC50 = 0.200±0.040 mg/mL, and it can regulate a variety of biological processes, play a variety of molecular functions in different cellular components, and play a hypoglycemic role by participating in diabetic cardiomyopathy and IL-17 signaling pathway. Molecular docking results showed that NWYR had the best binding effect with the core target DPP4 (4n8d), with binding energy of -8.8 kcal/mol. NWYR mainly bonded with the target protein through hydrogen bonding, and bound with various amino acid residues such as Asp-729, Gln-731, Leu-765, etc., thus affecting the role of the target in each pathway. It is the best core target for adjuvant treatment of T2DM. In short, NWYR has the potential to reduce type 2 diabetes, providing a basis for further research or food applications as well as improved utilization of pig by-products. However, in subsequent studies, it is necessary to further verify the hypoglycemic ability of porcine collagen active peptide (NWYR), and explore the hypoglycemic mechanism of NWYR from multiple perspectives such as key target genes, protein expression levels and differences in metabolites in animal models of hyperglycemia, which will provide further theoretical support for its improvement in the treatment of T2DM.

Evaluation of Porcine Collagen Membranes Used with Guided Bone Regeneration for Critical Defects: A Histological, Histomorphometric, Immunohistochemical, and Inflammatory Profile Analysis.

The objective of this study was to compare the effectiveness of two porcine collagen membranes of different origin used for guided bone regeneration procedures. Resorbable collagen membrane from porcine dermis (Bio-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) and resorbable collagen membrane from porcine pericardium (Jason, Institut Straumann AG, Peter Merian-Weg, Switzerland) were evaluated; histological, histometric, immunohistochemical, and inflammatory profile analyses were performed. The study was carried out on critical defects created in the calvaria of 72 rats (Rattus norvegicus albinus, Wistar variety) divided into three groups: coagulum group (Co), porcine pericardium group (JS), and porcine collagen group (BG). The defects were filled with clot, over which the membranes were placed. The animals were euthanized 7, 15, 30, and 60 days after surgery. The Shapiro-Wilk test was used to assess data distribution. Analysis of variance (ANOVA) and the Bonferroni multiple comparison test were used to compare the differences across the mean values of the variables. Nonparametric tests, Mann-Whitney and Wilcoxon W, were used for the quantitative analysis of the inflammatory profile. A significance level of 5% (p < 0.05) was adopted with a confidence interval of 95%. SPSS software version 2.0 was used. A total of 1,008 analyses were performed on 288 histological slides. It was noted that both types of collagen membranes used in this study were effective for the guided bone regeneration procedure, with a greater proportion and thickness of bone formation among recipients of the BG (735 points, p = 0.021). This membrane also had greater permeability (62.25). The animals in the JS group, which received the porcine pericardial membrane, showed early and accelerated bone formation from early bone tissue, milder osteopontin and osteocalcin levels, and greater inflammatory reaction (86.4). The collagen membrane from porcine dermis demonstrated a more orderly and physiological repair process, while the porcine pericardial membrane presented a more accelerated repair process that did not remain constant over time.

Assessment of Tilapia Skin Collagen for Biomedical Research Applications in Comparison with Mammalian Collagen.

Collagen is an important material for biomedical research, but using mammalian tissue-derived collagen carries the risk of zoonotic disease transmission. Marine organisms, such as farmed tilapia, have emerged as a safe alternative source of collagen for biomedical research. However, the tilapia collagen products for biomedical research are rare, and their biological functions remain largely unexamined. In this study, we characterized a commercial tilapia skin collagen using SDS-PAGE and fibril formation assays and evaluated its effects on skin fibroblast adhesion, proliferation, and migration, comparing it with commercial collagen from rat tails, porcine skin, and bovine skin. The results showed that tilapia skin collagen is a type I collagen, similar to rat tail collagen, and has a faster fibril formation rate and better-promoting effects on cell migration than porcine and bovine skin collagen. We also confirmed its application in a 3D culture for kidney cells' spherical cyst formation, fibroblast-induced gel contraction, and tumor spheroid interfacial invasion. Furthermore, we demonstrated that the freeze-dried tilapia skin collagen scaffold improved wound closure in a mouse excisional wound model, similar to commercial porcine or bovine collagen wound dressings. In conclusion, tilapia skin collagen is an ideal biomaterial for biomedical research.

All-Arthroscopic Matrix-Associated Autologous Chondrocyte Implantation for a Trochlear Defect

Matrix-associated autologous chondrocyte implantation (MACI) is a 2-step technique designed to treat symptomatic full-thickness articular cartilage defects of the knee. In this technique article, MACI (autologous cultured chondrocytes on porcine collagen membrane) is used to treat a femoral trochlear defect of the knee. Treating a defect with this technique leads to improved clinical outcomes by restoring the native chondral surface architecture and biomechanics of the knee. In addition, it has the potential to prevent or delay further progressive degeneration of the joint. It is a 2-stage procedure consisting of an initial arthroscopic cartilage biopsy, followed by 4 to 6 weeks of in vitro chondrocyte expansion and, finally, re-implantation. We recommend performing the MACI procedure arthroscopically for the second stage to treat a femoral trochlear defect. During the second surgical procedure, we examine and prepare the recipient site, followed by graft introduction in an all-arthroscopic manner via dry scoping, secured by a thin layer of fibrin glue.

Safety and Efficacy of Mucograft Porcine Collagen Bioengineered Acellular Dermal Matrix as a Spacer Graft in Lower Eyelid Elevation Surgery.

Recent regulatory changes have limited the access to a widely used commercially available bioengineered acellular dermal matrix (BADM) product as a spacer graft in the surgical correction of lower eyelid retraction. We report our off-label usage of Mucograft, a porcine BADM, as an alternative BADM. A retrospective review was conducted of patients undergoing bilateral lower lid surgery with Mucograft (12 eyes) at a single institution. For the six patients, there was a mean lower lid elevation of 1.93 mm, without any serious complications. There was greater elevation of the lower lid position for the Mucograft group compared with four septo-retractor control patients (1.93 versus 0.94mm, P = 0.008). Mucograft performed satisfactorily, and further investigation is warranted regarding its longer-term safety and efficacy.

MACI Sandwich Technique With Autologous Bone Graft

Background: Osteochondral lesions of the knee are difficult to manage. Such lesions can be effectively treated with the matrix-induced autologous chondrocyte implantation (MACI) “sandwich” technique using autologous chondrocytes on porcine collagen membrane in conjuction with autologous cancellous bone grafting (ABG). Few studies have examined this technique to restore the osteochondral unit. Indications: The MACI “Sandwich” procedure is indicated when osteochondral lesions are larger than 2 cm2 in size and deeper than 8 to 10 mm, with symptoms consistent with the location of the lesion. Technique Description: The chondral defect is radically debrided back to healthy bone and cartilage tissue. The base of the bony cavity is drilled to enhance the vascular supply and promote healing. Next, the bony cavity is prepared to slightly undermine the subchondral bone surface around the articular margins, with the depth of the cavity wider than the opening, similar to a dental amalgam. The autologous cancellous bone is subsequently morselized and impacted up to the level of the native subchondral bone plate. The first MACI membrane with the cells facing up is placed directly onto the bone graft site and compressed with a neural patty. The neural patty is removed, and the second MACI membrane is then placed with the cells facing down. The edges are then micro-sutured to ensure stability. Results: The “sandwich” technique has superior survival rates compared with autologous bone grafting alone, with patients reporting decreased pain, improved function, and high satisfaction scores over a mid-term to long-term follow-up. Discussion/Conclusion: The MACI “sandwich” technique is an effective surgical intervention to restore the osteochondral unit and preserve the patient's native knee joint. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

X-Ray Visible Protein Scaffolds by Bulk Iodination.

Protein-based biomaterial use is expanding within medicine, together with the demand to visualize their placement and behavior in vivo. However, current medical imaging techniques struggle to differentiate between protein-based implants and surrounding tissue. Here a fast, simple, and translational solution for tracking transplanted protein-based scaffolds is presented using X-ray CT-facilitating long-term, non-invasive, and high-resolution imaging. X-ray visible scaffolds are engineered by selectively iodinating tyrosine residues under mild conditions using readily available reagents. To illustrate translatability, a clinically approved hernia repair mesh (based on decellularized porcine dermis) is labeled, preserving morphological and mechanical properties. In a mouse model of mesh implantation, implants retain marked X-ray contrast up to 3 months, together with an unchanged degradation rate and inflammatory response. The technique's compatibility is demonstrated with a range of therapeutically relevant protein formats including bovine, porcine, and jellyfish collagen, as well as silk sutures, enabling a wide range of surgical and regenerative medicine uses. This solution tackles the challenge of visualizing implanted protein-based biomaterials, which conventional imaging methods fail to differentiate from endogenous tissue. This will address previously unanswered questions regarding the accuracy of implantation, degradation rate, migration, and structural integrity, thereby accelerating optimization and safe translation of therapeutic biomaterials.

Nano-calcium incorporated piscean collagen scaffolds: potential wound dressing material

BackgroundCollagen proteins extracted from piscean sources are alternatives to bovine and porcine collagen because of their abundance, low price, and skin compatibility and are being explored as suitable wound dressing materials. Intracellular calcium ions are crucial for wound healing, and studies have shown that calcium ion supplementation via an external medium is equally beneficial for speedy recovery. This study explores the wound healing potential of dressing materials that encompass the benefits of nano-calcium and piscean collagen. Nano-calcium sulphate (NCS)-integrated scaffolds were prepared with 100 ppm of NCS and varying concentrations of piscean collagen and HPMC E15 LV. The thickness, tensile strength, folding endurance, pH, expansion profile, and moisture vapour transmission properties of the scaffolds were determined. An in vitro scratch assay and an excision rat wound model were employed to evaluate the wound healing properties of the scaffolds.ResultsThe NCS particles had a mean particle size of 220.7 nm. The scaffolds demonstrated an acceptable thickness, mechanical strength, and flexibility. The scratch assay results revealed that at the end of 24 h of the study, there was an increased wound closure rate with collagen scaffolds in contrast to the control group. In the vivo wound healing studies, formulation CS6 showed 100.0% healing on day 12 as compared to other formulations.ConclusionsWounds treated with scaffolds contracted faster than those treated with a commercial collagen dressing and the control group. The current study thus demonstrates the wound healing ability of nano-calcium sulphate-incorporated piscean collagen scaffolds.