Evaluation of the tissue repair process and immunomodulatory action of Platelet-Rich Plasma (PRP) in the treatment of abdominal stretch marks.

The aims of this study were to characterize and to compare the structural alterations of collagen and elastic fibers in the abdominal stretch marks of patients submitted to intralesional and per quadrant (region close to stretch marks) Platelet-Rich Plasma (PRP) treatment, as well as, to establish the possible mechanisms of action of this treatment involving toll-like receptors (TLRs) signaling pathways and growth factors. Incisional biopsies were collected from abdominal stretch marks with a 2 mm diameter punch in female patients, at the beginning of treatment, after 6 and 12 weeks of treatment, and submitted to morphological analyzes of elastic and collagen fibers, and immunohistochemistry for TLRs signaling pathways and growth factors. Our results demonstrated PRP per quadrant treatment was most effective in reducing the area of the abdominal stretch marks, with consequent stimulation of the synthesis and remodeling of collagen and elastic fibers. Also, PRP per quadrant treatment promoted an increase in TLR2 and TLR4 immunoreactivities, with consequent increase in TNF-α, VEGF and IGF-1. Based on the current findings, PRP constitutes a promising therapeutic approach in patients with stretch marks, since it promoted modulation of inflammatory cytokines and growth factors, with consequent remodeling of extracellular matrix, culminating with tissue improvement.

Using umbilical cord blood as a source of paediatric packed red blood cells: Processing and quality control.

BACKGROUND AND OBJECTIVES: Umbilical cord blood (UCB) has been used as a source of red blood cells (RBCs) for neonatal/paediatric transfusion purposes. This study adopted two different procedures to obtain umbilical RBC (U-RBC) to compare its quality control parameters to those of fractionated adult RBC (A-RBC), for paediatric purposes. MATERIALS AND METHODS: UCB units (24) were filtered and processed based on two different methods, namely, conventional/manual (P1;n12) and automatic (P2;n12). They were compared to five fractionated A-RBCs. U-RBC and A-RBC were stored for 14 days and had their haematological, biochemical, haemolytic and microbiological parameters analysed at D1, D7 and D14. Cytokines and growth factors (GFs) in residual U-RBC plasma were measured. RESULTS: Mean volume of processed U-RBC units was 45 mL for P1 and 39 mL for P2; the mean haematocrit level reached 57% for P1 and 59% for P2. A-RBC recorded a mean volume of 44 mL. Haematologic and biochemical parameters analysed in U-RBC and A-RBC presented similar behaviours during storage time, except for parameter values, which differed between them. Pro-inflammatory and immunomodulatory cytokines, as well as GFs, were higher in U-RBC residual plasma than in that A-RBC. CONCLUSION: UCB can be processed into RBC based on either manual or automated protocols. U-RBC units met the referenced quality parameters defined for A-RBC. Some features, mainly the biochemical ones, should be further investigated to help improve quality parameters, with emphasis on differences found in, and particularities of, this material and on recipients of this new transfusion practice.

Full Diabetic Foot Ulcer Healing and Pain Relief Based on Platelet-Rich-Plasma gel Formulation Treatment and the Involved Pathways.

Diabetic foot ulcer is a severe Diabetic Mellitus-associated complication. It is induced by poor glycemic control, which leads to peripheral neuropathy and vascular diseases. Platelet-rich plasma could be beneficial for healing processes due to its active biomolecules that promotes immunomodulation, angiogenesis, cell proliferation and analgesia.

Delayed onset, immunomodulation, and lifespan improvement of SOD1G93A mice after intravenous injection of human mesenchymal stem cells derived from adipose tissue.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the selective and progressive loss of motor neurons from the spinal cord, brain stem, and motor cortex. Although the hallmark of ALS is motor neuron degeneration, astrocytes, microglia, and T cells actively participate. Pharmacological treatment with riluzole has little effect on the lifespan of the patient. Thus, the development of new therapeutic strategies is of utmost importance. The objective of this study was to verify whether human mesenchymal stem cells (hMSCs) from adipose tissue have therapeutic potential in SOD1G93A transgenic mice. The treatment was carried out in the asymptomatic phase of the disease (10th week) by a single systemic application of ad-hMSCs (1 ×105 cells). The animals were sacrificed at the 14th week (the initial stage of symptoms) or the end-stage (ES) of the disease. The lumbar spinal cords were dissected and processed for Nissl staining (neuronal survival), immunohistochemistry (gliosis and synaptic preservation), and gene transcript expression (qRT-PCR). Behavioral analyses considering the onset of disease and its progression, neurological score, body weight, and motor control (rotarod test) started on the 10th week and were performed every three days until the ES of the disease. The results revealed that treatment with ad-hMSCs promoted greater neuronal survival (44%) than vehicle treatment. However, no effect was seen at the ES of the disease. Better structural preservation of the ventral horn in animals treated with ad-hMSCs was observed, together with decreased gliosis and greater synapse protection. In line with this, we found that the transcript levels of Hgf1 were upregulated in ad-hMSCs-treated mice. These results corroborate the behavioral data showing that ad-hMSCs had delayed motor deficits and reduced weight loss compared to vehicle animals. Additionally, cell therapy delayed the course of the disease and significantly improved survival by 20 days. Overall, our results indicate that treatment with ad-hMSCs has beneficial effects, enhancing neuronal survival and promoting a less degenerative neuronal microenvironment. Thus, this may be a potential therapy to improve the quality of life and to extend the lifespan of ALS patients.

Poly (L-Lactic Acid) Cell-Laden Scaffolds Applied on Swine Model of Tracheal Fistula.

INTRODUCTION: Tracheal fistula (TF) treatments may involve temporary orthosis and further ablative procedures, which can lead to infection. Thus, TF requires other therapy alternatives development. The hypothesis of this work was to demonstrate the feasibility of a tissue-engineered alternative for small TF in a preclinical model. Also, its association with suture filaments enriched with adipose tissue-derived mesenchymal stromal stem cells (AT-MSCs) was assessed to determine whether it could optimize the regenerative process. METHODS: Poly (L-Lactic acid) (PLLA) membranes were manufactured by electrospinning and had morphology analyzed by scanning electron microscopy. AT-MSCs were cultured in these scaffolds and in vitro assays were performed (cytotoxicity, cellular adhesion, and viability). Subsequently, these cellular constructs were implanted in an animal small TF model. The association with suture filaments containing attached AT-MSCs was present in one animal group. After 30 d, animals were sacrificed and regenerative potential was evaluated, mainly related to the extracellular matrix remodeling, by performing histopathological (Hematoxylin-Eosin and trichrome Masson) and immunohistochemistry (Collagen I/II/III, matrix metalloproteinases-2, matrix metalloproteinases-9, vascular endothelial growth factor, and interleukin-10) analyses. RESULTS: PLLA membranes presented porous fibers, randomly oriented. In vitro assays results showed that AT-MSCs attached were viable and maintained an active metabolism. Swine implanted with AT-MSCs attached to membranes and suture filaments showed aligned collagen fibers and a better regenerative progress in 30 d. CONCLUSIONS: PLLA membranes with AT-MSCs attached were useful to the extracellular matrix restoration and have a high potential for small TF treatment. Also, their association with suture filaments enriched with AT-MSCs was advantageous.

Diagnosis, Prognosis and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors.

Mast cell tumors (MCTs) are hematopoietic neoplasms composed of mast cells. It is highly common in dogs and is extremely important in the veterinary oncology field. It represents the third most common tumor subtype, and is the most common malignant skin tumor in dogs, corresponding to 11% of skin cancer cases. The objective of this critical review was to present the report of the 2nd Consensus meeting on the Diagnosis, Prognosis, and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors, which was organized by the Brazilian Association of Veterinary Oncology (ABROVET) in August 2021. The most recent information on cutaneous and subcutaneous mast cell tumors in dogs is presented and discussed.

Association of acidosis with coagulopathy and transfusion requirements in liver transplantation.

The relationship between acidosis and coagulopathy has long been described in vitro and in trauma patients, but not yet in orthotopic liver transplantation (OLT). The association of metabolic acidosis with coagulopathy and with transfusion requirements was evaluated in patients submitted to OLT. Changes in acid-base and coagulation parameters were analyzed by repeated measures. Regression analyses [adjusted for sex, age, model for end stage liver disease (MELD) score, and baseline values of hemoglobin, fibrinogen, international normalized ratio, platelets] determined the association of acid-base parameters with coagulation markers and transfusion requirement. We included 95 patients, 66% were male, 49.5% of the patients had hepatocellular carcinoma and the mean MELD score was 20.4 (SD 8.9). The values of all the coagulation and acid-base parameters significantly changed during OLT, particularly in the reperfusion phase. After adjustments for baseline parameters, the decrease in pH and base excess (BE) values were associated with a decrease in fibrinogen levels (mean decrease of fibrinogen level = 14.88 mg/dL per 0.1 unit reduction of pH values and 3.6 mg/dL per 1 mmol/L reduction of BE levels) and an increase in red blood cells transfusion (2.16 units of RBC per 0.1 unit reduction of pH and 0.38 units of RBC per 1 mmol/L reduction of BE levels). Among multiple factors potentially associated with adverse outcomes, decreasing pH levels were independently associated with the length of hospitalization but not with in-hospital mortality. Metabolic acidosis is independently associated with decreased fibrinogen levels and increased intraoperative transfusion requirement during OLT. Awareness of that association may improve treatment strategies to reduce intraoperative bleeding risk in OLT.

Neuroprotection and gliosis attenuation by intravenous application of human mesenchymal stem cells (hMSC) following ventral root crush in mice.

Rupture and stretching of spinal roots are common incidents that take place in high-energy accidents. The proximal axotomy of motoneurons by crushing of ventral roots is directly related to the degeneration of half of the lesioned population within the first two weeks. Moreover, only a small percentage of surviving motoneurons can successfully achieve regeneration after such a proximal lesion, and new treatments are necessary to improve this scenario. In this sense, mesenchymal stem cells (MSC) are of great interest once they secrete a broad spectrum of bioactive molecules that are immunomodulatory and can restore the environment after a lesion. The present work aimed at studying the effects of human mesenchymal stem cells (hMSC) therapy after ventral root crush (VRC) in mice. We evaluated motoneuron survival, glial reaction, and synapse preservation at the ventral horn. For this purpose, C57BL/6 J were submitted to a crush procedure of L4 to L6 ventral roots and treated with a single intravenous injection of adipose-derived hMSC. Evaluation of the results was carried out at 7, 14, and 28 days after injury. Analysis of motoneuron survival and astrogliosis showed that hMSC treatment resulted in higher motoneuron preservation (motoneuron survival ipsi/contralateral ratio: VRC group = 53%, VRC + hMSC group = 66%; p < 0.01), combined with reduction of astrogliosis (ipsi/contralateral GFAP immunolabeling: VRC group = 470%, VRC + hMSC group = 250%; p < 0.001). The morphological classification and Sholl analysis of microglial activation revealed that hMSC treatment reduced type V and increased type II profiles, indicating an enhancement of surveying over activated microglial cells. The glial reactivity modulation directly influenced synaptic inputs in apposition to axotomized motoneurons. In the hMSC-treated group, synaptic maintenance was increased (ipsi/contralateral synaptophysin immunolabeling: VRC group = 53%, VRC + hMSC group = 64%; p < 0.05). Overall, the present data show that intravenous injection of hMSC has neuroprotective and anti-inflammatory effects, decreasing reactive astrogliosis, and microglial reaction. Also, such cell therapy results in motoneuron preservation, combined with significant maintenance of spinal cord circuits, in particular those related to the ventral horn.

Spinal Reflex Recovery after Dorsal Rhizotomy and Repair with Platelet-Rich Plasma (PRP) Gel Combined with Bioengineered Human Embryonic Stem Cells (hESCs).

Dorsal root rhizotomy (DRZ) is currently considered an untreatable injury, resulting in the loss of sensitive function and usually leading to neuropathic pain. In this context, we recently proposed a new surgical approach to treat DRZ that uses platelet-rich plasma (PRP) gel to restore the spinal reflex. Success was correlated with the reentry of primary afferents into the spinal cord. Here, aiming to enhance previous results, cell therapy with bioengineered human embryonic stem cells (hESCs) to overexpress fibroblast growth factor 2 (FGF2) was combined with PRP. For these experiments, adult female rats were submitted to a unilateral rhizotomy of the lumbar spinal dorsal roots, which was followed by root repair with PRP gel with or without bioengineered hESCs. One week after DRZ, the spinal cords were processed to evaluate changes in the glial response (GFAP and Iba-1) and excitatory synaptic circuits (VGLUT1) by immunofluorescence. Eight weeks postsurgery, the lumbar intumescences were processed for analysis of the repaired microenvironment by transmission electron microscopy. Spinal reflex recovery was evaluated by the electronic Von Frey method for eight weeks. The transcript levels for human FGF2 were over 37-fold higher in the induced hESCs than in the noninduced and the wildtype counterparts. Altogether, the results indicate that the combination of hESCs with PRP gel promoted substantial and prominent axonal regeneration processes after DRZ. Thus, the repair of dorsal roots, if done appropriately, may be considered an approach to regain sensory-motor function after dorsal root axotomy.

Hyaluronic acid and fibrin from L-PRP form semi-IPNs with tunable properties suitable for use in regenerative medicine.

Autologous leukocyte- and platelet-rich plasma (L-PRP) combined with hyaluronic acid (HA) has been widely used in local applications for cartilage and bone regeneration. The association between L-PRP and HA confers structural and rheological changes that differ among individual biomaterials but has not been investigated. Therefore, the standardization and characterization of L-PRP-HA are important to consider when comparing performance results to improve future clinical applications. To this end, we prepared semi-interpenetrating polymer networks (semi-IPNs) of L-PRP and HA and characterized their polymerization kinetics, morphology, swelling ratio, stability and rheological behavior, which we found to be tunable according to the HA molar mass (MM). Mesenchymal stem cells derived from human adipose tissue (h-AdMSCs) seeded in the semi-IPNs had superior viability and chondrogenesis and osteogenesis capabilities compared to the viability and capabilities of fibrin. We have demonstrated that the preparation of the semi-IPNs under controlled mixing ensured the formation of cell-friendly hydrogels rich in soluble factors and with tunable properties according to the HA MM, rendering them suitable for clinical applications in regenerative medicine.

What is the potential use of platelet-rich-plasma (PRP) in cancer treatment? A mini review.

Platelet-rich-plasma (PRP) is an autologous human platelet concentrate extracted from plasma. PRP has been investigated in order to be used in many fields, with emphasis on the musculoskeletal field applied to sports injuries, as well as on other medical fields such as cardiac surgery, gynecology, pediatric surgery, urology, ophthalmology and plastic surgery. Cancer treatment is another important field where PRP should be investigated; thus, it is important validating PRP preparation protocols to be used in clinical research. Many protocols should be revised since, overall, most studies do not provide necessary information to allow them to be multiplied or replicated. The current review focuses on several topics about cancer, mainly on innovative studies about PRP use as a feasible therapeutic alternative to treat bladder cancer - a field where it could play a key role. Relevant aspects such as platelets' contribution to immune regulation and the supportive role they play in innate and adaptive immune functions are also addressed. Another important topic reviewed in the current study refers to inflammatory process regulation associated with cancer and thrombosis sites, which indicated that tumor-induced platelet activation could be used as an important therapeutic target in the future. New aspects concerning nitric oxide's ability to restrain platelet adhesion and aggregation in order to slow metastasis progress in cancer patients provide an important advantage in cancer treatment. Finally, the current review has pointed out perspectives and the main concerns about, and possibilities of, PRP use in cancer treatment.

Nanostructured platelet-rich plasma: state of art in dental treatments / Plasma-rico em plaquetas nanoestruturado: estado da arte nos tratamentos dentais

Objectives: Reviewing information available about platelet-rich plasma (PRP) applied to dental treatments, introducing the general concept of PRP, as well as analyzing actual data about, and challenges faced by, the dental field. Data & sources: The current study analyzed the most informative publications about PRP application available in this field and gathered the maximum information about it as possible. Conclusions: PRP use, either alone or in association with other biomaterials, can significantly favor different fields such as tissue engineering, since it is an innovative technique that attracts the interest of clinicians and basic scientists. However, it is necessary conducting better designed and controlled experiments to enable successful tissue healing based on PRP use. Clinical significance: The current review can be used by clinicians as source of information about the actual rules and protocols adopted in the herein addressed field, besides providing specific examples of such applications. (AU)

Objetivos: Revisar as informações disponíveis sobre o plasma-rico em plaquetas (PRP) aplicado a tratamentos odontológicos, introduzir o conceito geral de PRP e analisar dados reais sobre os desafios enfrentados pelo campo odontológico. Dados e fontes: O presente estudo analisou as publicações mais informativas sobre a aplicação do PRP disponíveis neste campo e reuniu o máximo de informações possível. Conclusões: O uso do PRP, isoladamente ou em associação com outros biomateriais, pode favorecer significativamente diferentes campos, como a engenharia de tecidos, uma vez que é uma técnica inovadora que atrai o interesse de clínicos e cientistas básicos. No entanto, é necessário realizar experimentos mais bem projetados e controlados para permitir a cura bem-sucedida dos tecidos com base no uso do PRP. Significado clínico: A revisão atual pode ser usada pelos médicos como fonte de informações sobre as regras e protocolos atuais adotados no campo aqui tratado, além de fornecer exemplos específicos de tais aplicações.(AU)

Monitorização de células-tronco mesenquimais injetadas via retrobulbar próximas ao nervo óptico lesados de coelhos / Monitoring of stem cells from adipose tissue injected via retrobulbar next to previously injured optic nerve of rabbits

Resumo Objetivo: Verificar a presença das células-tronco mesenquimais (MSC) na área próxima ao nervo óptico de coelhos previamente lesado com álcool absoluto. Métodos: Os 12 coelhos da raça Nova Zelândia foram distribuídos em 2 lotes. Após sedação, cada olho do animal recebeu uma injeção retrobulbar de 1 ml de álcool absoluto em um dos olhos e de 1 ml de solução fisiológica 0,9% (SF) no olho contralateral. Após 15 dias deste procedimento inicial todos os olhos dos animais pertencentes ao lote A, receberam via retrobulbar, uma solução contendo MSC de tecido adiposo humano e previamente marcadas com Qdots,. Todos os olhos dos animais do lote B receberam solução PBS. Resultados: Após 15 dias desta última aplicação os animais foram sacrificados e as lâminas foram analisadas. A presença das MSC foi observada em 100% dos olhos dos animais do lote A. Conclusão: Os resultados sugerem que a marcação prévia das MSC com Qdots permitiu o acompanhamento das mesmas na região aplicada e em áreas mais internas do nervo óptico. A permanência de MSC após 15 dias de aplicação ao redor do nervo óptico sugere a viabilidade e possível participação das mesmas no processo de regeneração do tecido lesado. Nas condições deste estudo, a via de aplicação retrobulbar permitiu a mobilização das células tronco do local de aplicação até áreas centrais dos nervos ópticos nos animais do lote A, sugerindo que esta poderá ser uma via de acesso eficaz para as MSC no processo de regeneração de neuropatias ópticas.

Abstract Obtective: To verify the presence of mesenchymal stem cells (MSC) in the area close to the optic nerve of previously injured with absolute alcohol. Methods: Twelve New Zealand breed rabbits were divided into two groups, and after sedation, each eye of the animal received a retrobulbar injection of 1 ml of absolute ethanol in one eye, and 1 ml of physiological solution 0.9 % (PS) in the contralateral eye. After 15 days all eyes of animals belonging to group A, received via retrobulbar a solution containing MSCs from human adipose tissue (AT) and previously marked with Qdots, while all eyes of animals from group B received solution containing PBS. Results: The presence of MSC was observed in 100% of the eyes of the animals of group A and the more central areas near and into the optic nerve. Conclusion: The results suggest that the appointment of MSC with Qdots allowed their follow-up applied in the region and in the inner areas of the optic nerve. The MSC permanence after 15 days of application around the optic nerve suggests the feasibility and possible involvement of the same during the damaged tissue regeneration process. Under the conditions of this study, the route of retrobulbar application and the presence of the stem cells to the central areas of the optic nerves in animals of group A, suggests that this might be an effective approach for MSCs in regeneration process of optic neuropathies.

Association of Platelet-Rich Plasma and Auto-Crosslinked Hyaluronic Acid Microparticles: Approach for Orthopedic Application.

Platelet-rich plasma (PRP) associated with high molecular weight hyaluronic acid (HA) has been clinically used for tissue regeneration in orthopedics. Despite the recognized beneficial clinical outcomes (e.g., early pain control, improvement of patients' functional limitation and longer-term effectiveness compared to PRP and HA alone in mild and moderate osteoarthritis treatments), its use is still challenging and controversial due to lack of standardization of association practical protocols. Moreover, most studies neglect the matrix structure, that generates the ultimate properties of the association among platelets, fibrin network and the microparticles. In the present work, we aimed to analyze the influence of the PRP/HA association with a controlled matrix structure on the stability, rheological behavior, release of growth factors and in vitro proliferation of human adipose-derived mesenchymal cells (h-AdMSCs). The attenuation of the negative charge of HA was also evaluated. Pure PRP (P-PRP) (i.e., plasma enriched with platelets and poor in leukocytes) was prepared by centrifugation and activated with serum and calcium chloride (AP-PRP). Autocrosslinked hyaluronic acid (AHA) was prepared by organocatalyzed auto-esterification and structured in microparticles (MPAHA) by shearing. The attenuation of the negative charge of MPAHA was performed with chitosan (CHT) by polyelectrolyte complexation yielding MPAHA-CHT. The results showed that microparticles (MPs) have viscoelastic properties, extrusion force and swelling ratio appropriate for injectable applications. The association of AP-PRP with the controlled structure of MPAHA and MPAHA-CHT formed a matrix composed of platelets and of a fibrin network with fibers around 160 nm located preferably on the surface of the MPs with an average diameter of 250 µm. Moreover, AP-PRP/MPAHA and AP-PRP/MPAHA-CHT associations were non-toxic and supported controlled growth factor (PDGF-AB and TGF-ß1) release and in vitro proliferation of h-AdMSC with a similar pattern to that of AP-PRP alone. The best h-AdMSC proliferation was obtained with the AP-PRP/MPAHA-CHT75:25 indicating that the charge attenuation improved the cell proliferation. Thus, the association of AP-PRP with the controlled structure of HA can be a valuable approach for orthopedic applications.

Centrifugation Conditions in the L-PRP Preparation Affect Soluble Factors Release and Mesenchymal Stem Cell Proliferation in Fibrin Nanofibers.

Leukocyte and platelet-rich plasma (L-PRP) is an autologous product that when activated forms fibrin nanofibers, which are useful in regenerative medicine. As an important part of the preparation of L-PRP, the centrifugation parameters may affect the release of soluble factors that modulate the behavior of the cells in the nanofibers. In this study, we evaluated the influences of four different centrifugation conditions on the concentration of platelets and leukocytes in L-PRP and on the anabolic/catabolic balance of the nanofiber microenvironment. Human adipose-derived mesenchymal stem cells (h-AdMSCs) were seeded in the nanofibers, and their viability and growth were evaluated. L-PRPs prepared at 100× g and 100 + 400× g released higher levels of transforming growth factor (TGF)-ß1 and platelet-derived growth factor (PDGF)-BB due to the increased platelet concentration, while inflammatory cytokines interleukin (IL)-8 and tumor necrosis factor (TNF)-α were more significantly released from L-PRPs prepared via two centrifugation steps (100 + 400× g and 800 + 400× g) due to the increased concentration of leukocytes. Our results showed that with the exception of nanofibers formed from L-PRP prepared at 800 + 400× g, all other microenvironments were favorable for h-AdMSC proliferation. Here, we present a reproducible protocol for the standardization of L-PRP and fibrin nanofibers useful in clinical practices with known platelet/leukocyte ratios and in vitro evaluations that may predict in vivo results.

Reflex arc recovery after spinal cord dorsal root repair with platelet rich plasma (PRP).

Spinal dorsal roots can be affected by a wide range of lesions, leading to a significant loss of proprioceptive information transmission and greatly affecting motor behavior. In this context, the reimplantation of lesioned roots with platelet-rich plasma (PRP) may allow nerve regeneration. Therefore, the present study evaluated sensorimotor improvement following dorsal root rhizotomy and repair with PRP. For this purpose, female Lewis rats were subjected to unilateral rhizotomy (RZ) of the L4-L6 dorsal roots and divided into the following groups: (1) the unlesioned control group; (2) the group that underwent rhizotomy (RZ) without repair; and (3) the group that underwent RZ followed by root repair with PRP. PRP was obtained from human blood and characterized regarding platelet concentration, integrity, and viability. Reflex arc recovery was evaluated weekly for eight weeks by the electronic von Frey method. The spinal cords were processed 1 week postlesion to evaluate the in vivo gene expression of TNFα, TGF-ß, BDNF, GDNF, VEGF, NGF, IL-4, IL-6, IL-13 by qRT-PCR and eight weeks postlesion to evaluate changes in the glial response (GFAP and Iba-1) and excitatory synaptic circuits (VGLUT1) by immunofluorescence. The results indicated that PRP therapy partially restores the paw withdrawal reflex over time, indicating the reentry of primary afferents from the dorsal root ganglia into the spinal cord without exacerbating glial reactivity. Additionally, the analysis of mRNA levels showed that PRP therapy has immunomodulatory properties. Overall, the present data suggest that the repair of dorsal roots with PRP may be considered a promising approach to improve sensorimotor recovery following dorsal rhizotomy.

Effects of intravesical therapy with platelet-rich plasma (PRP) and Bacillus Calmette-Guérin (BCG) in non-muscle invasive bladder cancer.

This study describes the effects of a promising therapeutic alternative for non-muscle invasive bladder cancer (NMIBC) based on Bacillus Calmette-Guerin (BCG) intravesical immunotherapy combined with Platelet-rich plasma (PRP) in an animal model. Furthermore, this study describes the possible mechanisms of this therapeutic combination involving Toll-like Receptors (TLRs) 2 and 4 signaling pathways. NMIBC was induced by treating female Fischer 344 rats with N-methyl-N-nitrosourea (MNU). After treatment with MNU, the animals were distributed into four experimental groups: Control (without MNU) group, MNU (cancer) group, MNU + PRP group, MNU + BCG group and MNU + PRP + BCG group. Our results demonstrated that PRP treatment alone or associated with BCG triggered significant cytotoxicity in bladder carcinoma cells (HTB-9). Animals treated with PRP associated to BCG clearly showed better histopathological recovery from the cancer state and decrease of urothelial neoplastic lesions progression in 70% of animals when compared to groups that received the same therapies administered singly. In addition, this therapeutic association led to distinct activation of immune system TLRs 2 and 4-mediated, resulting in increased MyD88, TRIF, IRF3, IFN-γ immunoreactivities. Taken together, the data obtained suggest that interferon signaling pathway activation by PRP treatment in combination with BCG immunotherapy may provide novel therapeutic approaches for non-muscle invasive bladder cancer.

Natural Type II Collagen Hydrogel, Fibrin Sealant, and Adipose-Derived Stem Cells as a Promising Combination for Articular Cartilage Repair.

Objective Articular cartilage is an avascular tissue with limited ability of self-regeneration and the current clinical treatments have restricted capacity to restore damages induced by trauma or diseases. Therefore, new techniques are being tested for cartilage repair, using scaffolds and/or stem cells. Although type II collagen hydrogel, fibrin sealant, and adipose-derived stem cells (ASCs) represent suitable alternatives for cartilage formation, their combination has not yet been investigated in vivo for focal articular cartilage defects. We performed a simple experimental procedure using the combination of these 3 compounds on cartilage lesions of rabbit knees. Design The hydrogel was developed in house and was first tested in vitro for chondrogenic differentiation. Next, implants were performed in chondral defects with or without ASCs and the degree of regeneration was macroscopically and microscopically evaluated. Results Production of proteoglycans and the increased expression of collagen type II (COL2α1), aggrecan (ACAN), and sex-determining region Y-box 9 (SOX9) confirmed the chondrogenic character of ASCs in the hydrogel in vitro. Importantly, the addition of ASC induced a higher overall repair of the chondral lesions and a better cellular organization and collagen fiber alignment compared with the same treatment without ASCs. This regenerating tissue also presented the expression of cartilage glycosaminoglycan and type II collagen. Conclusions Our results indicate that the combination of the 3 compounds is effective for articular cartilage repair and may be of future clinical interest.

Contributions for classification of platelet rich plasma - proposal of a new classification: MARSPILL.

Platelet-rich plasma (PRP) has emerged as a significant therapy used in medical conditions with heterogeneous results. There are some important classifications to try to standardize the PRP procedure. The aim of this report is to describe PRP contents studying celular and molecular components, and also propose a new classification for PRP. The main focus is on mononuclear cells, which comprise progenitor cells and monocytes. In addition, there are important variables related to PRP application incorporated in this study, which are the harvest method, activation, red blood cells, number of spins, image guidance, leukocytes number and light activation. The other focus is the discussion about progenitor cells presence on peripherial blood which are interesting due to neovasculogenesis and proliferation. The function of monocytes (in tissue-macrophages) are discussed here and also its plasticity, a potential property for regenerative medicine treatments.

In vitro performance of injectable chitosan-tripolyphosphate scaffolds combined with platelet-rich plasma.

This study aimed to evaluate the in vitro biological effectiveness of chitosan microparticles crosslinked with sodium tripolyphosphate (TPP) in combination with activated pure platelet-rich plasma (aP-PRP) as an injectable composite scaffold for growth factors release, cell proliferation and osteogenic differentiation. Two main novelties were addressed in the field of scaffolds in regenerative medicine: the first is the approach including simultaneously the three vertices of the proliferation triangle formed by the capabilities genic progenitor cells, conductive scaffolds and inductive growth factors, which are provided by platelet rich plasma (PRP); secondly, the approach of an injectable composite scaffolds formed by the fibrin network from aP-PRP and the chitosan microparticles crosslinked with TPP. The microparticles were prepared by vortexing the chitosan and TPP solutions. The ionic crosslinking of chitosan with TPP was made at mass ratios of 2:1, 5:1, and 10:1 at pH 4.0. P-PRP was obtained via the controlled centrifugation of whole blood. The composite scaffolds were prepared by adding the microparticles to immediately activated P-PRP. The results showed that the microparticles had adequate physicochemical and mechanical properties for injection. Furthermore, the microparticles controlled the release of growth factors from P-PRP. The proliferation of human adipose-derived mesenchymal stem cells was lower than in aP-PRP alone but significant at a 2:1 chitosan-TPP mass ratio. Osteogenic differentiation was stimulated at all studied mass ratios, as indicated by the alkaline phosphatase activity. These results offer perspectives for optimizing the composite scaffold, and to prove its potential as an injectable scaffold in regenerative medicine.