Lyophilised Platelet-Rich Fibrin: Physical and Biological Characterisation.

BACKGROUND: Platelet-rich fibrin (PRF) has gained popularity in craniofacial surgery, as it provides an excellent reservoir of autologous growth factors (GFs) that are essential for bone regeneration. However, the low elastic modulus, short-term clinical application, poor storage potential and limitations in emergency therapy use restrict its more widespread clinical application. This study fabricates lyophilised PRF (Ly-PRF), evaluates its physical and biological properties, and explores its application for craniofacial tissue engineering purposes. MATERIAL AND METHODS: A lyophilisation method was applied, and the outcome was evaluated and compared with traditionally prepared PRF. We investigated how lyophilisation affected PRF's physical characteristics and biological properties by determining: (1) the physical and morphological architecture of Ly-PRF using SEM, and (2) the kinetic release of PDGF-AB using ELISA. RESULTS: Ly-PRF exhibited a dense and homogeneous interconnected 3D fibrin network. Moreover, clusters of morphologically consistent cells of platelets and leukocytes were apparent within Ly-PRF, along with evidence of PDGF-AB release in accordance with previously reports. CONCLUSIONS: The protocol established in this study for Ly-PRF preparation demonstrated versatility, and provides a biomaterial with growth factor release for potential use as a craniofacial bioscaffold.

Estimulación facial con factores de crecimiento plaquetario en consulta de Dermatología / Facial stimulation with platelet growth factors in Dermatology consultation

RESUMEN El envejecimiento es un proceso complejo que trae consigo cambios celulares, histológicos y cutáneos. Estos últimos son una de sus manifestaciones más evidentes. El plasma rico en plaquetas es una fuente fiable de obtención de células para regenerar tejidos; por su fácil disponibilidad es un material inocuo. La bioestimulación con el mismo, por su parte, es un conjunto de procedimientos para activar las funciones anabólicas de los fibroblastos, producción de colágeno, elastina y ácido hialurónico. La tendencia al empleo de este en tratamientos antiedad es cada vez mayor. El objetivo de este trabajo fue realizar una actualización del tema, para exponer aspectos importantes sobre formas de aplicación, indicaciones, complicaciones y contraindicaciones. Existen varios métodos para la bioestimulación facial, tales como la realización de pápulas, napagge y retroinyección. Se han empleado en alopecia androgénica, areata, envejecimiento cutáneo, etc. Las complicaciones más observadas son dolor, eritema, ardor y sangrado local. Entre las contraindicaciones más comunes se observan el herpes simple recidivante, coagulopatías, tratamiento con anticoagulantes, colagenopatías y neoplasias (AU).

ABSTRACT Aging is a complex process that brings with it cellular, histological and cutaneous changes, the latter being one of its most obvious manifestations. Platelet-rich plasma is a reliable source of cells to regenerate tissues; due to its easy availability, it is a harmless material. Bio-stimulation with it is a set of procedures to activate the fibroblasts anabolic functions and the production of collagen, elastin and hyaluronic acid. The tendency to use it in anti-aging treatments increases faster and faster. The objective of this work was updating the topic to expose important aspects about application methods, indications, complications and contraindications. There are several methods of applying facial bio-stimulation such as performing papules, napagge, and retroinjection. It has been used in androgenic alopecia, alopecia areata, cutaneous ageing, etc. The most commonly found complications are pain, erythema, burning and local bleeding. The most common contraindications include recidivist herpes simplex, coagulopaties, anticoagulant treatment, collagen-related diseases and neoplasms (AU).

Contralesional Application of Transcranial Direct Current Stimulation on Functional Improvement in Ischemic Stroke Mice.

BACKGROUND AND PURPOSE: The therapeutic use of transcranial direct current stimulation (tDCS), an adjuvant tool for stroke, induces long-term changes in cortical excitability, for example, the secretion of activity-dependent growth factors. We assessed the proper therapeutic configuration of high-definition tDCS (HD-tDCS) in the subacute stage of ischemic stroke and its underlying expression profiling of growth factors to propose a new method for ensuring better therapeutic effects. METHODS: Male C57BL/6J mice were subjected to middle cerebral artery occlusion, after which repetitive HD-tDCS (20 minutes, 55 µA/mm2, charge density 66 000 C/m2) was applied from subacute phases of their ischemic insult. Behavioral tests assessing motor and cognitive functions were used to determine suitable conditions and HD-tDCS stimulation sites. Gene expression profiling of growth factors and their secretion and activation were analyzed to shed light on the underlying mechanisms. RESULTS: Anodal HD-tDCS application over the contralesional cortex, especially the motor cortex, was more effective than ipsilesional stimulation in attenuating motor and cognitive deficits. In the HD-tDCS application over the contralesional motor cortex, positive changes in Bmp8b, Gdf5, Il4, Pdgfa, Pgf, and Vegfb were observed in the ipsilesional site. The expression of GDF5 (growth/differentiation factor 5) and PDGFA (platelet-derived growth factor subunit A) tended to similarly increase in both ipsi- and contralesional striata. However, higher expression levels of GDF5 and PDGFA and their receptors were observed in the peri-infarct regions of the striatum after HD-tDCS, especially in PDGFA expression. A higher number of proliferating or newly formed neuronal cells was detected in ipsilesional sites such as the subventricular zone. CONCLUSIONS: Application of anodal HD-tDCS over the contralesional cortex may enhance beneficial recovery through the expression of growth factors, such as GDF5 and PDGFA, in the ipsilesional site. Therefore, this therapeutic configuration may be applied in the subacute stage of ischemic stroke to ameliorate neurological impairments.

CCL3, IL-7, IL-13 and IFNγ transcripts are increased in skin's biopsy of systemic sclerosis.

Although several cytokines and chemokines have been investigated as possible mediators of fibrosis in systemic sclerosis (SSc), specific correlation between cytokines and organ involvement have not been found yet, and a cytokine profile characteristic of SSc is far to be identified. We studied the profile of antifibrotic and profibrotic transcripts involved in skin of SSc patients. The mRNA expression was detected by fluorescence-based quantitative real-time PCR (qPCR) in skin's biopsies from 14 patients with SSc and 5 healthy controls. PDGF-A, CTGF, CCL3, IL-6, IL-13, IL-7, IFNγ, IL-17, IL-22 and RORc were analysed in these samples. CCL3, IL-7, IL-13 and IFN-γ were more expressed in skin's biopsy of patients with SSc (P = 0.0002, P = 0.0082, P = 0.0243, P = 0.0335, respectively) when compared with healthy controls. We also found a positive correlation between CCL3 and IL-7 transcripts (P = 0.0050 r = 0.7187). Furthermore, we observed that patients with lung involvement had lower expression of PDGF-A (P = 0.0385). We found an increase in IL-7, IFN-γ, CCL3 and IL-13 relative mRNA expressions on the skin's biopsy of patients with SSc, and a positive correlation between IL-7 and CCL3. These molecules are involved in the pathogenesis of SSc, and how their interactions occur should be the subject of further studies.

Meningitic Escherichia coli-induced upregulation of PDGF-B and ICAM-1 aggravates blood-brain barrier disruption and neuroinflammatory response.

BACKGROUND: Blood-brain barrier (BBB) disruption and neuroinflammation are considered key mechanisms of pathogenic Escherichia coli invasion of the brain. However, the specific molecules involved in meningitic E. coli-induced BBB breakdown and neuroinflammatory response remain unclear. Our previous RNA-sequencing data from human brain microvascular endothelial cells (hBMECs) revealed two important host factors: platelet-derived growth factor-B (PDGF-B) and intercellular adhesion molecule-1 (ICAM-1), which were significantly upregulated in hBMECs after meningitic E. coli infection. Whether and how PDGF-B and ICAM-1 contribute to the development of E. coli meningitis are still unclear. METHODS: The western blot, real-time PCR, enzyme-linked immunosorbent assay, immunohistochemistry, and immunofluorescence were applied to verify the significant induction of PDGF-B and ICAM-1 by meningitic E. coli in vivo and in vitro. Evan's blue assay and electric cell-substrate impedance sensing assay were combined to identify the effects of PDGF-B on BBB permeability. The CRISPR/Cas9 technology, cell-cell adhesion assay, and electrochemiluminescence assay were used to investigate the role of ICAM-1 in neuroinflammation subversion. RESULTS: We verified the significant induction of PDGF-B and ICAM-1 by meningitic E. coli in mouse as well as monolayer hBMECs models. Functionally, we showed that the increase of PDGF-B may directly enhance the BBB permeability by decreasing the expression of tight junction proteins, and the upregulation of ICAM-1 contributed to neutrophils or monocytes recruitment as well as neuroinflammation subversion in response to meningitic E. coli infection. CONCLUSIONS: Our findings demonstrated the roles of PDGF-B and ICAM-1 in mediating bacterial-induced BBB damage as well as neuroinflammation, providing new concepts and potential targets for future prevention and treatment of bacterial meningitis.

Molecular and Cellular Effect of Angiotensin 1-7 on Hypertensive Kidney Disease.

BACKGROUND: Studies implicate that angiotensin 1-7 (Ang1-7) imparts protective effects in the kidney. However, its relevance in hypertensive kidney disease is not fully understood. The purpose of this study was to explore the role of Ang1-7 on renal damage/remodeling during hypertension and its potential underlying molecular-cellular mechanisms. METHODS: Hypertension was induced in adult Sprague-Dawley rats by infusion of aldosterone (ALDO; 0.75 µg/hour) for 4 weeks with or without co-treatment of Ang1-7 (1 mg/kg/day). Untreated rats served as controls. Systolic blood pressure was monitored by tail-cuff technique. Renal fibrosis was evaluated by picrosirius red staining and renal collagen volume fraction was quantitated using imaging analyzing system. The expression of profibrotic factors [transforming growth factor-ß1 (TGF-ß1), platelet-derived growth factor-D (PDGF-D), fibroblast growth factor-1 (FGF-1), vascular endothelial growth factor-D (VEGF-D), and tissue inhibitors of metalloproteinases (TIMPs)] and free radical producing enzymes (inducible nitric oxide synthase and nicotinamide adenine dinucleotide phosphate [NADPH] oxidase) in the kidney were examined by reverse transcription-polymerase chain reaction and western blot. Renal oxidative stress was assessed by malondialdehyde (MDA) measurement. RESULTS: Chronic ALDO infusion caused hypertension and hypertensive renal disease represented as glomerular damage/sclerosis. Ang1-7 co-treatment did not affect blood pressure in ALDO-treated rats, but significantly attenuated the glomerular damage/fibrosis. ALDO treatment significantly elevated renal expression of profibrogenic factors, including TGF-ß1, TIMP-1/TIMP-2, FGF-1, PDGF-D, and VEGF-D, whereas Ang1-7 co-treatment significantly reduced renal TGF-ß1, TIMP-1/TIMP-2, and FGF-1, but not PDGF-D and VEGF-D. Furthermore, ALDO infusion elevated NADPH oxidase (gp91phox) and MDA in the kidney, which was attenuated by Ang1-7 co-treatment. CONCLUSIONS: Ang1-7 plays a protective role in the hypertensive kidney disease independent of blood pressure. The beneficial effects of Ang1-7 are likely mediated via suppressing TGF-ß/FGF-1 pathways and oxidative stress.

Overexpression of matriptase in tumor stroma is a poor prognostic indicator of extrahepatic bile duct cancer.

Bile duct cancer is known to contain numerous fibroblasts, and reported to recruit cancer- associated fibroblasts by secreting platelet-derived growth factor-D (PDGF-D) which needs serine proteases, such as matriptase, to behave as a ligand. However, their expression pattern, and prognostic value have not been clarified. In this study, we investigated the clinicopathological significance of PDGF-D and matriptase expression in patients with extrahepatic bile duct cancer. The samples were obtained from 256 patients who underwent the surgical resection between 1991 and 2015, and the expression levels of PDGF-D and matriptase were evaluated immunohistochemically. Staining intensities and distribution were scored, and finally classified into low and high expression groups in cancer cells and stroma respectively. High expression of matriptase in the cancer stroma was detected in 91 tumors (40%). The high stromal matriptase expression was significantly associated with shorter recurrence-free survival (RFS) and overall survival (OS) (P = 0.0027 and 0.0023, respectively). Multivariate analyses also demonstrated that the stromal matriptase expression level was an independent influential factor in RFS (P = 0.0050) and OS (P = 0.0093). Our findings suggest that the high stromal matriptase expression was strongly associated with tumor progression, recurrence and poor outcomes in patients with extrahepatic bile duct cancer.

Alcohol Consumption in Combination with an Atherogenic Diet Increased Indices of Atherosclerosis in Apolipoprotein E/Low-Density Lipoprotein Receptor Double-Knockout Mice.

BACKGROUND: Alcohol abuse and adherence to atherogenic diet (AD; a low-carbohydrate-high-protein diet) have been positively associated with cardiovascular disease. In addition, it has been demonstrated clinically that dietary intake is increased on days when alcohol is consumed. Here, the additive effects of ethanol (EtOH) and AD on atherosclerosis, a major underlying cause of cardiovascular disease, were investigated in apolipoprotein E/low-density lipoprotein receptor double-knockout (KO) mice. The mechanisms, especially aortic oxidative stress damage, were highlighted. METHODS: Twelve-week-old male KO mice on AD with or without EtOH treatment were bred for 4 months. Age-matched male C57BL/6J mice on a standard chow diet without EtOH treatment served as controls. Analyses were conducted using ultrasound biomicroscopy, histopathological and fluorescence immunohistochemical examinations, Western blots, and polymerase chain reaction. RESULTS: KO mice on AD with EtOH treatment showed increases in aortic maximum intima media thickness, hypoechoic plaque formation, and mean Oil-Red-O content. These results were associated with enhanced ratio of aortic 8-hydroxy-2'-deoxyguanosine (8-OHdG)-immunopositive area to the metallothionein (MT) immunopositive area and suppression of AD-induced up-regulated aortic Mt1, Mt2, and upstream stimulatory factor 1 mRNA expressions. Moreover, 8-OHdG was expressed in the nuclei of CD31- and alpha smooth muscle actin-immunopositive cells, and the up-regulated mRNA expressions of aortic nitric oxide synthase 3 and platelet-derived growth factors were only observed in the KO mice on AD with EtOH treatment. CONCLUSIONS: Alcohol abuse and adherence to AD may promote the shift of aortic oxidative stress and antioxidative stress balance toward oxidative stress predominance and reduced antioxidative stress, which may be partly due to the decrease in MT at the cell biological level and down-regulation of Mt at the gene level, which in turn could play a role in the up-regulation of endothelial dysfunction-related and vascular smooth muscle cell proliferation-related gene expression and the progression of atherosclerosis in mice with hyperlipidemia.

Characterization of induced pluripotent stem cell-derived megakaryocyte lysates for potential regenerative applications.

Recently, platelet-derived growth factors present in lysates became an extreme interest in the field of regenerative medicine such as in wound healing and as substitutes to foetal bovine serum in xeno-free cell culture systems. However, the generation of such platelet lysates completely depends on the availability of platelet donors. In this study, the possibility to use in vitro-generated megakaryocytes derived from induced pluripotent stem cells (iPSCs) as a cell source for typical platelet growth factors was investigated. Therefore, the presence and levels of those factors were characterized in in vitro-produced megakaryocytes. In comparison with platelets, in vitro-generated megakaryocytes showed a multifold increased content in transcript and protein levels of typical platelet growth factors including platelet-derived growth factors (PDGFs), transforming growth factor (TGF)-1ß, vascular endothelial cell factor (VEGF)-A, epidermal growth factor (EGF), insulin-like growth factor (IGF)-1 and tissue factor (TF). Hence, iPSC-derived megakaryocytes may serve as an efficient cell source for a donor-independent generation of growth factor-rich lysates with a broad application potential in innovative cell culture systems and regenerative therapies.

Effects of vitrification and transplantation on follicular development and expression of EphrinB1 and PDGFA in mouse ovaries.

The aim of this study was to assess the follicular development and the patterns of EphrinB1 and PDGFA immunostaining in vitrified mouse ovarian tissue (OT) with and without transplantation. Histological evaluation was performed on fresh and vitrified OTs, whether transplanted or not. RT-PCR was performed on fresh and vitrified ovarian samples (OSs) and vitrified OS graft. Vitrification alone did not significantly reduce the normal primordial, primary, and secondary follicles except antral ones (p > 0.05). However, transplantation decreased all the follicle types. The EphrinB1 immunoexpression showed high intensity in all follicular types in vitrified OT and the significant increased was detected in secondary and antral follicles (p < 0.05). PDGFA protein immunoexpression of primordial and primary follicles was decreased in vitrified OT (p < 0.05). However, the lowest immunoexpression of EphrinB1 and PDGFA was detected after transplantation (p < 0.05). The levels of ephrinb1 and pdgfa mRNA expressions in vitrified OS and vitrified OS grafts were found as comparable to the fresh OS. In conclusion, vitrification has no detrimental effect on the follicles at the different developmental stages, majority of ovarian follicular loss takes place after transplantation rather than vitrification. Overall, vitrification and grafting do not change the ephrinb1 and pdgfa gene expressions. In addition, EphrinB1 and PDGFA are expressed during different stages of folliculogenesis in a different manner in fresh, vitrified, or grafted OTs. Vitrification and/or grafting appear to affect the follicular expression of EphrinB1 and PDGFA. These findings suggest that these proteins could have several functions related to the development of follicles and angiogenesis after transplantation.

PDGF Family Expression in Glioblastoma Multiforme: Data Compilation from Ivy Glioblastoma Atlas Project Database.

Glioblastoma Multiforme (GBM) is the most frequent and lethal primary brain cancer. Due to its therapeutic resistance and aggressiveness, its clinical management is challenging. Platelet-derived Growth Factor (PDGF) genes have been enrolled as drivers of this tumour progression as well as potential therapeutic targets. As detailed understanding of the expression pattern of PDGF system in the context of GBM intra- and intertumoral heterogeneity is lacking in the literature, this study aims at characterising PDGF expression in different histologically-defined GBM regions as well as investigating correlation of these genes expression with parameters related to poor prognosis. Z-score normalised expression values of PDGF subunits from multiple slices of 36 GBMs, alongside with clinical and genomic data on those GBMs patients, were compiled from Ivy Glioblastoma Atlas Project - Allen Institute for Brain Science data sets. PDGF subunits show differential expression over distinct regions of GBM and PDGF family is heterogeneously expressed among different brain lobes affected by GBM. Further, PDGF family expression correlates with bad prognosis factors: age at GBM diagnosis, Phosphatase and Tensin Homolog deletion and Isocitrate Dehydrogenase 1 mutation. These findings may aid on clinical management of GBM and development of targeted curative therapies against this devastating tumour.

PDGF-CC underlies resistance to VEGF-A inhibition and combinatorial targeting of both suppresses pathological angiogenesis more efficiently.

Anti-VEGF-A therapy has proven to be effective for many neovascular diseases. However, drug resistance to anti-VEGF-A treatment can develop. Also, not all patients with neovascular diseases are responsive to anti-VEGF-A treatment. The mechanisms underlying these important issues remain unclear. In this study, using different model systems, we found that inhibition of VEGF-A directly upregulated PDGF-CC and its receptors in multiple cell types in pathological angiogenesis in vitro and in vivo. Importantly, we further revealed that combinatorial targeting of VEGF-A and PDGF-CC suppressed pathological angiogenesis more efficiently than monotherapy. Given the potent angiogenic activity of PDGF-CC, our findings suggest that the development of resistance to anti-VEGF-A treatment may be caused by the compensatory upregulation of PDGF-CC, and combined inhibition of VEGF-A and PDGF-CC may have therapeutic advantages in treating neovascular diseases.

Tadalafil Promotes the Recovery of Peripheral Neuropathy in Type II Diabetic Mice.

We previously demonstrated that treatment of diabetic peripheral neuropathy with the short (4 hours) half-life phosphodiesterase 5 (PDE5) inhibitor, sildenafil, improved functional outcome in diabetic db/db mice. To further examine the effect of PDE5 inhibition on diabetic peripheral neuropathy, we investigated the effect of another potent PDE5 inhibitor, tadalafil, on diabetic peripheral neuropathy. Tadalafil is pharmacokinetically distinct from sildenafil and has a longer half-life (17+hours) than sildenafil. Diabetic mice (BKS.Cg-m+/+Leprdb/J, db/db) at age 20 weeks were treated with tadalafil every 48 hours for 8 consecutive weeks. Compared with diabetic mice treated with saline, tadalafil treatment significantly improved motor and sensory conduction velocities in the sciatic nerve and peripheral thermal sensitivity. Tadalafil treatment also markedly increased local blood flow and the density of FITC-dextran perfused vessels in the sciatic nerve concomitantly with increased intraepidermal nerve fiber density. Moreover, tadalafil reversed the diabetes-induced reductions of axon diameter and myelin thickness and reversed the diabetes-induced increased g-ratio in the sciatic nerve. Furthermore, tadalafil enhanced diabetes-reduced nerve growth factor (NGF) and platelet-derived growth factor-C (PDGF-C) protein levels in diabetic sciatic nerve tissue. The present study demonstrates that tadalafil increases regional blood flow in the sciatic nerve tissue, which may contribute to the improvement of peripheral nerve function and the amelioration of diabetic peripheral neuropathy.

A Positive Feed-forward Loop Associating EGR1 and PDGFA Promotes Proliferation and Self-renewal in Glioblastoma Stem Cells.

Glioblastomas are the most common primary brain tumors, highly vascularized, infiltrating, and resistant to current therapies. This cancer leads to a fatal outcome in less than 18 months. The aggressive behavior of glioblastomas, including resistance to current treatments and tumor recurrence, has been attributed to glioma stemlike/progenitor cells. The transcription factor EGR1 (early growth response 1), a member of a zinc finger transcription factor family, has been described as tumor suppressor in gliomas when ectopically overexpressed. Although EGR1 expression in human glioblastomas has been associated with patient survival, its precise location in tumor territories as well as its contribution to glioblastoma progression remain elusive. In the present study, we show that EGR1-expressing cells are more frequent in high grade gliomas where the nuclear expression of EGR1 is restricted to proliferating/progenitor cells. We show in primary cultures of glioma stemlike cells that EGR1 contributes to stemness marker expression and proliferation by orchestrating a PDGFA-dependent growth-stimulatory loop. In addition, we demonstrate that EGR1 acts as a positive regulator of several important genes, including SHH, GLI1, GLI2, and PDGFA, previously linked to the maintenance and proliferation of glioma stemlike cells.

FoxM1 Drives a Feed-Forward STAT3-Activation Signaling Loop That Promotes the Self-Renewal and Tumorigenicity of Glioblastoma Stem-like Cells.

The growth factor PDGF controls the development of glioblastoma (GBM), but its contribution to the function of GBM stem-like cells (GSC) has been little studied. Here, we report that the transcription factor FoxM1 promotes PDGFA-STAT3 signaling to drive GSC self-renewal and tumorigenicity. In GBM, we found a positive correlation between expression of FoxM1 and PDGF-A. In GSC and mouse neural stem cells, FoxM1 bound to the PDGF-A promoter to upregulate PDGF-A expression, acting to maintain the stem-like qualities of GSC in part through this mechanism. Analysis of the human cancer genomic database The Cancer Genome Atlas revealed that GBM expresses higher levels of STAT3, a PDGF-A effector signaling molecule, as compared with normal brain. FoxM1 regulated STAT3 transcription through interactions with the ß-catenin/TCF4 complex. FoxM1 deficiency inhibited PDGF-A and STAT3 expression in neural stem cells and GSC, abolishing their stem-like and tumorigenic properties. Further mechanistic investigations defined a FoxM1-PDGFA-STAT3 feed-forward pathway that was sufficient to confer stem-like properties to glioma cells. Collectively, our findings showed how FoxM1 activates expression of PDGF-A and STAT3 in a pathway required to maintain the self-renewal and tumorigenicity of glioma stem-like cells.

Functional regulation of adipose-derived stem cells by PDGF-D.

Platelet-derived growth factor-D (PDGF-D) was recently identified, and acts as potent mitogen for mesenchymal cells. PDGF-D also induces cellular transformation and promotes tumor growth. However, the functional role of PDGF-D in adipose-derived stem cells (ASCs) has not been identified. Therefore, we primarily investigated the autocrine and paracrine roles of PDGF-D in this study. Furthermore, we identified the signaling pathways and the molecular mechanisms involved in PDGF-D-induced stimulation of ASCs. It is of interest that PDGF-B is not expressed, but PDGF-D and PDGF receptor-ß are expressed in ASCs. PDGF-D showed the strongest mitogenic effect on ASCs, and PDGF-D regulates the proliferation and migration of ASCs through the PI3K/Akt pathways. PDGF-D also increases the proliferation and migration of ASCs through generation of mitochondrial reactive oxygen species (mtROS) and mitochondrial fission. mtROS generation and fission were mediated by p66Shc phosphorylation, and BCL2-related protein A1 and Serpine peptidase inhibitor, clade E, member 1 mediated the proliferation and migration of ASCs. In addition, PDGF-D upregulated the mRNA expression of diverse growth factors such as vascular endothelial growth factor A, fibroblast growth factor 1 (FGF1), FGF5, leukemia inhibitory factor, inhibin, beta A, interleukin 11, and heparin-binding EGF-like growth factor. Therefore, the preconditioning of PDGF-D enhanced the hair-regenerative potential of ASCs. PDGF-D-induced growth factor expression was attenuated by a pharmacological inhibitor of mitogen-activated protein kinase pathway. In summary, PDGF-D is highly expressed by ASCs, where it acts as a potent mitogenic factor. PDGF-D also upregulates growth factor expression in ASCs. Therefore, PDGF-D can be considered a novel ASC stimulator, and used as a preconditioning agent before ASC transplantation.

[Immunohistochemical changes in the lungs from fetuses and newborn infants at 20- 40 weeks' gestation with false left-sided congenital diaphragmatic hernia].

OBJECTIVE: to study changes in the expression of growth factors in the lungs from fetuses and newborn infants at 20-40 weeks' gestation with false left-sided congenital diaphragmatic hernia (CDH). MATERIAL AND METHODS: Lung fragments obtained at autopsies were examined using immunohistochemically stained paraffin sections. The expression indices of insulin-like growth factor-1 (IGF-1), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and transforming grow factor-ß (TGF-ß) in the fetal lung sections were compared with the results of survey and elective staining techniques, the morphometric data of digitized lung sections, and the indicators obtained in the comparison group. RESULTS: Morphofunctional changes in the connective tissue, pulmonary vessels, and bronchial and alveolar epithelium at 20-24, 25-27, and 28-40 weeks' gestation were characterized, partly explaining the development of bilateral pulmonary hypoplasia in CDH. There was evidence for the involvement of PDGF, IGF-1, and EGF in primary pulmonary hypoplasia. PDGF deficiency plays a certain role in secondary pulmonary hypoplasia. CONCLUSION: The findings can be used in researches and in the practical work of pathologists and forensic medical experts.

Platelet-derived growth factors and receptors in Canine Lymphoma.

Platelet-derived growth factors (PDGFs) belong to a family of polypeptide growth factors that signal through cell surface tyrosine kinase receptors to stimulate growth, proliferation and differentiation. Platelet-derived growth factor receptors (PDGFRs) are also considered important targets for specific kinase inhibitors in the treatment of several human tumours. The aim of this study was to investigate the role of PDGF-A, PDGF-B, PDGFR-α and PDGFR-ß in canine lymphoma by determining gene and protein expression in lymph nodes of dogs with diffuse large B-cell lymphoma (DLBCL), peripheral T-cell lymphoma (PTCL), T-lymphoblastic lymphoma (T-LBL) and in healthy control dogs. One lymph node was also studied at the end of therapy in a subset of dogs in remission for DLBCL. In controls, PDGF-A, PDGFR-α and PDGFR-ß mRNA levels were significantly higher than in DLBCLs, PTCLs and T-LBLs. However, PDGFR-α and PDGFR-ß were minimally expressed by lymphocytes and plasma cells in normal lymph nodes as determined by immunohistochemistry, while neoplastic B and T cells showed the highest score (P <0.05). This discordant result may be compatible with the constitutive expression of these molecules by endothelial cells and fibroblasts in normal lymph nodes, thereby influencing gene expression results. Furthermore, these cells were not included in the immunohistochemical analysis. Similarly, dogs with DLBCL that were in remission at the end of therapy showed significantly higher gene expression of PDGFs and receptors than at the time of diagnosis and with an opposite trend to the protein assay. PDGF-B protein and mRNA were overexpressed in PTCLs and T-LBLs when compared with DLBCLs and controls (P <0.05). Additionally, there was a correlation between protein expression of PDGF-B and both PDGFRs in PTCLs and T-LBLs, suggesting an autocrine or paracrine loop in the aetiology of aggressive canine T-cell lymphomas. These data provide a rationale for the use of PDGFR antagonists in the therapy of aggressive T-cell lymphomas, but not in DLBCLs.

Primary platelet-derived growth factor-producing, spindle-shaped diffuse large B-cell lymphoma of the skull: a case report and literature review.

A 39-year-old woman with a right frontal mass underwent a cranial bone tumor biopsy. Histopathologic examination of hematoxylin and eosin-stained slides showed spindle-shaped tumor cells in a storiform pattern, appearing somewhat like a sarcoma. However, the tumor cells were CD20-positive by immunohistochemical staining. Therefore, a diagnosis of spindle-shaped diffuse large B-cell lymphoma (Sp-DLBCL) was made. There have been at least 35 cases of Sp-DLBCL documented in the literature, and most were of the germinal center type, while the present case is the first report of a vimentin-positive primary Sp-DLBCL of the skull. The DLBCL in this case was immunohistochemically stained for six representative cytokines that might give rise to fibrosis, due to the evidence of fibroblastic proliferation. The DLBCL cells were positive for platelet-derived growth factor (PDGF), and some cells were also positive for tumor necrosis factor (TNF) α. Based on these findings, it was inferred that the PDGF and TNFα produced by DLBCL cells induced fibroblastic proliferation. The resultant conspicuous fibrosis caused interfibrous impingement on the DLBCL cells, which deformed them into a spindle shape. The present case is the first reported case of a PDGF-producing Sp-DLBCL.

Downregulation of angiogenesis factors, VEGF and PDGF, after rapid IgE desensitization and oral immunotherapy in children with food allergy.

BACKGROUND: Angiogenesis has a key role in several conditions and is regulated by several factors such as the platelet-derived growth factor (PDGF) or the vascular endothelial growth factor (VEGF). The goal of this study was to investigate the possible role of PDGF and VEGF in a group of patients with severe food allergy. METHODS: We design a prospective longitudinal study (n = 30) with patients with persistent cow's milk proteins (CMP) allergy. After achieving a CMP rush desensitization protocol, a clinical followup including SPT and blood samples to determine sIgE, protein levels, PDGF, and VEGF-A and a panel of the most representative Th1, Th2, Treg, and Th17 cytokines were also monitored. RESULTS: Baseline levels of PDGF and VEGF in the CMP allergic patients (1170 pg/mL and 253 pg/mL) were different compared to those nonallergic CMP control subjects (501 pg/mL and 108 pg/mL). Both PDGF and VEGF were significantly downregulated (P < 0.05) 6 months after completion of the CMP desensitization process and remained significantly decreased 12 months later. CONCLUSION: The present study shows a significant increase of PDGF and VEGF in anaphylaxis suffering children compared to a control group. Interestingly, both VEGF and PDGF were significantly downregulated after completing a full CMP rush IgE desensitization.