Background Chronic leg ulcerations are associated with Haemoglobin disorders, Type2 Diabetes Mellitus, and long-term venous insufficiency, where poor perfusion and altered metabolism develop into a chronic inflammation that impairs wound closure. Skin equivalent organotypic cultures can be engineered in vitro to study skin biology and wound closure by modelling the specific cellular components of the skin. This study aimed to develop a novel bioactive platelet-rich plasma (PRP) leukocyte depleted scaffold to facilitate the study of common clinical skin wounds in patients with poor chronic skin perfusion and low leukocyte infiltration. A scratch assay was performed on the skin model to mimic two skin wound conditions, an untreated condition and a condition treated with recombinant tumour necrotic factor (rTNF) to imitate the stimulation of an inflammatory state. Gene expression of IL8 and TGFA was analysed in both conditions. Statistical analysis was done through ANOVA and paired student t-test. P < 0.05 was considered significant. Results A skin model that consisted of a leukocyte-depleted, platelet-rich plasma scaffold was setup with embedded fibroblasts as dermal equivalents and seeded keratinocytes as multi-layered epidermis. Gene expression levels of IL8 and TGFA were significantly different between the control and scratched conditions (p < 0.001 and p < 0.01 respectively), as well as between the control and treated conditions (p < 0.01 and p < 0.001 respectively). The scratch assay induced IL8 upregulation after 3 h (p < 0.05) which continued to increase up to day 1 (p < 0.05). On the other hand, the administration of TNF led to the downregulation of IL8 (p < 0.01), followed by an upregulation on day 2. IL8 gene expression decreased in the scratched condition after day 1 as the natural healing process took place and was lower than in the treated condition on day 8 (p < 0.05). Both untreated and treated conditions showed a downregulation of TGFA 3 h after scratch when compared with the control condition (p < 0.01). Administration of rTNF showed significant downregulation of TGFA after 24 h when compared with the control (p < 0.01) and treated conditions (p < 0.05). Conclusion This study suggests that a leukocyte-depleted PRP-based skin equivalent can be a useful model for the in vitro study of chronic skin wounds related to poor skin perfusion.
Circulating bone marrow mesenchymal progenitors (BMMPs) are known to be potent antigen-presenting cells that migrate to damaged tissue to secrete cytokines and growth factors. An altered or dysregulated inflammatory cascade leads to a poor healing outcome. A skin model developed in our previous study was used to observe the immuno-modulatory properties of circulating BMMP cells in inflammatory chronic wounds in a scenario of low skin perfusion. BMMPs were analysed exclusively and in conjunction with recombinant tumour necrosis factor alpha (TNFα) and recombinant hepatocyte growth factor (HGF) supplementation. We analysed the expression levels of interleukin-8 (IL-8) and ecto-5′-nucleotidase (CD73), together with protein levels for IL-8, stem cell factor (SCF), and fibroblast growth factor 1 (FGF-1). The successfully isolated BMMPs were positive for both hemopoietic and mesenchymal markers and showed the ability to differentiate into adipocytes, chondrocytes, and osteocytes. Significant differences were found in IL-8 and CD73 expressions and IL-8 and SCF concentrations, for all conditions studied over the three time points taken into consideration. Our data suggests that BMMPs may modulate the inflammatory response by regulating IL-8 and CD73 and influencing IL-8 and SCF protein secretions. In conclusion, we suggest that BMMPs play a role in wound repair and that their induced application might be suitable for scenarios with a low skin perfusion.
Colorectal cancer (CRC) is the third most common cancer worldwide. It has also been demonstrated that over the last ten years the incidence of CRC among younger people below the age of 50 is also increasing. Screening for colorectal cancer is of utmost importance; the rationale behind screening is to target the malignancy and reduce the incidence and mortality of the disease. Diagnostic methods to screen for incidence or relapse are therefore a requisite to detect cancer as early as possible. Scientific findings demonstrate that many deaths are due to lack of screening and therefore early identification will lead to greater survivability. In colorectal cancer, diagnostic tests include liquid biopsy biomarkers. Since the discovery of microRNAs (miRNAs), many studies have demonstrated the relationship between miRNAs and the various sub-types of CRC. Several miRNAs have been identified after analysing serum or plasma samples in patients, and such miRNAs were found to be significantly dysregulated. Such findings place the possibility of miRNAs to be at the epicentre of novel diagnostic techniques for CRC identification and sub-type stratification, including other characteristics associated with CRC development such as patient prognosis. The following review serves to underline the latest findings for miRNAs with such potential for routine diagnostic employment in CRC diagnostics and treatments.
We intended to reformulate an existing platelet-derived wound healing formula to target each phase of the healing wound with the appropriate phase-specific molecules. A decreased perfusion of the skin, often associated with conditions such as thalassemia, sickle cell disease, diabetes mellitus, and chronic vascular disease, is the most common etiology of cutaneous ulcers and chronic wounds. We had previously shown that a PDWHF topically applied to a chronic nonhealing ulcer of a β-thalassemia homozygote stimulated and accelerated closure of the wound. The PDWHF was prepared from a pooled platelet concentrate of a matching blood group, consisting of a combination of platelet α-granule-derived factors. Processing of the apheresis-pooled platelets yielded various amounts of proteins ( 3.36 g / mL ± 0.25 (SD) ( N = 10 )) by the better lysis buffer method. Immunoglobulin G was found to be the most abundant α-granule-secreted protein. Equally broad quantities of the IgG ( 10.76 ± 12.66 % (SD) ( N = 10 )) and IgG/albumin ratios ( 0.6 ± 0.4 (SD) ( N = 10 )) were quantified. We have developed a method using a reformulated lysis buffer followed by size exclusion chromatography and affinity chromatography to extract, identify, quantify, and purify IgG from activated platelets. IgG purification was confirmed by Western blot and flow cytometry. It was thought unlikely that the platelet IgG could be accounted for by adsorption of plasma protein, though the variable quantities could account for diversity in wound healing rates. The IgG could protect the wound even from subclinical infections and functionally advance healing. It may be useful in the management of skin ulcers in the early phase of wound healing.
Background: Chronic leg ulcerations are associated with Haemoglobin disorders, Type 2 Diabetes Mellitus, and long-term venous insufficiency. Mesenchymal stem cells (MSCs) ability to modulate the inflammatory response represents the fundamental requisite for their applicability as a treatment of chronic wounds.Methods: This study aimed to develop a novel bioactive platelet-rich plasma (PRP)-leukocytes-depleted scaffold to reproduce typical clinical wound of patients with poor chronic skin perfusion and low leucocytes infiltration. After scratching the wound model to mimic injury three conditions were compared; an untreated condition, a condition treated with recombinant TNF to mimic an inflammatory state and a condition treated with TNF and also with MSCs to evaluate how the latter’s immunomodulatory properties affect the therapeutic outcomes in an inflammatory state. Gene expression of IL8 and TGFA were analysed in biological triplicates of the three conditions. Statistical analysis was done through a paired student t-test and a p <0.05 was considered significant.Results: We set up a skin model that consisted of a leukocyte-depleted, platelet-rich plasma scaffold, with embedded fibroblasts as dermal equivalent and seeded keratinocytes on it as multi-layered epidermidis. IL8 expression increased upon scratching (p=0.014) and continued to increase up to day 1 (p=0.048). IL8 expression decreased upon administration of TNF (p=0.005) but then increased again. IL8 expression decreased in the untreated condition after day 1 as the natural healing process took place and was lower than in treated conditions in day 8 (p=0.048). TGFA expression decreased upon scratching (p=0.006) and increased again in day 1, more so in the untreated than in the treated conditions (p=0.02). TGFA expression decreased again in day 4 in the study group before increasing sharply (p=0.027) in day 8 to reach pre-scratch levels. Conclusion: This study found that a leukocyte-depleted PRP-based skin equivalent can be useful in the study of treatments of chronic wounds. This study also indicates that MSCs appear to modulate the expression of IL8 by switching from an immunosuppressive phenotype to a pro-inflammatory phenotype. These results indicate that the administration of MSCs could offer a potential therapeutic approach for the treatment of leg ulcers in patients with poor skin perfusion.
Flow cytometric determination of peripheral blood CD34+ cells provides reliable measurements of circulating hemopoietic progenitors. Since the detection of the absolute number of circulating CD34+ cells has been found of clinical utility in the setting of chronic myeloproliferative disorders, we investigated whether peripheral CD34+ cells could play any role in the clinical work-up of B-cell chronic lymphocytic leukemia (B-CLL). In this view, we determined by flow cytometry the absolute number of circulating CD34+ cells in the peripheral blood of 28 patients (16 males and 12 females, median age 67 years) affected by typical B-CLL (Matutes score 5,4,3) and in different Rai stages of the disease (19 early stage: Rai 0, I, II; 9 advanced stage: Rai III, IV). Conventional and multiparameter flow cytometric analysis was performed utilizing a FACSCalibur cytometer (Becton Dickinson). Our data showed a significant increase in the number of circulating CD34+ cells in the peripheral blood of patients with B-CLL (median CD34+ cells:7.8mL) as compared to controls (median CD34+ cells 0.1mL) (p=0.008). No statistical difference between B-CLL patients in early versus advanced stage (p=0.5) and between untreated versus treated (p=0.7) was found, as well as there was no correlation with some of the clinical characteristics of B-CLL (WBC-count, LDH levels, Beta-2M). In 10 out of 28 B-CLL affected patients, circulating CD34+ cells were correlated with ZAP-70 and CD38 antigen but no correlation was found. In addition, we detected in the peripheral blood of 22 out of 28 patients small numbers of circulating CD34+ cells displaying the CD19+/CD5+ phenotype (median CD34+/CD19+/CD5+ cells:5.7mL) whereas these cells were absent in normal controls. This unexpected finding, whose significance remains to be clarified and still restricted to a small number of cases, could be directly correlated to the underlying lymphproliferative disease and might represent a pool of leukemic stem cells. However, further studies are warranted.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.