Wound Healing Process In Mice Research Articles

Photodynamic therapy mediated by methylene blue-loaded PEG accelerates skin mouse wound healing: an immune response.

Conventional approaches for enhancing wound healing may not always yield satisfactory results. Instead, we test the effectiveness of a newly developed photodynamic therapy (PDT) that uses methylene blue (MB) loaded with polyethylene glycol (PEG) (MB-PEG) hydrogel to accelerate wound healing process in mice. A dorsal skin incision with 6mm punch which topically subjected to MB-PEG hydrogel and a low-level laser light of red light to assess the regeneration process of wounded skin. A total of 63 adult male CD1 mice divided into normal group (no treatment) and other wound groups received different treatments of laser (650 ± 5nm and power intensity of 180 mW/cm2), MB-PEG, or PDT (MB-PEG followed by laser). The wound healing parameters were investigated by histological examination of the skin and measuring of proinflammatory cytokines at the early stage (48h) and a late one on day 21. at 48h, the score of tissue granulation, inflammation, and angiogenesis process were markedly improved in wounded groups that received MB + PEG combined with laser compared to the group treated with laser alone. On day 21, a significant improvement of the inflammation was detected in the group treated with MB + PEG plus laser compared to the other groups. At 48h, the upregulated serum levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the wound group were significantly (P < 0.001) reduced in the group treated with MB + PEG combined with laser. MB-PEG based hydrogel improves and accelerates wound closure in the context of laser compared to either single treatment.

MOF/MXene-loaded PVA/chitosan hydrogel with antimicrobial effect and wound healing promotion under electrical stimulation and improved mechanical properties

Electrical stimulation modulates cell behavior and influences bacterial activity, so highly conductive, antimicrobial hydrogels are suitable for promoting wound healing. In this study, highly conductive and antimicrobial Ti3C2Tx (MXene) hydrogels composed of chitosan and poly(vinyl alcohol) and AgCu- H2PYDC MOF were developed. In PVACS/MOF/MXene (PCMM) hydrogels, the MXene layer acts as an electrical conductor. The electrical conductivity is 0.61 ± 0.01 S·cm−1. PCMM hydrogels modulate cell behavior and provide ES antimicrobial capacity under ES at 1 V. The metal ions of MOF form coordination with chitosan molecules and increase the cross-linking density between chitosan molecules, thus improving the mechanical properties of the hydrogel (tensile strength 0.088 ± 0.04 MPa, elongation at break 233 ± 11 %). The PCMM gels had good biocompatibility. The PCMM hydrogels achieved 100 % antibacterial activity against E. coli and S. aureus for 12 h. 1 V electrical stimulation of PCMM hydrogel accelerated the wound healing process in mice by promoting cell migration and neovascularization, achieving 97 ± 0.4 % wound healing on day 14. The hydrogel dressing PCMM-0.1 with MOF addition of 0.1 % had the best wound healing promoting effect and which is a promising dressing for promoting wound healing and is a therapeutic strategy worth developing.

Diabetic wound healing potential of silk sericin protein based hydrogels enriched with plant extracts

The complications associated with diabetic wounds make their healing process prolonged. Hydrogels could be ideal wound dressings therefore present research was conducted to prepare silk sericin (an adhesive protein polymer) based hydrogels in combination with plant extracts and to evaluate its effectiveness against wound healing process in mice with alloxan induced diabetes. Excision wounds were formed via a biopsy puncture (6 mm). Experimental hydrogels were prepared and applied topically on the diabetic wounds. All the hydrogel treatment groups showed significantly higher (P < 0.001) percent wound contraction from day 3 to day 11 as compared to the negative diabetic control group. The serum level of anti-inflammatory cytokine (Interleukin-10) and tissue inhibitor metalloproteinase (TIMP) was significantly higher (P < 0.001), while the level of pro-inflammatory cytokines (tumor necrosis factor-α, Interleukin-6) and matrix metalloproteinases (MMP-2, MMP-9) was significantly lower (P < 0.001) in hydrogels treatment groups as compared to diabetic control group. Although all the hydrogels showed effective results, however the best results were shown by 4 % sericin+4 % banyan+4 % onion based hydrogel. It can be concluded that Sericin based hydrogel enriched with banyan and onion extracts can be used as an effective remedy for the treatment of diabetic wounds due to their high healing and regenerative properties.

Antioxidant Efficacy of Green-Synthesized Silver Nanoparticles Promotes Wound Healing in Mice.

Developing an efficient and cost-effective wound-healing substance to treat wounds and regenerate skin is desperately needed in the current world. Antioxidant substances are gaining interest in wound healing, and green-synthesized silver nanoparticles have drawn considerable attention in biomedical applications due to their efficient, cost-effective, and non-toxic nature. The present study evaluated in vivo wound healing and antioxidant activities of silver nanoparticles from Azadirachta indica (AAgNPs) and Catharanthus roseus (CAgNPs) leaf extracts in BALB/c mice. We found rapid wound healing, higher collagen deposition, and increased DNA and protein content in AAgNPs- and CAgNPs (1% w/w)-treated wounds than in control and vehicle control wounds. Skin antioxidant enzyme activities (SOD, catalase, GPx, GR) were significantly (p < 0.05) increased after 11 days CAgNPs and AAgNPs treatment. Furthermore, the topical application of CAgNPs and AAgNPs tends to suppress lipid peroxidation in wounded skin samples. Histopathological images evidenced decreased scar width, epithelium restoration, fine collagen deposition, and fewer inflammatory cells in CAgNPs and AAgNPs applied wounds. In vitro, the free radical scavenging activity of CAgNPs and AAgNPs was demonstrated by DPPH and ABTS radical scavenging assays. Our findings suggest that silver nanoparticles prepared from C. roseus and A. indica leaf extracts increased antioxidant status and improved the wound-healing process in mice. Therefore, these silver nanoparticles could be potential natural antioxidants to treat wounds.

Matrix remodeling associated 7 proteins promote cutaneous wound healing through vimentin in coordinating fibroblast functions

Wound healing depends largely on the remodeling of the extracellular matrix around and reorganization of tissue-resident cells. Matrix remodeling associated 7 (MXRA7) is a member of the matrix remodeling-associated gene family and is involved in matrix remodeling-associated processes, such as inflammatory neovascularization, liver injury, and autoimmune skin disease. To investigate whether and how MXRA7 participate in cutaneous wound healing, an ear-punching model was utilized in wild-type (WT) and MXRA7-deficient mice, and the dermal fibroblasts from these mice were further studied in vitro. Results showed that the MXRA7 deficiency impaired the wound healing process in mice. Quantitative PCR indicated that lack of MXRA7 impaired the expression of several extracellular matrix genes (e.g., MMP-2) and inhibited signaling pathways (e.g., STAT3) in healing ear tissues. In in vitro culture system, migration, contraction, or proliferation of fibroblasts was impaired upon MXRA7 deficiency. Pull-down and mass spectrum assay revealed that vimentin was among the proteins that bound MXRA7 proteins in cells, and further investigations indicate MXRA7 was an autocrine factor in fibroblasts that involved vimentin in certain ways, such as JNK and STAT3/STAT5 signaling pathways in our study. In conclusion, MXRA7 proteins promote wound healing through vimentin in coordinating fibroblast functions.

Integrating supercapacitor with sodium hyaluronate based hydrogel as a novel All-In-One wound Dressing: Self-Powered electronic stimulation

Constructing the electron transport pathway in a conductive gel membrane wound dressing could promote wound healing, but it always needs an external power supply that bright much inconvenience in clinical practice. In this paper, we design a novel all-in-one self-powered electronic stimulated wound dressing that integrating supercapacitor with sodium hyaluronate based hydrogel. The supercapacitor layer provides the required continuously electrical energy for the wound-dressing layer, where sodium hyaluronate is used as substrate material in both layers for forming the advanced all-in-one structure. During the course of clinical treatment, the electrical stimulation self-powered by supercapacitor would enable patients to perform electrical stimulation wound treatment anytime and anywhere no need on the back ward of a hospital. At the same time, introducing sodium hyaluronate as the active substance and polyelectrolyte would promote cell proliferation and accelerate wound healing, and improve electrochemical performance of supercapacitors. The all-in-one wound dressing has good mechanical properties, high water absorption capacity, and excellent biocompatibility to meet the practical requirements of clinical wound dressings. The supercapacitor layer in the all-in-one wound dressing has good electrochemical performance for charging and discharging before and after usage for wound treatment, and the wound dressing layer enhances the proliferative activity of NIH3T3 cells and accelerate the wound healing process in mice under the action of electrical stimulation provided by the supercapacitor. This study demonstrates that the all-in-one wound dressing would be an attractive candidate for portable wound healing, and broaden the scope of flexible electronics for biomedical applications.

Lack of transient receptor potential ankyrin 1 (TRPA1) retards cutaneous wound healing in mice: A preliminary study

Wound healing is an important process in various diseases, and elucidating the underlying mechanism is essential for developing therapeutic strategies. We investigated whether the loss of transient receptor potential ankyrin 1 (TRPA1) affects the cutaneous wound healing process in mice. We assessed the formation of granulation tissue by myofibroblasts and macrophages, re-epithelialization, and related gene expression. TRPA1-null (KO) and wild-type (WT) C57BL/6 mice were used for establishing the wound model. Two round full-thickness excision wounds (diameter, 5.0 mm) were produced in the dorsal skin of mice under general anesthesia. After specific intervals, healing was evaluated using macroscopic observation, histology, immunohistochemistry, and real-time reverse transcription-polymerase chain reaction (RT-PCR). TRPA1 KO retarded the formation of granulation tissue and re-epithelialization in the healing of cutaneous wound. Furthermore, TRPA1 KO suppressed the appearance of myofibroblasts, macrophage infiltration, and mRNA expression of αSMA, F4/80, and Col-1α2. These findings indicate that TRPA1 is required for cutaneous wound healing in mice. The lack of TRPA1 retards macrophage infiltration and the subsequent fibrotic tissue formation, which might further impair the fibrogenic behavior of fibroblasts.

Evaluation of the alcoholic extract of Dipteryx alata Vogel almonds and bark in skin wound healing in C57BL6 mice

ABSTRACT The aim of this study was to evaluate the topical application of alcoholic extracts of Dipteryx alata Vogel almonds and bark in skin wound healing in mice. Fifty-four C57BL/6 mice were equally distributed into three groups: Control, Almond, and Bark. A 9 mm skin fragment was resected from the dorsal region of the animals’ thorax. The wounds were submitted to topical application of base cream (vehicle), 10% hydroalcoholic almond extract, or bark extract twice a day. Macroscopic, histological, and immunohistochemical evaluations were conducted on the 7th, 14th, and 21st postoperative days. No significant difference was observed regarding skin wound area among groups, with the parameter presenting only a temporal effect on healing (p&gt;0.05). The almond and control groups exhibited more intense collagenization than the bark group (p&lt;0.05). Dipteryx alata Vogel showed to be inert in the wound healing process in mice.

Effect of Carica papaya Extract toward Incised Wound Healing Process in Mice (Mus musculus) Clinically and Histologically.

Wound healing entails a sequence of complex biological processes, which is a protective function of the body that focuses on a quick recovery. Reducing wound healing time is crucial in a wound as it lowers the chance of infection and decreases complications and costs. Papaya extract was obtained by a maceration method. It contains papain enzyme, flavonoid, saponin, and alkaloid, which act as an anti-inflammatory, astringent substance, vasodilator, antioxidant, analgesic, with antifungal, and antibacterial properties, and increase the collagen synthesis. This study aimed to assess the effect of Carica papaya extract application toward incised wound healing process in mice (Mus musculus) clinically and histologically. This experimental laboratory study was performed using 24 mice weighing between 30 and 40 grams and 12 and 14 weeks of age as experimental animals. Each group was incised along 5 mm at the labial gingiva under both of mandible anterior teeth with a depth reaching alveolar bone. Papaya extract was applied topically in the morning and evening for 14 days. The clinical result was obtained by assessing the length of wound closure measured every day for 14 days. Based on the statistic test result, it showed that the papaya extract has a significant effect (p ≤ 0.05) toward the healing process of an incised oral wound in mice. Histologically at day 14, 75% concentration papaya extract showed perfect epithelial layer and fibrillation.

The impact of sex hormones on genital wound healing in mice: a comparative study

The effects estrogen and testosterone have on penile wound healing are still uncertain. This study evaluated the effects of these hormones on the wound healing process of penile and non-penile skin in wild-type (Mus musculusspecies) 4-5-week-old mice. Seventy wild-type Mus musculusspecies were randomly assigned to four groupscontrol (n=17), 1-week post-operative topical estrogen (n=18), 1-week pre-operative testosterone (n=17), and immediate post-operative testosterone (n=18). Incisions were made on the ventrum of the penis and dorsal neck skin. On post-operative day 3, 7, and 14, incision sites were harvested. Evaluation was performed grossly for postsurgical penile edema and histologically for inflammatory cell concentration, presence of fibrinopurulent materials and distribution of collagen-fibroblastic cells. Each treatment group was compared at the three post-operative time points using the Fisher-Freeman--Halton exact test. CD34 and androgen receptor immunohistostaining was performed for between-group differences to assess microvascular density or vasodilatation and androgen receptor upregulation. In this study, the experiment noted significant penile edema on post-operative day 7 in the testosterone groups, whereas less edema in the estrogen group (P=0.010; Figure). On histologic evaluation of the penile wounds, a significantly increased inflammatory cell concentration was noted for both pre-operative and post-operative testosterone groups on post-operative day 14 (P=0.023). The estrogen group revealed significantly increased fibrinopurulent material on the 3rd and 7th post-operative days (P=0.045 and P=0.005, respectively). No significant between-group differences in the collagen-fibroblastic distribution were noted over the three-time phases. On histologic evaluation of the skin wounds, no significant differences were noted between the groups for inflammatory cell concentration and presence of fibrinopurulent materials. However, compared with the testosterone treatment groups, a significant higher collagen-fibroblast distribution was noted in the estrogen groups on post-operative day 3 and 14 (P=0.001 and P=0.044,respectively). Sex hormones, when given peri-operatively, may affect the wound healing process in mice. Testosterone appears to stimulate a prolonged inflammatory effect on penile wounds. Conversely, estrogen induces a fibrinopurulent congregation early in the penile wound healing process. For general skin healing, estrogen induces earlier collagen and fibroblast distribution, whereas testosterone has a delayed effect. The findings of this study should be further investigated in larger animal model with longer follow-up period.

Anti-inflammatory activity of Jatropha curcas Linn. latex in cream formulation on CD68 expression in mice skin wound.

Aim:The purpose of the present study was to determine the potential of Jatropha curcas latex in the cream formulation on CD68 immune expression (macrophages) during inflammatory phase wound healing process in mice skin.Materials and Methods:Amount of 12 two-months-old male mice were used between 30 and 40 g. To surgical procedures, wound skin incision was performed 2.0 cm in length until subcutaneous on the paravertebral of each animal. The treatment was carried under locally anesthetized with procaine cream. The mice were allotted into four groups of each, entire surface of each group wound covered by base cream control, sulfadiazine 0.1% cream, J. curcas latex cream 10% and, 15%, respectively. All experiments were performed twice a day for 3 days. The wound healing was assayed in stained histological sections in immunohistochemical of the wounds. CD68 expression was investigated under a microscope.Results:The results showed that the cream from the 10% and 15% latex of J. curcas revealed moderate immune reaction to CD68 on wound healing.Conclusion:We concluded that the latex cream of J. curcas possesses anti-inflammatory activity in wound healing process of mice skin.

In Vitro Antibacterial Activity of Spanish Moss (Tillandsia usneoides) Crude Extract Against Skin Infection in Wound Healing

Wound healing is a dynamic phenomenon that results in the restoration of anatomic continuity and function on which can be delayed by pathogenic bacteria. This research was designed to explore the antimicrobial efficacy of Tillandsia usneoides against skin infections in wound healing. Physical and chemical evaluations were done through phytochemical screening and thin layer chromatography. The effect of methanolic, ethanolic and aqueous extracts of Tillandsia usneoides against pathogenic bacteria were evaluated on antimicrobial activities using disc diffusion and broth dilution susceptibility assay. The excision bioassay analysis was used in examining the wound healing process in mice. The result of the qualitative phytochemical screening showed the presence of flavonoids and alkaloids. Thin layer chromatography revealed a high Rf value for flavonoids (0.75mm) and alkaloids (0.60mm). The antibacterial assay showed a high zone of inhibition (ZI) for both methanolic extract (&gt;23mm, &gt;22mm and &gt;20mm) and ethanolic extract (&gt;22mm, &gt;22mm and &gt;17mm) for P.aeruginosa, S.aureus and S.epidermis respectively. Resistance against aqueous extract was observed based on the lowest zone of inhibition ( less than 4mm). Gentamicin was used as the positive control (&gt;28mm) and DMSO as the negative control. The minimum inhibitory concentration and minimum bactericidal concentration results confirmed that methanolic and ethanolic extracts restrained the growth of tested bacteria in the range of 125 to 500mg/mL and showed bactericidal efficacy. Wound healing assay indicated that methanolic extract had a higher potency of wound closure (12 days; less than 1mm) compared to ethanolic and aqueous extracts (13days; &gt;1.5mm and 13days: &gt;1.8mm respectively). Povidone-Iodine was used as the gold standard (15days; less than 2mm) in the study. In conclusion, methanolic extract of T. usneoides has a great potential with regard to its antimicrobial and wound healing activity to be developed as a novel drug in the future.

Aktivitas Penyembuhan Luka Sediaan Topikal Ekstrak Bawang Merah (Allium cepa) terhadap Luka Sayat Kulit Mencit (Mus Musculus) (THE ACTIVITY OF TOPICAL EXTRACT OF ONIONS (ALLIUM CEPA) ON WOUND HEALING PROCESS IN MICE (MUS MUSCULUS))

Wound healing is a physiological response of the body to restore continuity, structure and function ofthe injured tissue. Onion is one of the plants that are empirically used by the community to heal wounds.The purpose of this study was to observe the effect of topical extract of onions (Allium cepa) on woundhealing process in mice (Mus musculus) strain BalbC. This study used the posttest-only control groupdesign with completely randomized design (CRD). The samples were 12 male mice with weight ranged of22-32 g divided into four treatments; i.e.: Vaseline, topical extract of onion 5%, topical extract of onion30% and topical extract of onion 55% with 3 replications. Wound healing evaluated macroscopically toobserve hyperemia, wound contraction, granulation, crusting and pus production; and microscopically bycounting the number of fibroblasts on day 10. Hyperemia, granulation, crusting and pus production wereanalyzed descriptively. Wound contraction and the number of fibroblasts were analyzed using ANOVA(p<0.05) and followed with Duncan’s test (p<0,05). Descriptive observations obtained hyperemia lasteduntil day 3, granulation in wounds used topical extract of onion 30% and 55% were faster than the other,crusting lasted until day 6 and the production of pus was not found in any treatment. Statistical testresults showed that topical extract of onion 55% significantly affected wound contraction and topicalextract of onion 30% and 55% significantly affected maturation, which characterized by the decreasednumber of fibroblasts. The results of this study showed that topical extract of onion had significant effect(p<0.05) on wound healing and the effect was in line with the increased concentration of the onion extract.

Involvement of DPP IV/CD26 in cutaneous wound healing process in mice.

Dipeptidyl peptidase IV (DPP IV/CD26) is a widely distributed multifunctional protein that plays a significant role in different physiological as well as pathological processes having a broad spectrum of bioactive substrates and immunomodulative properties. It has potential influence on different processes crucial for wound healing, including cell adhesion, migration, apoptosis, and extracellular matrix degradation. However, despite its known enzymatic and immunomodulative functions, limited data characterize the role of DPP IV/CD26 in cutaneous wound healing mechanisms. The aim of this study was to investigate the process of wound healing in conditions of CD26 deficiency in order to obtain better insights on the role of DPP IV/CD26 in cutaneous regeneration. Experimental wounds were made on the dorsal part of CD26 deficient (CD26-/- ) and wild-type mice (C57BL/6). The process of cutaneous wound healing was monitored on defined time schedule postwounding by macroscopic, microscopic, and biochemical analyses. Obtained results revealed a better rate of wound closure, revascularization and cell proliferation in CD26-/- mice, with enhanced local expression of hypoxia-inducible factor 1α and vascular endothelial growth factor. CD26 deficiency induced prompt macrophage recruitment at the site of skin damage but did not influence mobilization of T-cells in comparison with wild-type mice. CD26-/- mice have significantly higher values of IP-10 in serum and control skins compared with wild-type mice but values in wounds did not differ significantly on days 2, 4, and 7 of wound healing. DPP IV/CD26 activity was found to be decreased 4 days postwounding in serum and 2, 4, and 7 days postwounding in wounds of wild-type animals compared with control skins. These findings contribute to better understanding of wound healing mechanisms and could give a support in finding new therapeutic approaches for wound healing and tissue regeneration.

Transplantation of Cyclic Stretched Fibroblasts Accelerates the Wound-Healing Process in Streptozotocin-Induced Diabetic Mice

Mechanical stimulation is a known modulator of survival and proliferation for many cells, including endothelial cells, smooth muscle cells, and bone marrow-derived mesenchymal stem cells. In this study, we found that mechanical strain prevents apoptosis and increases the adhesive ability of dermal fibroblasts in vitro and thus confers the survival advantage in vivo after transplantation of fibroblasts into the full-thickness wound of diabetic mice. Cyclic stretch at a frequency of 0.5 Hz and maximum elongation of 20% stimulates cellular survival mediated by the activation of extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs), and the serine/threonine kinase Akt (AKT). Stretching of the fibroblasts increases the synthesis of extracellular matrix proteins and the formation of denser focal adhesion structures, both of which are required for fibroblast adhesion. The stretched fibroblasts also upregulate the expression of vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1α (SDF-1α), which enhanced wound healing in vivo. Indeed, preconditioning with mechanical stretch allows better survival of the transplanted fibroblasts, when compared to unstretched control cells, in the wound environment of mice with streptozotocin-induced diabetes and thus accelerates the wound-healing process in these mice.

The epidermal Integrin beta-1 and p75NTR positive cells proliferating and migrating during wound healing produce various growth factors, while the expression of p75NTR is decreased in patients with chronic skin ulcers

Backgroud: More effective treatment strategies are needed for the chronic skin ulcers. Recently, it has been reported that clinical application of stem cells improve wound healing. ObjectiveWe aimed to determine the dynamic time-course movement of epidermal stem cell markers especially p75 neurotrophin receptor (p75NTR) and Integrin beta-1 in wound healing process. Furthermore, we also investigated the presence of these markers in human. MethodsEpidermal Integrin beta-1+ and p75NTR+ cells were counted in wound healing process in mice. Both cells were also counted in human skin specimen obtained from chronic skin ulcers and healthy controls. Growth factor gene expression levels by purified mouse epidermal p75NTR+ cells were also analyzed using real-time RT-PCR. ResultsIntegrin beta-1+ and p75NTR+ cells were proliferated from 3 days after wounding. Reepithelization was completed 7 days after wounding, and the numbers of cells were returned to the baseline levels by 14 days after wounding. Integrin beta-1+ cells were proliferated in the basal layer, and p75NTR+ cells were proliferated in the upper layer of epidermis. In human skin, Integrin beta-1+ and p75NTR+ cells were 81%±12% and 36%±15% of the basal cells, respectively. In patients with chronic skin ulcers, the percentage of Integrin beta-1+ cells in the epidermis was identical to healthy controls. Surprisingly, p75NTR+ cells were significantly decreased in chronic skin ulcer patients (1.2%±2.6%; p<0.0005) compared to healthy controls. Purified mouse epidermal p75NTR+ cells expressed higher transforming growth factor-beta2 and vascular endothelial growth factor-alpha transcripts and lower epidermal growth factor transcripts than p75NTR− cells. ConclusionThese results suggest that Integrin beta-1+ and p75NTR+ cells play an important role in wound healing process, and that p75NTR may be a key molecule and a candidate for new therapeutic target besides preexisting molecules for chronic skin ulcer patients.

Effects of an epidermal growth factor receptor‐based cancer vaccine on wound healing and inflammation processes in murine experimental models

Anti-epidermal growth factor receptor (EGFR) therapies have been proven clinically effective for a variety of epithelial tumours. Vaccination of mice with the extracellular domain (ECD) of autologous EGFR overcomes the tolerance to self-EGFR and has antimetastatic effect on EGFR+ tumour. Because EGF/EGFR-signalling plays an important role in the inflammation stage of wound healing, the main objective of this study was to explore the possible role of murine (m) EGFR-ECD vaccine in the croton-oil-induced ear oedema and wound healing process in mice as autologous experimental models, mimicking the possible post-surgical wound complication in patients treated with human EGFR-ECD/VSSP vaccine. Mice were intramuscularly immunised four times; biweekly with the mEGFR-ECD/VSSP/Mont. Seven days later, an 8 mm diameter, full-thickness skin wound was created on the back of each animal. Immunisation induced a strong specific humoral response against the mEGFR-ECD protein and a DTH dose-response curve but interestingly, animals treated with mEGFR-ECD/VSSP/Mont had similar inflammatory and healing speed responses compared to control ones. These data suggest that application of mEGFR-ECD/VSSP vaccine as a therapeutic approach in cancer patients could not elicit a poor healing process after surgery.

B-1 cells modulate the kinetics of wound-healing process in mice

Wound healing is a complex phenomenon whose mechanisms are not fully understood. Although inflammatory cells are recruited to the site of the lesion there are no reports concerning the participation of B lymphocytes in tissue repair. As demonstrated in our laboratory, B-1 cells migrate to a non-specific inflammatory focus and differentiate into a phagocyte. It has been reported that BALB/ Xid mice are deficient in B-1 cells. Using this model, here we report that BALB/ Xid mice have an increased inflammatory response, a delayed wound-healing process, a prominent neutrophilic infiltration of the lesion, and an increased neovascularization of the lesion as compared with BALB/c and BALB/ Xid reconstituted with B-1 cells. The infiltration of B-1 cells into the wound was demonstrated. As B-1 cells secret and use interleukin 10 (IL-10) as an autocrine growth factor, the possible participation of this interleukin in the kinetics of wound healing was investigated. Results show that C57/BL6 IL-10 KO mice had an increased inflammatory response when compared with C57/BL6 and C57/BL6 IL-10 KO mice reconstituted with B-1 cells, thus suggesting that the observed effects of B-1 cells in the healing process is mediated by this interleukin. However, the mechanisms by which IL-10 influence these phenomena remain to be uncovered.

Tyrosine phosphorylation of EGF‐R and PDGF‐R proteins during acute cutaneous wound healing process in mice

The effect of topical application of epidermal growth factor (EGF) and platelet-derived growth factors (PDGFs) on the levels of EGF-R and PDGF-R proteins and their tyrosine phosphorylation were analyzed during an acute cutaneous wound healing process in mice. The growth factor-treated wounds had optimum levels of receptor proteins as early as day 1 compared with the control, which had only a basal level. Analysis of the tyrosine phosphorylation of the receptor proteins in control and growth factor-treated wounds indicated that they were phosphorylated until day 5 after wounding. Only the mature forms of alpha-PDGF-R and beta-PDGF-R proteins were phosphorylated and not their precursors. Our results show that rapid attainment of maximum levels of growth factor receptor proteins and their tyrosine phosphorylation as early as day 1 and the maintenance of the same until day 3 appear to aid faster and better wound healing. Topical application of PDGF-AA alone did not facilitate the wound healing process and it also antagonized the EGF-medicated wound healing when applied premixed with EGF or within 30 minutes after EGF application. Under these conditions, the receptor proteins were not phosphorylated. Thus, an increased and sustained level of EGF-R and PDGF-R proteins and their tyrosine phosphorylation appear to accelerate the wound healing process.