Involvement of Epidermis Cell Proliferation in Defense Against Beauveria bassiana Infection

Entomopathogenic fungi Beauveria bassiana can infect many species of insects and is used as a biological pesticide world-wide. Before reaching the hemocoel, B. bassiana has to penetrate the integument which is composed of a thick chitin layer and epidermal cells. Some chitinase, protease and lipase secreted by B. bassiana are probably involved in the fungal penetration of the integument. While microscopic proof is needed, it is difficult to locate the precise infection sites following the traditional method of immersion infection. Consequently, we developed a new method to inoculate conidia solution into a single fixed-site on the back of one segment. This fixed-site infection method is pathogenic but it is also dose dependent. Using the fixed-site infection protocol, it is also very convenient to track hyphae inside the cuticle layer by light and transmission electron microscopy. The fact that few hyphae were detected inside the chitin layer after fixed-site infection with mutant ΔBPS8, a protease secreted during fungi germination, indicates that this method is suitable for screening genes involved in penetrating the integument in large scale. We also found that melanization occurs before new hyphae penetrate the chitin layer. Most importantly, we discovered that fungal infection can induce epidermal cell proliferation through DNA duplication and cell division, which is essential for the host to defend against fungal infection. Taken together the fixed-site infection method may be helpful to determine the mechanism of fungal and host interaction in the integument so as to effectively exert fungal biological virulence.

Autologous Lipofilling Improves Clinical Outcome in Patients With Symptomatic Dermal Scars Through Induction of a Pro-Regenerative Immune Response

Background Autologous lipofilling is emerging procedure to augment and possibly reverse dermal scars and to reduce scar-related pain, but its efficacy and mechanisms are poorly understood. Objectives To test the hypothesis that repeated lipografts reverse dermal scars by re-initiation of wound healing. Methods In a prospective, non-placebo controlled clinical study, 27 adult patients with symptomatic scars were given two lipofilling treatments at 3-month intervals. As primary outcome, clinical effects were measured using the patient and observer scar assessment scale (POSAS). Scar biopsies were taken before and after treatments to assess scar remodeling at a cellular level. Results Twenty patients completed the study. Patients’ scars improved after lipofilling. The total POSAS scores (combined patient and observer scores) decreased from 73.2±14.7 points pre-treatment to 46.1±14.0 and 32.3±13.2 after the first and second treatment, respectively. Patient POSAS scores decreased from 37.3±8.8 points to 27.2±11.3 and 21.1±11.4 points, whereas Observer POSAS scores decreased from 35.9±9.5 points, which decreased to 18.9±6.0 and 11.3±4.5 points after the first and second lipofilling treatment, respectively. After each lipofilling treatment, T-lymphocytes, mast cells and M2 macrophages had invaded scar tissue and associated was increased vascularization. In addition, the scar-associated epidermis showed increase in epidermal cell proliferation which was akin to normal skin. Moreover, lipofilling treatment caused normalization of the extracellular matrix (ECM) organization towards that of normal skin. Conclusions Autologous lipofilling improves clinical outcome of dermal scars through the induction of a pro-regenerative immune response, increased vascularization, and epidermal proliferation and remodeling of scar tissue ECM.

Insight into the Metabolite Pattern of Psoriasis: Correlation among Homocysteine, Methionine, and Polyamines

Psoriasis is an incurable dermatological disorder, characterized by increased epidermal cell proliferation. Numerous studies have focused on the modulation of polyamine (PA) metabolism in psoriatic lesions, as well as the relationship between serum homocysteine (Hcy) levels and psoriasis severity. The correlation between Hcy and PA levels has not been investigated, although both of them depend on methionine (Met) loading. The aim of this study was to examine Met, Hcy, and polyamine levels in serum, saliva, lesions, and non-affected skin to investigate the eventual relationship between their levels in skin samples and to assess the correlation of each metabolite among the tested samples. This study was conducted on 24 patients with plaque-form psoriasis vulgaris. The original LC-MS/MS method was used for quantification of analytes. Hyperhomocysteinemia was observed and the serum levels of spermidine (Spd) and spermine (Spm) were also found to be elevated. A significant increase in Met (p < 0.05) and Spm (p < 0.001) concentrations in the psoriatic plaques were found, when compared to the non-affected skin. Significant correlations were established between all polyamines levels and between methionine and spermine in both types of cutaneous samples. This study illustrates the tight relationship between Met and Polyamine levels in epidermis of psoriatic patients. Our results could be helpful in psoriasis treatment, highlighting the importance of the balanced protein diet and intake of vitamins B12 and B9.

Intralesional Vitamin D3 Injection in the Treatment of Recalcitrant Warts: A Novel Proposition

Background: Verruca vulgaris (viral warts) is a fairly common condition with a plethora of treatment options having variable success rates. Recalcitrant warts are refractory to treatment with often disappointing response and high recurrence rates. Lately, treatment with intralesional injections has gained momentum due to its effectiveness in clearing warts by stimulating the cell-mediated immunity. Vitamin D, when applied topically, regulates epidermal cell proliferation and is involved in the formation of antimicrobial peptides. We have attempted to use vitamin D3 to exploit its reported action as an immunotherapeutic molecule in addition to its topical effects. To our knowledge, there are no reports of intralesional vitamin D3 injections used in the treatment of extragenital recalcitrant warts. Methods: Sixty-four patients with recalcitrant warts of varying sizes and duration were included in the study. About 0.2- to 0.5-mL vitamin D3 solution (600,000 IU, 15 mg/mL) was injected to the base of the wart. A maximum of 5 warts were injected per session at 3-week intervals until resolution or for a maximum of 4 treatments. Patients were followed up for 6 months after the last injection to detect any recurrence. Results: Sixty patients completed the study. Complete response was seen in 54 of 60 (90%), partial response in 4 of 60 (6.66%), and no response in 2 of 60 (3.33%). The average number of injections required to achieve a complete resolution was 3.66. Complete resolution of distant warts was noticed in all patients. Conclusions: Intralesional vitamin D3 is a safe, effective, and an inexpensive treatment option for recalcitrant warts.