The Developmental & Molecular Requirements for Ensuring that Human Pluripotent Stem Cell-Derived Hair Follicle Bulge Stem Cells Have Acquired Competence for Hair Follicle Generation Following Transplantation.

When using human induced pluripotent stem cells (hiPSCs) to achieve hair follicle (HF) replacement, we found it best to emulate the earliest fundamental developmental processes of gastrulation, ectodermal lineage commitment, and dermogenesis. Viewing hiPSCs as a model of the epiblast, we exploited insights from mapping the dynamic up- and down-regulation of the developmental molecules that determine HF lineage in order to ascertain the precise differentiation stage and molecular requirements for grafting HF-generating progenitors. To yield an integrin-dependent lineage like the HF in vivo, we show that hiPSC derivatives should co-express, just prior to transplantation, the following combination of markers: integrins α6 and ß1 and the glycoprotein CD200 on their surface; and, intracellularly, the epithelial marker keratin 18 and the hair follicle bulge stem cell (HFBSC)-defining molecules transcription factor P63 and the keratins 15 and 19. If the degree of trichogenic responsiveness indicated by the presence of these molecules is not achieved (they peak on Days 11-18 of the protocol), HF generation is not possible. Conversely, if differentiation of the cells is allowed to proceed beyond the transient intermediate progenitor state represented by the HFBSC, and instead cascades to their becoming keratin 14+ keratin 5+ CD200- keratinocytes (Day 25), HF generation is equally impossible. We make the developmental case for transplanting at Day 16-18 of differentiation-the point at which the hiPSCs have lost pluripotency, have attained optimal expression of HFBSC markers, have not yet experienced downregulation of key integrins and surface glycoproteins, have not yet started expressing keratinocyte-associated molecules, and have sufficient proliferative capacity to allow a well-populated graft. This panel of markers may be used for isolating (by cytometry) HF-generating derivatives away from cell types unsuited for this therapy as well as for identifying trichogenic drugs.

A novel topical combination of minoxidil and spironolactone for androgenetic alopecia: Clinical, histopathological, and physicochemical study.

Topical minoxidil 5% are effective in androgenetic alopecia (AGA). Spironolactone acts as an androgen antagonist by competitively blocking androgen receptors. Studying the effect of topical minoxidil 5% gel and spironolactone gel 1% in management of AGA. The study includes 60 patients diagnosed as AGA; (group I): treated with topical minoxidil gel 5%, (group II): with topical spironolactone gel 1% and group (III) treated with combined minoxidil 5% and spironolactone 1% gel. All patients were followed up monthly throughout the treatment period. Scalp biopsy was taken before and after 12 months. In group I, the clinical response was in 90% of patients with variable degrees in improvement, in group II, the clinical response was in 80% of patients, meanwhile, in group III the clinical response was in all patients (100%). Histopathological examination of skin biopsy after treatment revealed significant increase in anagen hair on the other hand, both telogen and vellus hair was significantly decreased meanwhile, the T/V ratio was significantly increased. The results of this work revealed that topical minoxidil gel 5% and topical spironolactone gel 1% were effective in treatment of AGA, while the combination of two agents was better in treatment.

Hair follicle changes following intense pulsed light axillary hair reduction: histometrical, histological and immunohistochemical evaluation.

Intense pulsed light (IPL) has been used for years in hair reduction; however, no previous studies discussed quantitative histological and immunohistochemical changes of hair follicles after IPL. Accordingly, this study aims to objectively quantify histological and immunohistochemical changes of hair follicles after IPL hair reduction. Right axillae of 21 volunteers were subjected to 6 IPL sessions using Quanta system IPL and evaluated at 1 week and 1 month after last session (i.e., 3 and 4 months from the start of treatment, respectively) in comparison to baseline and left control axillae. Using hair count, histological and immunohistochemical assessment of vertical and serial transverse sections coupled with computerized morphometric analysis, determination of hair reduction percentage, measurement of hair shaft (HS) diameter, calculation of percentage of hair follicle types and quantitative evaluation of PCNA, Ki67 and P53 markers were performed. After IPL, there was significant decrease of hair count, HS diameter, percentage of terminal anagen follicles, terminal/vellus (T/V) ratio, anagen/telogen (A/T) ratio and expression of PCNA and Ki67; however, significant increase of percentage of terminal telogen and total vellus follicles with vellus-like type and P53 expression was identified. So, reduction of hair number and thickness occurred after IPL by induction of telogenesis and miniaturization through decreased hair follicle proliferation and increase in DNA damage that could favor apoptosis.

Fractional Microneedling: A Novel Method for Enhancement of Topical Anesthesia Before Skin Aesthetic Procedures.

BACKGROUND: Skin microneedling or fractional microneedle therapy is a recent approach used for skin rejuvenation or to enhance transdermal delivery of topical medications. OBJECTIVE: The authors evaluated the efficacy of skin microneedling, using an automated device, to enhance the numbing effect of topical anesthesia, used before minimally invasive aesthetic approaches. METHODS: Fifteen patients, looking for treatment of atrophic acne scars, were subjected to randomized split-face study comparing automated fractional skin microneedling (0.5 mm depth) followed by application of topical anesthetic cream (Lidocaine 2.5% + Prilocaine 2.5%) on one side of face, with topical anesthesia alone on the other side, followed by full face fractional microneedling treatment for postacne scars (2.5 mm depth). RESULTS: The treated sides (fractional needling + topical anesthesia) had significantly lower pain scores when compared with the nontreated sides (topical anesthesia alone). The scores of pain sensation, during the whole procedure, were statistically significantly (p < .0001) less on the treated sides (3.10 ± 1.09) of the face when compared with the nontreated sides (5.37 ± 0.99). There was also a statistically significant (p < .0001) difference in pain sensation scores between the 2 sides of the face after horizontal passes, as the mean scores of the treated and nontreated sides were 3.93 ± 0.59 and 6.20 ± 0.41, respectively. LIMITATIONS: The small number of patients, yet the results show a significant difference. CONCLUSION: Application of topical anesthesia for minimally invasive aesthetic procedures can be enhanced with fractional microneedling pretreatment.