The function and survival of melanocytes is regulated by an elaborate network of paracrine factors synthesized mainly by epidermal keratinocytes (KCs). KCs and melanocytes respond to UV exposure by eliciting a tanning response. However, how KCs and melanocytes interact in the absence of UV exposure is unknown. In this study, we demonstrate that after SPRY1 knockout in epidermal KCs, melanocyte stem cells in the hair follicle exit the niche without depleting the pool of these cells. We also found that melanocyte stem cells migrate to the epidermis in a p53/stem cell factor/C-KIT-dependent manner induced by a tanning-like response resulting from SPRY1 loss in epidermal KCs. Once there, these cells differentiate into functional melanocytes. These findings provide an example in which the migration of melanocyte stem cells to the epidermis is due to loss of SPRY1 in epidermal KCs and show the potential for developing therapies for skin pigmentation disorders by manipulating melanocyte stem cells.
Background: Patients with psoriasis may experience an exacerbation in symptoms following COVID-19 infection. After abandoning 'zero COVID' strategies, China experienced a surge of Omicron infections. Objectives: We aimed to investigate psoriasis exacerbation in psoriatic patients with COVID-19, following treatment with three different biologics, adalimumab, secukinumab, and ixekizumab. Methods: We performed a prospective study (n = 209) at our hospital between November 01, 2022, and February 15, 2023. We defined â³ PASI as post-COVID-19 PASI minus pre-COVID-19 PASI. Two endpoints were set in this study. â³ PASI >0 was defined as exacerbation of psoriasis after infection. â³ PASI >3 was defined as a severe exacerbation of psoriasis symptoms after infection. In addition, serum OAS1, OAS2, and OAS3 were also assessed. Results: Results showed that the severity of psoriasis can worsen after COVID-19 infection, and a smaller proportion of patients taking biologics developed worsening psoriasis compared to those not using biologics; however, only the patients taking ixekizumab demonstrated a statistically significant difference (p < 0.05), while those taking adalimumab or secukinumab didn't. What's more, the use of biological agents suppressed the serum OAS2 and OAS3 at low levels and elevated the serum OAS1 level in patients with psoriasis. Conclusions: This study provided new insights into the protective role of biological agents in patients with psoriasis who were infected with COVID-19, and we proposed that psoriatic patients treated with biologics should continue with the treatment during the COVID-19 pandemic.
The skin is the outermost barrier that separates the human body from the external environment. In psoriasis, immune cells reside within or infiltrate the epidermis to form the epidermal (epithelial) immunological microenvironment (EIME) and engage in complex interactions with keratinocytes, nerves, and microbiota. The proposed hypothesis is that psoriasis is a chronic inflammatory disease mainly mediated by a specific inflammatory environment composed of keratinocyte-neuro-immune cell units (KNICUs). These KNICUs arise from the interaction between activated epidermal keratinocytes, nerves, immune cells, and the skin microbiota, forming a complex interaction framework. Multiple units gather to complete the circulatory and amplified loops, consequently serving as a group army to initiate and maintain psoriasis.
Secukinumab is a recombinant, fully human monoclonal anti-IL-17A antibody approved to treat moderate-to-severe psoriasis and psoriatic arthritis. Its effectiveness and safety have been confirmed, but a gradual increase in the secukinumab dosing interval has not been investigated. To assess the feasibility, efficacy, and safety of gradually increasing the secukinumab dosing interval; the interval duration was determined by changes in the Psoriasis Area and Severity Index scores. Patients with moderate-to-severe plaque psoriasis received secukinumab 300 mg subcutaneously at baseline and weeks 0, 1, 2, and 3. At week 4, the improvement from baseline PASI guided the next injection time until week 36. In total, 83 patients were recruited. PASI 75 was achieved by 80%, 96%, and 95% of patients at weeks 4, 12, and 36, respectively. PASI 90 was achieved by 54%, 95%, and 84% of patients at weeks 4, 12, and 36, respectively. PASI 100 was achieved by 28%, 89%, and 68% of patients at weeks 4, 12, and 36, respectively. The average PASI score (1.05 ± 1.83) was significantly lower at week 36 than at baseline. Most patients reached PASI 75 at week 36 in our modified study. This study may provide information for future biotherapies.
Antibodies, Monoclonal , Psoriasis , Humans , Prospective Studies , Antibodies, Monoclonal/adverse effects , Severity of Illness Index , Treatment Outcome , Double-Blind Method , Psoriasis/diagnosis , Psoriasis/drug therapy
Background: Treatment for pediatric psoriasis is challenging because of the lack of real-world evidence, especially for biological therapies. Objectives: This study evaluated the efficacy and safety of biologics in children with psoriasis based on real-world evidence. Methods: Pediatric psoriasis patients aged <18 years who were treated with biologics in our hospital (2020-2022) were prospectively analyzed. Patients treated with adalimumab, secukinumab, or ixekizumab were followed up for at least 16 weeks, and 22 of 38 patients completed the 52-week observation period. Dermatologist raters were blinded to ensure the reliability of the PASI, BSA, and PGA score assessments. PASI 75 or PGA 0/1 at week 12 represented an efficient indicator. Results: Thirty-eight patients (20 males and 18 females; median age, 12.6 ± 4.1 years) were enrolled, and none were lost to follow-up. All participants were diagnosed with psoriasis, including plaque psoriasis (n = 36), nail psoriasis (n = 1), and pustular psoriasis (n = 1). Within 12 weeks, all patients achieved scores above PASI 75 and PGA 0/1. The average time to reach PASI 75 was 4.3 ± 2.0, 3.2 ± 1.8, and 2.4 ± 0.4 weeks in patients using adalimumab, secukinumab, and ixekizumab, respectively, and, 27.2% (3/11), 86.4% (19/22), and 75.0% (3/4) of these patients achieved PASI 100 at week 12, respectively. Moreover, 18 of 20 patients with plaque psoriasis maintained ≥PASI 75 after 52 weeks. The most commonly reported adverse effect was upper respiratory tract infection, and no severe adverse effects were reported. Conclusions: Our real-world data demonstrated the safety and effectiveness of adalimumab, secukinumab, and ixekizumab in children with psoriasis.
Psoriasis is a chronic multisystem inflammatory disease that affects ~0.1-1.5% of the world population. The classic cutaneous manifestation of psoriasis is scaly erythematous plaques, limited or widely distributed. Moreover, psoriasis could be associated with comorbidities like psoriatic arthritis, metabolic syndrome, diabetes, cardiovascular disease, nephropathy, bowel disease, and brain diseases. In this review, we suggest that psoriasis should be classified as cutaneous psoriasis or systemic psoriasis and propose the classification for distinction. This would help to better understand and manage psoriasis.
