Upregulation of caveolae-associated structural proteins in the hair follicle bulge of lichen planopilaris and frontal fibrosing alopecia.

Lichen planopilaris (LPP) and frontal fibrosing alopecia (FFA) are primary cicatricial alopecia that cause a major impact on quality of life due to irreversible hair loss and symptoms as itching, burning and pain. They are characterized by permanent loss of hair follicle stem cells (HFSCs) by pathomechanisms still poorly understood, resulting in poor efficacy of currently available treatments. Caveolae are flask-shaped lipid rafts invaginated within the plasma membrane of multiple cell types. Although their role in the HF physiology and pathophysiology is relatively unknown, we have previously demonstrated that the primary structural component of caveolae (caveolin-1 or Cav1) is upregulated in FFA. Thus, we propose to investigate the expression and localization of caveolae-associated structural proteins (Cav1, Cav2, and Cavin-1) and HFSCs (identified by K15) in both LPP and FFA. We analyzed 4 patients with LPP biopsied in affected and non-affected (NA) scalp, 4 patients with FFA biopsied in affected scalp and 4 healthy controls. Affected scalp of LPP and FFA demonstrated increased levels of Cav1 and Cavin-1 compared with HC and LPP-NA. Moreover, Cav1, Cav2 and Cavin1 all exhibit high colocalization with K15 and their expression appears to be negatively correlated, supporting the hypothesis that these proteins are important players in LPP/FFA and may serve as therapeutic targets in future treatments.

Assessment of PD-1 and PD-L1 tissue expression levels in lichen planus patients: a case-control study.

Programmed cell death protein-1 (PD-1) is an immune checkpoint protein, PD-1 interaction with PD ligand-1 (PD-L1) is essential for maintaining immunological tolerance. The study aimed to study and compare the levels of PD-1 and PD-L1 in lesional and nonlesional skin of lichen planus (LP) patients and compare these levels to normal healthy controls to assess their role in the pathogenesis of LP. This case-control study involved 30 patients with LP and 30 healthy age-and sex-matched controls. After clinical assessment of the severity by LP severity index score (LPSI), skin biopsies were taken from lesional and nonlesional skin of LP patients and from normal skin in healthy controls for assessment of the tissue levels of PD-1 and PD-L1 by ELISA. The tissue levels of both PD-1 and PD-L1 were significantly higher in healthy controls than in both lesional and nonlesional skin of LP patients (P < 0.001). Also, significantly higher PD-l and PD-L1 levels in nonlesional skin than in lesional skin of LP patients were reported (P < 0.001). No significant correlations were found between lesional and nonlesional PD-1, PD-L1 levels, or LPSI score. Based on the fact that PD-1/PD-L1 interaction is important to maintain tolerance and protection against autoimmune diseases, in addition to our study results that revealed lower levels of PD-1/PD-L1 in LP skin than in healthy skin, we can conclude that PD-1/PDL-1 may be incriminated in the pathogenesis of LP. ClinicalTrials.govID: NCT04892381.

Increased expression of p16 in both oral and genital lichen planus

BACKGROUND: Lichen Planus, LP, is an inflammatory disease of possible autoimmune origin affecting mainly oral and genital mucosa and skin. According to the WHO oral LP is considered a potentially malignant disorders. The p16 tumour suppressor protein can act as an inhibitor of cyclin dependent kinases 4 and 6 and thus down regulate cell cycle progression. Since the discovery of p16 several studies have evaluated its expression in various forms of human cancers. The aim of this study was to evaluate and compare the expression of p16 in oral and genital LP and corresponding healthy mucosa. MATERIAL AND METHODS: A total of 76 cases of oral LP (OLP), 34 cases of genital LP (GLP), 12 cases of healthy oral and 9 cases of healthy genital mucosa were analysed by the use of immunohistochemistry. RESULTS: Data showed p16 to be highly expressed in both oral and genital LP, higher than in oral (p = 0.000), and genital controls (p = 0.002). CONCLUSIONS: Results suggest that the over-expression of p16 seen in LP play a part in the histopathology of the disease

Evaluation of hbeta;D-1 and hbeta; D-2 levels in saliva of patients with oral mucosal diseases / Evaluación de los niveles de hbeta; D-1 y hbeta;D-2 en la Saliva de pacientes con enfermedades de la mucosa oral

OBJECTIVE: This study aimed to determine a possible correlation between oral mucosal disease and salivary concentrations of the antimicrobial peptides human beta-defensin-1 (hβD-1) and human betadefensin- 2 (hβD-2). METHOD: The present work focussed on the establishment of a reversed phase-high performance liquid chromatography (RP-HPLC) procedure to quantify human beta-defensins (hβD-1 and hβD-2) in saliva samples of patients with oral diseases such as lichen planus (n = 10), Behçet (n = 10) and recurrent apthous stomatitis (n = 10). RESULTS: Linear calibration range for hβD-1 and hβD-2 defensins was 1.67−200 µg mL-1 and 3.13− 100 µg mL-1 with R2 values of 0.9998 and 0.996, correspondingly. The concentration of beta-defensins in saliva was determined by comparing the peak areas of eluted hβD-1 and hβD-2 with that of their standards. The variation of the amount of beta-defensins was evaluated by comparisons of the results obtained from the patients with oral mucosal diseases before and after treatments and the control subjects. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 1.62 µg mL- 1 and 5.39 µg mL-1 for hβD-1 and 0.94 µg mL-1 and 3.13 µg mL-1 for hβD-2, respectively. CONCLUSION: The salivary beta-defensin concentration was significantly higher in patients with oral mucosal diseases than in healthy volunteers; furthermore, in patients with oral mucosal diseases, the concentration was significantly higher before treatment than after treatment.

OBJETIVO: Este estudio tuvo por objeto determinar una posible correlación entre la enfermedad de la mucosa oral y las concentraciones salivales de la beta-defensina humana 1 (hβD-1) y la beta-defensina humana 2 (hβD-2) de los péptidos antimicrobianos. MÉTODO: El presente trabajo estuvo encaminado al establecimiento de un procedimiento de cromatografía líquida de alta eficacia de fase reversa (RP-HPLC) para cuantificar las beta-defensinas humanas (hβD-1 y hβD-2) en muestras de saliva de pacientes con enfermedades orales como el liquen plano (n = 10), Behçet (n = 10), y la estomatitis aftosa recurrente (n = 10). RESULTADOS: El rango de calibración lineal de las defensinas hβD-1 y hβD-2 fue 1.67-200 µg mL-1 y 3.13-100 µg mL-1 con valores R2 de 0.9998 y 996, respectivamente. La concentración de beta-defensinas en la saliva se determinó utilizando el área de sus estándares. La variación de la cantidad de beta defensinas fue evaluada por comparaciones de los resultados obtenidos de los pacientes con enfermedades de la mucosa oral, antes y después de los tratamientos y los sujetos de control. Se halló que el límite de detección (LDD) y el límite de cuantificación (LDC) fueron 1.62 µg mL-1 y 5.39 µg mL- 1 para hβD-1 y 0.94 µg mL-1 y 3.13 µg mL-1 hβD-2, respectivamente. CONCLUSIÓN: La concentración de beta-defensina salival fue significativamente mayor en los pacientes con enfermedades de la mucosa oral que en los voluntarios sanos. Además, en pacientes con enfermedades de la mucosa oral, la concentración fue significativamente mayor antes del tratamiento que después del tratamiento.