LL-37

Many patients with venous leg ulcers do not reach complete healing with compression treatment alone, which is current standard care. This clinical trial HEAL LL-37 was a phase IIb double-blind, randomized, placebo-controlled study, with the aim to evaluate the efficacy and safety of a new drug LL-37 for topical administration, in combination with compression therapy, in 148 patients suffering from hard-to-heal venous leg ulcers. The study had three arms, consisting of two groups treated with LL-37 at concentrations of 0.5 or 1.6 mg/mL, and a placebo cohort. Patients had a mean age of 67.6 years, a median ulcer duration of 20.3 months, and a mean wound size at the time of randomization of 11.6 cm2 . Efficacy analysis performed on the full study population did not identify any significant improvement in healing in patients treated with LL-37 as compared with the placebo. In contrast, a post hoc analysis revealed statistically significant improvement with LL-37 treatment in several interrelated healing parameters in the subgroup of patients with large target wounds (a wound area of at least 10 cm2 at randomization), which is a known negative prognostic factor for healing. The study drug was well tolerated and safe in both dose strengths. In summary, this clinical trial did not detect any significant differences in healing of venous lower leg ulcers in the entire study cohort comparing patients treated with LL-37 versus placebo. A subgroup analysis provided an interesting observation that LL-37 could offer a treatment benefit in patients with large ulcers, exigently warranting a further study adequately powered to statistically assess the treatment outcome in this patient group.

Background. In vivo studies show that LL-37 inhibits the progression of atherosclerosis and predicts a lower risk of recurrent ischemia in patients with acute myocardial infarction (AMI), which could be mediated by the modulation of lipid metabolism. The current study aimed to investigate the effects of various lipid contents on the prognostic impacts of LL-37 in patients with AMI. Methods. A total of 1567 consecutive AMI patients were prospectively recruited from March 2017 to January 2020. Patients were firstly stratified into two groups by the median level of LL-37 and then stratified by levels of various lipid contents and proprotein convertase subtilisin/kexin type 9 (PCSK9). Cox regression with multiple adjustments was performed to analyze associations between LL-37, lipid profiles, PCSK9, and various outcomes. The primary outcome was major adverse cardiovascular event (MACE), a composite of all-cause death, recurrent MI, and ischemic stroke. Results. During a median follow-up of 786 (726−1107) days, a total of 252 MACEs occurred. A high level of LL-37 was associated with lower risk of MACE in patients with elevated lipoprotein(a) (≥300 mg/L, hazard ratio (HR): 0.49, 95% confidence interval (CI): 0.29−0.86, p = 0.012) or PCSK9 levels above the median (≥47.4 ng/mL, HR: 0.57, 95% CI: 0.39−0.82, p < 0.001), which was not observed for those without elevated lp(a) (<300 mg/L, HR: 0.96, 95% CI: 0.70−1.31, p = 0.781, pinteraction = 0.035) or PCSK9 (<47.4 ng/mL, HR: 1.02, 95% CI: 0.68−1.54, p = 0.905, pinteraction = 0.032). Conclusions. For patients with AMI, a high level of LL-37 was associated with lower ischemic risk among patients with elevated lp(a) and PCSK9.

Wound healing in DFU (diabetic foot ulcer) has prolonged inflammation phase and defective granulation tissue formation. LL-37 has antimicrobial property, induces angiogenesis, and keratinocyte migration and proliferation. This study analyzes the efficacy of LL-37 cream in enhancing wound healing rate and decreasing the levels of IL-1α, TNF-α, and the number of aerobic bacteria colonization in DFU with mild infection. This study was conducted from January 2020 to June 2021 in Jakarta. Subjects were instructed to apply either LL-37 cream or placebo cream twice a week for 4 weeks. Wounds were measured on days 7, 14, 21, and 28 and processed with ImageJ. The levels of LL-37, IL-1α, and TNF-α from wound fluid were measured using ELISA. The number of aerobic bacteria colonization was counted from the isolate grown in culture. The levels of LL-37 in DFU at baseline were equally low in both groups which were 1.07 (0.37-4.96) ng/mg protein in the LL-37 group and 1.11 (0.24-2.09) ng/mg protein in the placebo group. The increase in granulation index was consistently greater in the LL-37 group on days 7, 14, 21, and 28 (p = 0.031, 0.009, 0.006, and 0.037, respectively). The levels of IL-1α and TNF-α increased in both groups on days 14 and 21 (p > 0.05). The decrease in the number of aerobic bacteria colonization was greater in the LL-37 group on days 7, 14 and 21, but greater in the placebo group on day 28 (p > 0.05). In conclusion, LL-37 cream enhanced the healing rate of DFU with mild infection, but did not decrease the levels of IL-1α and TNF-α and the number of aerobic bacteria colonization. This trial is registered at ClinicalTrials.gov, number NCT04098562.

Recombinant LL-37 Lactococcus lactis (Oral LL-37) was designed to prevent progression of COVID-19 by targeting virus envelope, however, effectiveness and safety of Oral LL-37 in clinical application was unclear. A total of 238 adult inpatients, open-labelled, randomized, placebo-controlled, single-center study was conducted to investigate the primary end points, including negative conversion time (NCT) of SARS-CoV-2 RNA and adverse events (AEs). As early as intervened on 6th day of case confirmed, Oral LL-37 could significantly shorten NCT (LL-37 9.80 ± 2.67 vs. placebo 14.04 ± 5.89, p < 0.01). For Oral LL-37, as early as treated in 6 days, the adjusted hazard ratio (HR) for a primary event of nucleic acid negative outcome was 6.27-fold higher than 7-day-later (HR: 6.276, 95% confidence interval [CI]: 3.631-10.848, p < 0.0001), and the adjusted HR of Oral LL-37 within 6 days is higher than placebo (HR: 2.427 95% CI: 1.239-4.751, p = 0.0097). No severe AEs were observed during hospitalization and follow-up investigation. This study shows that early intervention of Oral LL-37 incredibly reduces NCT implying a potential for clearance of Omicron BA.5.1.3 without evident safety concerns.

PURPOSE: To determine whether low serum vitamin D levels are inversely correlated with clinical parameters and positively correlated with gingival crevicular fluid (GCF) 25(OH)D3, 1,25(OH)2D3, LL-37 and tumor necrosis factor-α (TNF-α) levels in periodontitis patients with well-controlled type-2 diabetes (T2DM). MATERIALS AND METHODS: Twenty-six well-controlled T2DM patients with periodontitis and Vitamin D insufficiency (Vit.D-IS group), and 15 well-controlled T2DM patients with periodontitis and Vitamin D sufficiency (Vit.D-S group) were included. Papilla bleeding index, bleeding on probing (BOP), supragingival plaque, clinical attachment level (CAL) and probing depth (PD) were evaluated. GCF total amounts of 25(OH)D, 1,25(OH)2D3, LL-37 and TNF-α were analyzed by ELISA. Serum 25(OH)D3 levels were determined using liquid chromatography tandem-mass spectrometry. RESULTS: Whole mouth CAL and BOP scores were higher in the Vit.D-IS group than those of Vit.D-S group (P=0.038, P=0.048, respectively). Whole mouth PD and plaque values were comparable in both groups. Differences were not detected in GCF 25(OH)D3, 1,25(OH)2D3, LL-37 and TNF-α levels between Vit.D-IS and Vit.D-S groups. Serum 25(OH)D3 levels were adversely associated with CAL and BOP scores (P=0.018, P=0.049, respectively). Also, GCF 1,25(OH)2D3 total amounts were positively related with GCF LL-37 total amounts (P=0.0001). CONCLUSION: Serum 25(OH)D3 insufficiency was related to periodontal inflammation and destruction in periodontitis patients with well-controlled T2DM. However, GCF 25(OH)D3, 1,25(OH)2D3, TNF-α and LL-37 total amounts were not correlated with serum vitamin D levels. We have opinion that obtaining and maintenance of periodontal health should be included in the diabetic treatment protocol in Vitamin D deficient patients with periodontitis and well-controlled T2DM.

BACKGROUND: Capsular contracture is the most common complication following breast implant placement. Cathelicidin LL-37 is a cationic peptide involved in innate immunity. Initially investigated for its antimicrobial role, it was found to have pleiotropic activities, such as immunomodulation, angiogenesis stimulation, and tissue healing. The aim of the study was to investigate the expression and localization of LL-37 in human breast implant capsules and its relationship with capsular formation, remodeling, and clinical outcomes. METHODS: The study enrolled 28 women (29 implants) who underwent expander substitution with definitive implant. Contracture severity was evaluated. Specimens were stained with hematoxylin and eosin, Masson trichrome, immunohistochemistry, and immunofluorescence for LL-37, CD68, α-smooth muscle actin, collagen type I and type III, CD31, and Toll-like receptor-4. RESULTS: LL-37 was expressed in macrophages and myofibroblasts of capsular tissue in 10 (34%) and nine (31%) of the specimens, respectively. In eight cases (27.5%), it was expressed by both macrophages and myofibroblasts of the same specimen. In infected capsules, expression by both cell types was found in all (100%) specimens. LL-37 expression by myofibroblasts positively correlated with its expression by macrophages ( P < 0.001). Moreover, LL-37 expression by macrophages of periexpander capsules negatively correlated with the severity of capsular contracture on definitive implants ( P = 0.04). CONCLUSIONS: This study demonstrates the expression of LL-37 in macrophages and myofibroblasts of capsular tissue and its negative correlation with the severity of capsular contracture following permanent implant placement. Expression or up-regulation of LL-37 may be involved in myofibroblast and macrophage modulation, thus playing a role in the pathogenic fibrotic process underlying capsular contracture. CLINICAL RELEVANCE STATEMENT: This is the first study to demonstrate LL37 expression in capsular tissue and to hypothesize its role in contracture and as a prognostic marker for contracture severity. If confirmed, medical strategies or implant coating could be implemented to reduce the risk of contracture for high-risk patients.