ll 37, human

LL-37, Human is a 37-residue, amphipathic, cathelicidin-derived antimicrobial peptide, which exhibits a broad spectrum of antimicrobial activity.

Human LL-37 is a 37 amino acid cationic (6+) peptide and has been widely studied. LL-37 penetrates the bacterial membrane and forms pores in the membrane.

LL-37, Human acetate(154947-66-7 free base) 是一种 37 个残基、两亲性、cathelicidin 衍生的抗菌肽，具有广谱的抗菌活性。

LL-37 (18-37) 是 LL-37 的一种抗菌肽片段。对S. aureus和C. albicans具有活性，最小致死浓度分别为4 µM 和10 µM。在10到50 µM 的浓度范围内，它还能抑制E. histolytica营养体的生长。

KKL-40 是一种小分子抑制剂，专门针对反式转录过程，能够有效抑制甲氧西林敏感和耐药的金黄色葡萄球菌 (S. aureus)，以及包括耐万古霉素的屎肠球菌、枯草芽孢杆菌和化脓性链球菌在内的其他革兰氏阳性病原体。KKL-40 与人类抗菌肽 LL-37 协同作用可抑制金黄色葡萄球菌，但与达托霉素、卡那霉素或红霉素等其他抗生素之间没有协同效应。反式转录是一种极端的重新编码形式，KKL-40 能抑制该过程，同时对 HeLa 细胞无毒。

β-Defensin-2 is a peptide with antimicrobial properties that protects the skin and mucosal membranes of the respiratory, genitourinary, and gastrointestinal tracts.1It inhibits the growth of periodontopathogenic and cariogenic bacteria, includingP. gingivalisandS. salivarius.2β-Defensin-2 (30 μg/ml) stimulates gene expression and production of IL-6, IL-10, CXCL10, CCL2, MIP-3α, and RANTES by keratinocytes.3It also stimulates calcium mobilization, migration, and proliferation of keratinocytes when used at concentrations of 30, 10, and 40 μg/ml, respectively. β-Defensin-2 induces IL-31 production by human peripheral blood-derived mast cellsin vitrowhen used at a concentration of 10 μg/ml and by rat mast cellsin vivofollowing a 500 ng intradermal dose.4Expression of β-defensin-2 is increased in psoriatic skin and chronic wounds.5,6 1.Lehrer, R.I.Primate defensinsNat. Rev. Microbiol.2(9)727-738(2004) 2.Ouhara, K., Komatsuzawa, H., Yamada, S., et al.Susceptibilities of periodontopathogenic and cariogenic bacteria to antibacterial peptides, β-defensins and LL37, produced by human epithelial cellsJ. Antimicrob. Chemother.55(6)888-896(2005) 3.Niyonsaba, F., Ushio, H., Nakano, N., et al.Antimicrobial peptides human β-defensins stimulate epidermal keratinocyte migration, proliferation and production of proinflammatory cytokines and chemokinesJ. Invest. Dermatol.127(3)594-604(2007) 4.Niyonsaba, F., Ushio, H., Hara, M., et al.Antimicrobial peptides human β-defensins and cathelicidin LL-37 induce the secretion of a pruritogenic cytokine IL-31 by human mast cellsJ. Immunol.184(7)3526-3534(2010) 5.Huh, W.-K., Oono, T., Shirafuji, Y., et al.Dynamic alteration of human β-defensin 2 localization from cytoplasm to intercellular space in psoriatic skinJ. Mol. Med. (Berl.)80(10)678-684(2002) 6.Butmarc, J., Yufit, T., Carson, P., et al.Human β-defensin-2 expression is increased in chronic woundsWound Repair Regen.12(4)439-443(2004)

LL-37 is a cationic and α-helical antimicrobial peptide expressed in human bone marrow, testis, granulocytes, and gingival epithelium and is upregulated in psoriatic lesions. It inhibits growth of Gram-positive E. coli D21 and Gram-negative B. megatarium in a concentration-dependent manner and LL-37 expression is induced in A549 epithelial cells, alveolar macrophages, neutrophils, and monocyte-derived macrophages following M. tuberculosis infection. LL-37 binds sheep erythrocytes coated with S. minnesota Re-LPS and induces agglutination with a minimal agglutinating concentration (MAC) of 12.1 μg/ml. It is a chemoattractant for, and can induce calcium mobilization in, human monocytes, neutrophils, and T cells that naturally express formyl peptide receptor-like 1 (FPRL1) and FPRL1-transfected HEK293 cells. LL-37 (10-15 μM) pretreatment of dengue virus type 2 (DENV-2) reduces its infectivity as well as levels of viral genomic RNA and NS1 antigen. In vivo, LL-37 inhibits cecal ligation and puncture-induced caspase-1 activation and pyroptosis of peritoneal macrophages, reduces levels of the inflammatory cytokines IL-1β, IL-6, and TNF-α, and improves survival in polybacterial septic mice.

LL-37 GKE acetate是具有21个氨基酸的多肽和LL-37的活性结构域，抑制lps诱导的血管一氧化氮产生，对人培养平滑肌细胞溶血和凋亡的毒性小于LL-37，具有抗菌活性和治疗败血症的潜力。

Lugdunin是一种具有抗菌活性的肽类抗生素。该化合物能够通过破坏细菌细胞膜的电位来抑制革兰氏阳性菌的生长，特别是对金黄色葡萄球菌（Staphylococcus aureus）表现出高效能，有效降低其在皮肤和鼻腔的定植能力。此外，Lugdunin还能在人类角质形成细胞和小鼠皮肤中促进LL-37和CXCL8 MIP-2的表达。

LL-37(17-32)为具有生物活性的肽段，为LL-37抗菌肽C末端结构域源自的活性片段。报道显示，LL-37(17-32)能逆转癌细胞系中ABCG2介导的多药耐药性。

CRAMP (140-173) (mouse)，作为人LL-37抗菌肽的同源物，能够抑制LPS诱导的反应，但在BEAS-2B细胞中不与TLR3发生共定位。

Citrullinated LL-37 1cit 是一种Citrullinated形式的 LL-37 肽，保持了针对 human rhinovirus 的抗病毒 (antiviral) 功能，同时对S. aureus 表现出抗菌 (antibacterial) 活性。此外，Citrullinated LL-37 1cit 能够降低 RV1B 诱导的 IL-8、CCL5 和 IL-6mRNA 水平。

Citrullinated LL-37 2cit是瓜氨酸化的LL-37肽，在10 μg mL浓度下可减弱LL-37对HRV活性的抑制，并降低LL-37的抗菌效果。此外，Citrullinated LL-37 2cit能显著降低RV1B诱导的IL-8、CCL5和IL-6 mRNA水平，并对HRV诱导的CCL5分泌能力有中度抑制作用。

Citrullinated LL-37 3cit，一种宿主防御肽(HDP)，展现出广泛的免疫调节和抗菌活性，且能有效抑制人鼻病毒(HRV)。

KR-12 human是LL-37的活性片段，对革兰氏阴性菌具有显著抗菌活性。KR-12 human可抑制E. coli K-12的活性，最低抑菌浓度（MIC）为66 μM。

LL-37 FK-13TFA 代表LL-37 FK-13的TFA盐状态.这种化合物主要用作抗菌剂,有效抑制Trichomonas vaginalis.与此同时,LL-37 FK-13 TFA对人类红细胞展示出轻微的溶血性,对人类成纤维细胞的细胞毒性也相对较弱.