UNO 多肽

H-CSPGAKVRC-COOH

H-Cys-Ser-Pro-Gly-Ala-Lys-Val-Arg-Cys-COOH

9

95.2

C₃₆H₆₅N₁₃O₁₁S₂

920.11

固相合成

Tumor-associated macrophages (TAMs) have been linked to the tumor progression and suppress anti-tumor immunity. Number of TAMs in human tumors correlate with a higher tumor grade and shortened survival for several cancer types. In particular, the perivascular macrophages in tumors have been associated with increased tumor angiogenesis, distant metastasis, poor prognosis, and/or the recurrence of tumors after chemotherapy in various forms of cancer. To identify peptides binding the peritoneal cells of 4T1 breast cancer bearing mice, Teesalu and colleagues performed a phage screen by injecting the CX7C peptide library to the peritoneum of tumor-bearing or healthy mice. After 2 h, the peritoneal cells were isolated, the bound phage were rescued by amplification and subjected to high-throughput sequencing. The CSPGAKVRC peptide (UNO) was the most frequent non-truncated peptide in the pool amplified from the tumor-bearing mice. The GSPGAK motif was detected in physiological ligands of CD206, a marker of M2-skewed macrophages. The authors then showed that UNO bound to the CD206, but interestingly the binding required linearity of the UNO peptide. It was concluded that the glutaredoxin system in the tumor microenvironment may contribute to the reduction of the disulfide-bridged UNO. Intravenously injected fluorescent UNO (FAM-UNO) accumulated in the CD206+ macrophages in 4T1 tumors and in sentinel lymph nodes. In addition, FAM-UNO recognized the CD206+ macrophages in several other tumor models such as intracranial glioblastoma (WT-GBM), metastatic melanoma (B16F10), and peritoneal gastric carcinoma (MKN45-P). Moreover, FAM-UNO was shown to guide cargo to CD206+ macrophages and was proposed as a potential sentinel lymph node imaging agent.

一般情况下， UNO 多肽 粉末应该保存在-20甚至-70摄氏度. UNO 多肽 溶解后应该-70摄氏度分装保存，避免反复冻融. 了解更多细节，请查阅手册:多肽溶解及保存指南

• Scodeller P, Simón-Gracia L, Kopanchuk S, Tobi A, Kilk K, Säälik P, et al. Precision Targeting of Tumor Macrophages with a CD206 Binding Peptide. Sci Rep. 2017;7(1):14655

三氟乙酸（Trifluoroacetic acid，简称 TFA）是高效液相色谱（简称 HPLC）纯化过程中常用的反离子。TFA 的存在可能会对肽的净重量、外观及溶解度产生影响，具体如下：

对净重量的影响：TFA 盐会增加产物的总质量。在大多数情况下，肽的含量占总重量的 80% 以上，剩余部分则为 TFA。

对溶解度的影响：TFA 盐通常能提高肽在水溶液中的溶解度。

在生物检测中的影响：对于大多数标准的体外检测，残留的 TFA 水平一般不会造成干扰。但需注意，在高灵敏度的细胞研究或生化研究中，需关注其存在可能带来的影响。

干品多肽的重量中不仅仅包含多肽，还包含有一些非肽的组份，如水、被吸收的溶剂、配位离子和盐等。肽的净含量是指肽在其中的重量百分比，这个百分比的数值范围很大，可能从50%到90%，取决于纯度、序列以及合成和纯化的方法，不要将肽的净含量和肽的纯度混为一谈，他们是两个完全不同的概念。纯度通常是通过HPLC测定的。纯度定义的是多肽样品中含正确序列的组分的百分比，而肽的净含量是指样品中肽类物质相对于总物质所占的百分比，肽的净含量通常是氨基酸组分分析或紫外分光法测定的，这个信息主要是在一些对肽的浓度很敏感的实验中，对计算肽的浓度是很重要的。