隨著單細胞數(shù)據(jù)的不斷積累和轉(zhuǎn)化樟插，拿一個組織畫個圖譜的草莽時代已經(jīng)基本一去不復(fù)返了。往深了做的一個方面就是做某個細胞類型的圖譜鸭津。特別是對那些異質(zhì)性較高的細胞類型套啤。
例如宽气，我們熟悉的fibroblast 就是這樣的一類細胞，先來看看科普級的介紹：
https://www.britannica.com/science/fibroblast
成纖維細胞，結(jié)締組織的主要活性細胞抹竹。成纖維細胞是大的线罕、扁平的止潮、細長的(紡錘形)細胞窃判，具有從細胞體末端延伸出來的突起。細胞核呈扁平橢圓形喇闸。成纖維細胞產(chǎn)生膠原蛋白的前身膠原蛋白和基質(zhì)袄琳，基質(zhì)是一種無定形凝膠狀基質(zhì)，填充在結(jié)締組織的細胞和纖維之間燃乍。
成纖維細胞似乎在傷口愈合中起著重要的作用唆樊，而這種活性被認為是由位于組織基質(zhì)中的纖維細胞調(diào)節(jié)的。在組織損傷后刻蟹，成纖維細胞遷移到損傷部位逗旁，在那里沉積新的膠原蛋白，促進愈合過程探赫。
纖維細胞是指細胞處于不活躍狀態(tài)随抠，參與組織的維護和代謝蕉饼。一些研究人員用成纖維細胞來表示這兩種細胞狀態(tài)，但“blast”一詞通常指干細胞或細胞的激活狀態(tài)淀衣。
成纖維細胞最初來源于原始間充質(zhì)，因此顯示出絲蛋白波形蛋白召调，作為中胚層起源的標記膨桥。在某些情況下，上皮細胞也可以產(chǎn)生成纖維細胞唠叛，這個過程被稱為上皮-間充質(zhì)轉(zhuǎn)化(EMT)只嚣。相反，成纖維細胞有時會發(fā)生間充質(zhì)-上皮轉(zhuǎn)變(MET)產(chǎn)生上皮細胞艺沼，這一過程見于發(fā)育介牙、組織修復(fù)和腫瘤生長。
https://www.news-medical.net/health/What-are-Fibroblasts.aspx
下面我們走馬觀花似的澳厢，看幾篇案例环础。
這就，能寫一段剩拢，就是寫哪個marker在哪些cluster里表達了线得，好處是，我們可以從這里面copy marker list：
Cancer-associated fibroblasts (CAFs) are a prominent stromal cell type in solid tumors and molecules secreted by CAFs play an important role in tumor progression and metastasis.
Feature plots showing the expression of CAF markers Acta2, Ly6c1, Cdk1, Cd74, Crabp1and Cd53intheCAF clusters identified with 1000 most variable genes徐伐。
Cells in cluster 4 had high levels of Thy1, Pdpn and Pdgfra [25] and were identified as CAFs贯钩。
Fibroblast Activation Protein (FAP) marker
monocle2 用的可以啊，中規(guī)中矩的一篇文章，分群角雷，差異祸穷，go
、kegg富集勺三。
- Distinct MC subtypes were defined by single-cell transcriptome analysis
- Lipofibroblasts were identified
- Fibrotic Pdgfrb high MC subtype emerges post-injury
- Integrative analysis of MC trajectories was constructed by machine learning
We found that these Adrp and Pparg highly expressing MCs were clustered together to form a distinct subpopulation, and at the same time, this cluster also expresses considerable levels of Fabp1,4,5, Lpl, and Lipa. Therefore, we referred to this cluster as lipofibroblasts雷滚。
It is interesting that M2 macrophage-like signature genes , together with mesenchymal genes (Mlc1, Plek, CD44, Ptpn12, and Slpi), are expressed in the lipofibroblast subtype
Seven clusters comprised the two key cell types of the skin, keratinocytes and fibroblasts. Keratinocytes were detected in three clusters (#5, #7 and #15) and their diversity was mainly due to their degree of differentiation. While epidermal stem cells (EpSC) and other undifferentiated progenitors (#7 and #15) expressed markers such as KRT5, KRT14, TP63, ITGA6, and ITGB1, differentiated keratinocytes (#5) were defined by KRT1, KRT10, SBSN, and KRTDAP expression33 (Fig. 1c and Supplementary Fig. 1c). Fibroblasts were identified by their archetypal markers LUM, DCN, VIM, PDGFRA, and COL1A227, constituted the most abundant skin cell type (5948 cells in total), and were represented by four clusters (#1, #2, #3, and #9, Fig. 1c and Supplementary Fig. 1c). Despite the lower amount of cells, the individual analysis of each sample generated a similar number of clusters and identified the same major cell types (Supplementary Fig. 2).
