single-cell RNA sequencing analysis of metaphocytes and epidermal cells
Metaphocytes are tissue-resident myeloid-like cells of non-hematopoietic origin in zebrafish barrier tissues. How metaphocytes acquire myeloid cell properties from non-hematopoietic precursors during the development remains unknown. Here we show that metaphocytes are in situ generated from local progenitors guided by the ETS transcription factor Spic. Tg(spic:EGFP) transgenic fish were found to label both metaphocytes and their progenitor cells. To reveal the genetic programs underlying the development of metaphocytes, we performed single-cell RNA sequencing analysis of spic:GFP+ cells in the  epidermis of adult Tg(spic:EGFP) fish. The result further supports that mature metaphocytes are generated from spic+ progenitors via an intermediate immature state and gradually obtain their myeloid characteristics during this process. Overall design: scRNA-seq (10X genomics 3' V3.1) analysis of FACS-sorted spic:EGFP+ and singlet cells  from the epidemris of 6-month-old Tg(spic:EGFP) fish