Magnesium facilitates the healing of atypical femoral fractures: A single-cell transcriptomic study

We reported the application of single-cell mRNA sequencing to identify a unique population of fibroblasts that exits in the fracture callus of bisphosphonate-treated rats. Such unique population of fibroblasts prevented fracture healing by secreting ECM. Further, it was found that these ECM-secreting fibroblasts were enriched for myeloid genes, suggesting a bone marrow orgin. After fractures were treated with local CGRP injection or Magnesium based biometal, such population of fibroblasts was cleared off, resulting in facilitated fracture healing of bisphosphonate-treated rats. Overall design: Eight batches of single cell libraries for sequencing: control rats on week 4, control rats on week 12, bisphosphonate-treated rats on week 4, bisphosphoante-treated rats on week 12, CGRP treated rats on week 4, CGRP treated rats on week 12, Mg treated rats on week 4, Mg treated rats on week 12. Library was prepared by using 10,000 cell for group by Chromium controller (V3 chemistry version, 10X Genomics Inc, San Francisco, USA), barcoded and purified as described by the manufacturer, and sequenced using a 2x150 pair-end configuration on an Illumina HiSeq platform at a sequencing depth of ~400 million reads.