Kaposiform lymphangiomatosis (KLA) is a vascular anomaly featuring lymphatic expansion. It has no known cause, no effective treatment, and is associated with high morbidity. Proliferative cells from 3 KLA patient lesions were characterized relative to adiopose-derived mesenchyme stem cells (ADSCs) and cells derived from a patient with the related disease kaposiform hemangioendothelioma (KHE). KLA cells variably expressed markers of mesenchyme stem cells (CD73, CD90, CD105, CD146) and lacked endothelial cell markers (CD31, CD34) as determined by flow cytometry. They expressed markers of vascular pericytes (neural/glial antigen 2, alpha-smooth muscle actin, platelet-derived growth factor-beta receptor, and CXCL12) as determined by quantitative reverse transcription polymerase chain reaction. Lesion cells transcribed vascular markers VEGFC and VEGFD, as well as VCAM-1, the latter of which was confirmed by flow cytometry, consistent with angiogenic MSC-like pericytes. Furthermore, conditioned medium from each was shown to promote the proliferation of growth factor–starved lymphatic endothelial cells. Unlike kaposiform hemangioendothelioma-derived MSC-like pericytes and ADSCs, KLA isolates were defective in support of vascular network formation in co-cultures with either vascular or lymphatic endothelial cells. Genetic analysis by whole exome sequencing revealed novel variant alleles in 2 populations of KLA cells (BAD, TSC1) that may bear on aberrant pericyte growth and function.
*Department of Pediatric Surgery, Cincinnati Children’s Hospital and Medical Center, Cincinnati, OH
†Department of Surgery, Boston Children’s Hospital, Boston, MA
All flow cytometric data were acquired using equipment maintained by the Research Flow Cytometry Core in the Division of Rheumatology at Cincinnati Children’s Hospital Medical Center, supported in part by NIH AR-47363, NIH DK78392, and NIH DK90971. This work was initiated and completed at the Cincinnati Children’s Hospital and Medical Center, with the financial support of the Department of Pediatric General and Thoracic Surgery.
The authors declare no conflict of interest.
Reprints: Belinda Hsi Dickie, MD, PhD, 300 Longwood Avenue, Fegan 3, Boston Children’s Hospital, Boston, MA 02115 (e-mail: email@example.com).
Received November 5, 2017
Accepted July 5, 2018