Pericytes are heterogeneous in their origin within the same tissue

Abstract

Pericytes heterogeneity is based on their morphology, distribution, and markers. It is well known that pericytes from different organs may have distinct embryonic sources. Yamazaki et al. (2017) using several transgenic mouse model reveal by cell-lineage tracing that pericytes are even more heterogeneous than previously appreciated. This study shows that pericytes from within the same tissue may be heterogeneous in their origin. Remarkably, a subpopulation of embryonic dermal pericytes derives from the hematopoietic lineage, an unexpected source. Reconstructing the lineage of pericytes is central to understanding development, and also for the diagnosis and treatment of diseases in which pericytes play important roles.

Keywords: Embryonic; Origin; Pericytes; Plasticity; Stem cells.

Figure 1. Heterogeneity in the pericytes origins

Pericytes are present around blood vessels in several tissues, such as brain, heart, lungs, skeletal muscle, pancreas, intestine, bone marrow, kidney, and others. During the embryonic development, pericytes in the head, cephalic region and thymus originate from the neuroectodermis, the ones found in gut, liver, lungs and heart are derived from the mesothelium, while the mesoderm gives rise to pericytes in other organs (such as kidneys, liver and pancreas). The study of Yamazaki and colleagues now suggests that surprisingly a subgroup of pericytes may derive from the hematopoietic lineage (Yamazaki et al., 2017). With the appearance of state of art technologies, such as new pericyte-lineage tracing mouse models, the true origin of pericytes subgroups will likely be revealed with much greater details in future studies.