HIGD1B (HIG1 hypoxia inducible domain family member 1B) serves as a specific marker for pericytes, the mural cells that wrap around capillaries and regulate vascular homeostasis 12. The protein functions in mitochondrial respirasome assembly and is localized to mitochondria, playing a critical role in cellular energy metabolism 3. HIGD1B expression identifies distinct pericyte subtypes in pulmonary capillaries, where it helps distinguish pericytes from other stromal cells and enables study of their specialized functions 24. In disease contexts, HIGD1B downregulation is associated with chr17 obstructive pulmonary disease (COPD), correlating with mitochondrial dysfunction and altered immune cell infiltration 3. In gastric cancer, elevated HIGD1B levels predict poor prognosis and function as an oncogene, with its downregulation inducing mitochondria-mediated apoptosis through inactivation of Akt and ERK pathways 5. The gene also shows organ-specific expression patterns, being particularly enriched in lung and heart pericytes, and its expression is conserved between mouse and human tissues 1. HIGD1B represents a valuable biomarker for pericyte identification and a potential therapeutic target in vascular diseases and cancer.