Hermansky-Pudlak Syndrome: From Molecular Pathogenesis to Targeted Therapies

Abstract

Hermansky-Pudlak syndrome (HPS) is a rare inherited disorder caused by defects in lysosome-related organelles (LROs) in various tissues, including platelets, melanocytes, and endothelial cells. Key features of HPS include oculocutaneous albinism, bleeding tendency, and, in some cases, pulmonary fibrosis, granulomatous colitis, and immunodeficiency. The condition is linked to mutations in 11 genes involved in the formation of LROs. Currently, treatment options for HPS are limited and often ineffective. Though cell and gene therapies have been explored for melanosomes and epithelial cells, there is limited knowledge about their application to platelets and endothelial cells. Understanding the detailed mechanisms of HPS pathogenesis is crucial, and using induced pluripotent stem cell (iPSC) models may provide valuable insights into the disease's molecular processes, aiding the development of new treatments. In this review, we will focus on the genetics and molecular mechanisms of HPS, on its clinical manifestations and current therapeutic approaches, highlighting the need for further research into the disease mechanisms and potential innovative therapies.

FIGURE 1

Representation of BLOC complexes involved in HPS, with their subunits and their role in the biogenesis of LROs. Created in BioRender. https://BioRender.com/k31r516.

FIGURE 2

Most common clinical manifestation in HPS subtypes with associated defective LROs and cell type. Created in BioRender. https://BioRender.com/p55c817.