Stromal cells are a diverse group of connective tissue cells found in various organs and tissues throughout the body. Unlike parenchymal cells, which carry out the primary functions of an organ, stromal cells provide structural support and create a microenvironment essential for tissue maintenance, repair, and immune regulation. They include fibroblasts, pericytes, adipocytes, endothelial cells, and mesenchymal stromal/stem cells (MSCs).
One of the key roles of stromal cells is in the bone marrow, where they support hematopoietic stem cells (HSCs) by secreting cytokines and growth factors that regulate blood cell production. Stromal cells also play a significant role in the extracellular matrix (ECM) by producing collagen, fibronectin, and other proteins that influence cell behavior and tissue architecture.
In recent years, stromal cells—especially MSCs—have garnered attention in regenerative medicine due to their ability to differentiate into bone, cartilage, and fat cells, and for their immunomodulatory properties. MSCs can reduce inflammation and promote healing in damaged tissues, making them a potential therapy for conditions like osteoarthritis, Crohn’s disease, and graft-versus-host disease.
Additionally, stromal cells contribute to the tumor microenvironment. Cancer-associated fibroblasts (CAFs), a type of stromal cell, can either suppress or promote tumor growth depending on context, highlighting the complexity of stromal cell interactions.
Overall, stromal cells are essential for maintaining tissue health and function, and ongoing research continues to explore their therapeutic potential in a wide range of diseases and injuries.
