Researchers in this study wanted to better understand the role of the immune system in normal breast tissue. While many studies focus on immune cells within tumors, much less is known about how immune cells behave in healthy breast tissue and whether they might play a role in preventing cancer.
To investigate this, the researchers analyzed normal breast tissue samples from healthy women and measured different types of immune cells present within breast lobules (the structures that produce milk). Using specialized staining techniques, they identified and counted immune cells such as CD8+ T cells and dendritic cells, which are important for detecting and responding to abnormal cells.
The researchers found that immune cells are almost always present in normal breast tissue, even when no visible inflammation is detected. These immune cells were closely associated with the breast epithelium, suggesting they may play an active role in maintaining tissue health.
The findings suggest that the breast may have its own form of a “mucosal immune system,” similar to what exists in organs like the gut. This system may help protect against infections and could also play a role in identifying and eliminating early abnormal or cancerous cells.
