What are "lepra" cells?

Lepra cells are specifically identified as macrophages that contain acid-fast bacilli, which are the bacteria responsible for leprosy, known scientifically as Mycobacterium leprae. This bacterium is a slow-growing organism that primarily affects the skin, peripheral nerves, and mucous membranes. The presence of these bacilli within the macrophages indicates an ongoing infection and plays a critical role in the pathology of leprosy.

In leprosy, the immune response involves the recruitment of macrophages to the site of infection. However, M. leprae can survive and multiply within these immune cells, leading to a characteristic cellular appearance. These infected macrophages are what are referred to as lepra cells. Their identification is significant in diagnosing and understanding the disease process and pathology of leprosy.

Other options, such as healthy macrophages, do not represent the infected state associated with leprosy, while damaged nerve cells and fat cells in the skin do not relate to the characteristic presence of M. leprae in immune cells.