Alveolar macrophages are specialized immune cells located in the lungs, specifically within the alveoli, which are tiny air sacs responsible for gas exchange. Their primary role is to protect the respiratory system by engulfing and digesting pathogens, debris, and other foreign particles that enter the lungs. This helps maintain lung health and prevents infections. These macrophages are part of the body's innate immune system and are crucial for initiating inflammatory responses when needed. They also play a role in tissue repair and the regulation of immune responses, ensuring a balanced reaction to potential threats while minimizing damage to lung tissue.