SFTPA1, or Surfactant Protein A1, is a protein that plays a crucial role in the immune system, particularly in the lungs. It is part of a group of proteins known as surfactant proteins, which help reduce surface tension in the alveoli, the tiny air sacs in the lungs. This function is essential for proper lung function and helps prevent respiratory infections. Additionally, SFTPA1 is involved in the body's response to pathogens. It can bind to various microorganisms, aiding in their recognition and clearance by immune cells. This makes SFTPA1 important for maintaining lung health and overall immune defense against respiratory diseases.