In addition, surfactant deficiency will impair opsonization
and phagocytosis of bacteria by macrophages, thus favoring
bacterial multiplication and leukocyte infiltration. Due to a
lack of the opsonizing effect (due to decreased concentration
of secretory IgA and surfactant deficiency), the leukocytes
cannot phagocytose and destroy the bacteriawith continuous
production of proteolytic enzymes in the secretion, which are
probably harmful to the mucous membrane, as it is known
that inhalation of proteolytic enzymes produces emphysema
in animals. Our results support the previously reported
concept that SP has an important function in immunologic
process of the nasal mucosa.7