Pulmonary surfactant is a surface-active lipoprotein complex (phospholipoprotein) formed by type II alveolar cells. The proteins and lipids that make up the surfactant have both hydrophilic and hydrophobic regions.
Antibody deficiencies, also called immunoglobulin deficiency syndromes, are immune system disorders that are characterized by low or absent levels of immunoglobulin in the blood.Immunoglobulins (Ig) are antibodies that play an essential role in the body's immune system.he antibodies are present in the bloodstream or bound to the outer surfaces of B-cells or plasma cells. There are five classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM. Patients who have antibody deficiencies may have reduced or absent levels of one or more types of immunoglobulin.
IgA Deficiency and Diseases. The most prevalent antibody defect is a selective IgA deficiency (SIgAD). Alterations in IgA1/IgA2 ratio very often go hand in hand with specific disease states such as recurring infections of the airways or a kidney disorder called IgA nephropathy.