| Autor: |
Oberley, Rebecca E., Snyder, Jeanne M. |
| Předmět: |
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| Zdroj: |
American Journal of Physiology: Lung Cellular & Molecular Physiology; May2003, Vol. 28 Issue 5, pL871, 11p, 14 Diagrams, 14 Graphs |
| Abstrakt: |
Surfactant protein (SP)-A is a member of the collectin family of proteins and plays a role in innate host defense of the lung. SP-A binds to the carbohydrates of lung pathogens via its calcium-dependant carbohydrate-binding domain. Native human alveolar SP-A consists of two distinct gene products: SP-A1 and SP-A2; however, only SP-A2 is expressed in the submucosal glands of the conducting airways. The function of the isolated SP-A2 protein is unknown. We hypothesized that SP-A1 and SP-A2 might have different carbohydrate-binding properties. In this study, we characterized the carbohydratebinding specificities of native human alveolar SP-A and recombinant human SP-A1 and SP-A2 in the presence of either 1 or 5 mM Ca[sup 2+]. We found that all of the SP-A proteins bind carbohydrates but with different affinities. All of the SP-A proteins bind to fucose with the greatest affinity. SP-A2 binds with a higher affinity to a wider variety of sugars than SP-A1 at either 1 or 5 mM Ca[sup 2+]. These findings are suggestive that SP-A2 may interact with a greater variety of pathogens than native SP-A. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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