Surfactant protein B (SP-B, gene name: sftpb) is essential for normal lung function. It reduces alveoli surface tension, thereby preventing the lung from collapse. A single nucleotide polymorphism (SP-B 1580 C/T) is associated with several lung diseases and altered N-linked glycosylation site at Asn129 of SP-B. This change, present in the human population, has been associated with negative effects on SP-B precursor (proSP-B) processing and function. In this study, hSP-B humanized transgenic mice were generated without mouse SP-B background. Four founding lines, showing only the hSP-B gene, were selected via PCR-based DNA analysis. Genomic sequencing of these mice revealed which allele variant (hSP-B-C/T) they carried. Western blot analysis of BALF samples revealed these hTG mice expressed hSP-B protein in levels significant for survival and comparable to that of a healthy human lung. Characterization of the two hSP-B allele variant hTG strains revealed significant differences in their relative alveolar size and total lipid concentration
