Theisen, Erin2011-05-122011-05-122011-04-13https://hdl.handle.net/11299/104432Additional contributor: Caroline George (faculty mentor)Surfactant protein-A (SP-A) plays a critical role in the innate immune system and has well characterized effects in the lung where it attenuates inflammatory responses and controls invasion of bacteria. Extra-pulmonary sources of SP-A have also been indentified : SP-A mRNA has been detected in the murine neonatal and adult gastrointestinal (GI) tract, while significant levels of SP-A protein have been detected in amniotic fluid. A novel finding by the George research lab showed that SP-A knockout (-/-) newborn mice raised in a bacterial laden corn dust environment exhibited intestinal inflammation-- instead of pulmonary inflammation--and higher rates of death. Further studies have shown that SP-A -/- mice exhibit abnormal bacterial colonization patterns in the GI tract compared to their wild-type counterparts, indicating a role for SP-A in the newborn intestinal tract. To date it is not clear if newborn intestinal exposure to SP-A comes from ingested amniotic fluid or from production in the newborn intestinal tract. RT-qPCR showed low levels of SP-A gene expression in the newborn murine GI tract; yet, we and others have had mixed results regarding the detection of SP-A protein via immunohistochemistry. To address the question of intestinal exposure of SP-A in the newborn, I will perform RNA in situ hybridization to identify gene expression in specific cells of the GI tract. I have designed a 438 bp digoxigenin-labeled antisense RNA probe specific for the SP-A gene. This probe will be used on flash-frozen GI and lung tissue sections of mice at post-natal days of life 5 and 6 with an in situ hybridization protocol designed by the Panoskaltsis-Mortari laboratory.en-USCollege of Biological SciencesGenetics, Cell Biology and DevelopmentMedical SchoolDepartment of PediatricsCollege of Liberal ArtsPresentation