d-4f-peptide and Pneumonia

We reported that HDL loses its antiinflammatory properties during acute influenza A infection in mice, and we hypothesized that these changes might be associated with increased trafficking of macrophages into the artery wall. The present study tested this hypothesis.. D-4F, an apolipoprotein A-I mimetic peptide, or vehicle in which it was dissolved (PBS) was administered daily to LDL receptor-null mice after a Western diet and after influenza infection. D-4F treatment increased plasma HDL cholesterol and paraoxonase activity compared with PBS and inhibited increases in LDL cholesterol and peak levels of interleukin-6 after infection. Lung viral titers were reduced by 50% in mice receiving D-4F. Injection of female mice with male macrophages, which were detected with real-time polymerase chain reaction to measure the male Sry gene, revealed a marked increase in macrophage traffic into the aortic arch and innominate arteries after infection that was prevented by administration of D-4F.. We conclude that loss of antiinflammatory properties of HDL after influenza infection in mice is associated with increased arterial macrophage traffic that can be prevented by administration of D-4F.

Topics: Animals; Aorta, Thoracic; Apolipoprotein A-I; Aryldialkylphosphatase; Behavior, Animal; Body Temperature; Brachiocephalic Trunk; Cell Movement; Cells, Cultured; Diet, Atherogenic; Esterases; Female; Genes, sry; In Vitro Techniques; Interleukin-6; Lipoproteins, HDL; Lipoproteins, LDL; Macrophages, Peritoneal; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Monocytes; Orthomyxoviridae Infections; Peptides; Pneumonia; Receptors, LDL; T-Lymphocytes; Virus Replication