title: Bacterial Infection and Immune Responses in Lutzomyia longipalpis Sand Fly Larvae Midgut.
abstract: The midgut microbial community in insect vectors of disease is crucial for an effective immune response against infection with various human and animal pathogens. Depending on the aspects of their development, insects can acquire microbes present in soil, water, and plants. Sand flies are major vectors of leishmaniasis, and shown to harbor a wide variety of Gram-negative and Gram-positive bacteria. Sand fly larval stages acquire microorganisms from the soil, and the abundance and distribution of these microorganisms may vary depending on the sand fly species or the breeding site. Here, we assess the distribution of two bacteria commonly found within the gut of sand flies, Pantoea agglomerans and Bacillus subtilis. We demonstrate that these bacteria are able to differentially infect the larval digestive tract, and regulate the immune response in sand fly larvae. Moreover, bacterial distribution, and likely the ability to colonize the gut, is driven, at least in part, by a gradient of pH present in the gut.
authors.affiliation: Department of Entomology, Kansas State University, Manhattan, Kansas, United States of America.
authors.forename: Matthew
authors.initials: M
authors.lastname: Heerman
authors.affiliation: Department of Entomology, Kansas State University, Manhattan, Kansas, United States of America.
authors.forename: Ju-Lin
authors.initials: JL
authors.lastname: Weng
authors.affiliation: Department of Internal Medicine, University of New Mexico School of Medicine Albuquerque, New Mexico, United States of America.
authors.forename: Ivy
authors.initials: I
authors.lastname: Hurwitz
authors.affiliation: Department of Internal Medicine, University of New Mexico School of Medicine Albuquerque, New Mexico, United States of America; New Mexico VA Health Care System, Albuquerque, New Mexico, United States of America.
authors.forename: Ravi
authors.initials: R
authors.lastname: Durvasula
authors.affiliation: Department of Entomology, Kansas State University, Manhattan, Kansas, United States of America.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Ramalho-Ortigao
mesh_terms: D000818:Animals; D001412:Bacillus subtilis / Q000235:genetics / Q000502:physiology*; D001424:Bacterial Infections / Q000382:microbiology / Q000635:transmission; D005260:Female; D041981:Gastrointestinal Tract / Q000276:immunology / Q000382:microbiology; D006801:Humans; D007303:Insect Vectors / Q000276:immunology* / Q000382:microbiology; D007814:Larva / Q000254:growth & development / Q000276:immunology / Q000382:microbiology*; D008297:Male; D020636:Pantoea / Q000235:genetics / Q000502:physiology*; D011576:Psychodidae / Q000254:growth & development / Q000276:immunology* / Q000382:microbiology