In vitro interaction between Bacillus megaterium strains and Caco-2 cells Authors Ana C. López Jessica Minnaard Pablo F. Pérez Adriana L. Alippi Abstract To further our understanding of the virulence potential of Bacillus megaterium strains, cell association andinvasion assays were conducted in vitro by infecting human enterocytes (Caco-2 cells) with 53 strains of this bacteriumisolated from honey. Two series of experiments were performed: (i) necrosis and cell detachment assays with the supernatantsof bacterial culture filtrates from 16-h cultures and (ii) adhesion/invasion assays in which cultured enterocytesincubated with bacteria from 3-h cultures were resuspended in Dulbecco's modified Eagle's medium and chloramphenicol.The detachment of Caco-2 cells was evaluated by staining the cells with crystal violet. Necrosis was assessedby fluorescence microscopy of cells labeled with propidium iodide. Association (adhesion plus invasion) was determinedby plate counts and invasion in an aminoglycoside protection assay. The results showed that spent culture supernatantsdetached and necrotized Caco-2 cells in a strain-dependent manner. Seven out of 53 B. megaterium filtered culture supernatantscaused complete cell detachment. Suspensions of these same bacterial strains adhered and invaded enterocytes in2-h infection experiments. To our knowledge, this is the first report on the interaction between B. megaterium and intestinalepithelial Caco-2 cells. [Int Microbiol 2013; 16(1):27-33] Downloads PDF Issue Vol. 16 No. 1 (2013) Section Research Articles License Submission of a manuscript to International Microbiology implies: that the work described has not been published before, including publication in the World Wide Web (except in the form of an Abstract or as part of a published lecture, review, or thesis); that it is not under consideration for publication elsewhere; that all the coauthors have agreed to its publication. The corresponding author signs for and accepts responsability for releasing this material and will act on behalf of any and all coauthors regarding the editorial review and publication process.If an article is accepted for publication in International Microbiology, the authors (or other copyright holder) must transfer to the journal the right–not exclusive–to reproduce and distribute the article including reprints, translations, photographic reproductions, microform, electronic form (offline, online) or any other reproductions of similar nature. Nevertheless, all article in International Microbiology will be available on the Internet to any reader at no cost. The journal allows users to freely download, copy, print, distribute, search, and link to the full text of any article, provided the authorship and source of the published article is cited. The copyright owner's consent does not include copying for new works, or resale. In these cases, the specific written permission of International Microbiology must first be obtained.Authors are requested to create a link to the published article on the journal's website. The link must be accompanied by the following text: "The original publication is available on LINK at <http://www.im.microbios.org>. Please use the appropiate URL for the article in LINK. Articles disseminated via LINK are indexed, abstracted, and referenced by many abstracting and information services, bibliographic networks, subscription agencies, library networks, and consortia.
