TR for 30 min and uptake assessed by confocal microscopy. Quantification using ImageJ indicated no significant difference in dextran endocytosed (data not shown). Dextran treatments were performed in duplicate and repeated twice. (TIF) Acknowledgments We thank Garry Coulson for critical review of the manuscript. We also thank Shelly Helms for technical assistance in several parts of this project. References 1. Hauck FR, Neese BH, Panchal AS, El-Amin W (2009) Identification and management of latent tuberculosis infection. Am Fam Physician 79: 879–886. 2. Sato K, Tomioka H, Shimizu T, Gonda T, Ota F, et al. (2002) Type II alveolar cells play roles in macrophage-mediated host innate resistance to pulmonary mycobacterial infections by producing proinflammatory cytokines. J Infect Dis 185: 1139–1147. 3. Bermudez LE, Goodman J (1996) Mycobacterium tuberculosis invades and replicates within type II alveolar cells. Infect Immun 64: 1400–1406. 4. 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PLOS ONE | www.plosone.org 14 September 2012 | Volume 7 | Issue 9 | e45028