"Modification of Figure 1C. in Greenland, J.R., Xu, X., Sayah, D.M. et al. Mast cells in a murine lung ischemia-reperfusion model of primary graft dysfunction. Respir Res 15, 95 (2014). https://doi.org/10.1186/s12931-014-0095-0 CC BY 4.0. Figure 1.12: Natural killer (NK) cells are inhibited by the presence of the major histocompatibility cell (MHC) receptor on healthy cells. (c) Rice University. OpenStax Microbiology. CC BY 4.0. https://openstax.org/details/books/microbiology. Figure 1.13: Natural killer cell with perforin-containing granules. Modification of Figure 1 in Rolstad B (2014) The early days of NK cells: an example of how a phenomenon led to detection of a novel immune receptor system – lessons from a rat model. Front. Immunol. 5:283. https://doi.org/10.3389/fimmu.2014.00283 CC BY 4.0. Figure 1.14: Monocytes are large, agranular white blood cells with a nucleus that lacks lobes. Left: Modification of work by Armed Forces Institute of Pathology. Public Domain. https://commons.wikimedia.org/wiki/File:AML-M4.jpg. Right: Modification of work by Centers for Disease Control and Prevention/Martin D. Hicklin. Public Domain. https://phil.cdc.gov/Details.aspx?pid=6625. Figure 1.15: Damaged cells and macrophages that have ingested pathogens release cytokines that are proinflammatory and chemotactic for leukocytes. (c) Rice University. OpenStax Microbiology. CC BY 4.0. https://openstax.org/details/books/microbiology. Figure 1.16: Phagocytic cells contain pattern recognition receptors (PRRs) capable of recognizing various pathogen-associated molecular patterns (PAMPs). (c) Rice University. OpenStax Microbiology. CC BY 4.0. https://openstax.org/details/books/microbiology. Figure 1.17: The stages of phagocytosis include the engulfment of a pathogen, the formation of a phagosome, the digestion of the pathogenic particle in the phagolysosome, and the expulsion of undigested materials from the cell. (c) Rice University. OpenStax Microbiology. CC BY 4.0. https://openstax.org/details/books/microbiology. Figure 1.18: Mast cells detect injury to nearby cells and release histamine, initiating an inflammatory response. (c) Rice University. OpenStax Microbiology. CC BY 4.0. https://openstax.org/details/books/microbiology. Figure 1.19: A tubercle is a granuloma in the lung tissue of a patient with tuberculosis. Modified figure by 1C in (c) Piotrowski WJ, Górski P, Duda-Szymańska J, Kwiatkowska S. Mycobacterium tuberculosis as a sarcoid factor? A case report of family sarcoidosis. Am J Case Rep. 2014 May 16;15:216-20. CC BY-NC-ND 3.0 Unported. https://pmc.ncbi.nlm.nih.gov/articles/PMC4026149. Reproduced under Fair Use. Figure 1.20: The role of the hypothalamus in the inflammatory response. Left: Public Domain. https://commons.wikimedia.org/wiki/File:Hypothalamus.jpg. Right: (c) Rice University. OpenStax Microbiology. CC BY 4.0. https://openstax.org/details/books/microbiology."