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Measurement of macrophage-mediated killing of intracellular bacteria, including Francisella and mycobacteria.

Laboratory of Mycobacterial Diseases and Cellular Immunology, Division of Bacterial, Parasitic, and Allergenic Products, CBER/U.S. FDA, Rockville, Maryland, USA.
Current protocols in immunology / edited by John E. Coligan ... [et al.] 04/2011; Chapter 14:Unit14.25. DOI: 10.1002/0471142735.im1425s93
Source: PubMed

ABSTRACT Macrophages activated by T cell cytokines are a critical defense mechanism against intracellular bacterial pathogens. This unit presents two general methods for assessing the capacity of mouse macrophages, activated with either soluble cytokines or whole immune T lymphocytes, to control or reduce numbers of intracellular bacteria residing within them. "Measurement of killing" is inferred from a reduction in the number of colony-forming units (cfu) of bacteria at the end of a culture period, compared to the input numbers of cfu at initiation of culture, to the peak numbers of cfu measured during culture, or to a control group in which killing is expected to be poor.

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