Journal: Infection and Immunity

Article Title: Zinc-limited Mycobacterium tuberculosis stimulate distinct responses in macrophages compared with standard zinc-replete bacteria

doi: 10.1128/iai.00578-24

Figure Lengend Snippet: Macrophages more readily phagocytose Zn 2+ -limited Mtb than Zn 2+ -replete Mtb. (A) Intracellular CFUs of Aux-ZRM and Aux-ZLM in RAW 264.7 cells at 4 and 24 hpi. (B) The percentage and (C) relative bacterial burden of RAW 264.7 macrophages infected with DsRed-expressing Aux-ZRM and Aux-ZLM at 4 and 24 hpi, as determined by flow cytometry. (D) Intracellular CFUs of Rv-ZRM and Rv-ZLM in murine BMDMs at 4 hpi. (E) Intracellular CFUs of Aux-ZRM and Aux-ZLM in THP-1 macrophages at 4 hpi. (F) The percentage and (G) relative bacterial burden of THP-1 macrophages infected with GFP-expressing Aux-ZRM and Aux-ZLM at 2 hpi, as determined by flow cytometry. Bacterial burden is relative to the burden of macrophages infected with Aux-ZRM. The error bars are the standard deviations of six replicates. Representative data from at least two independent experiments are shown. **: P -value < 0.01. ***: P -value < 0.001. ****: P -value < 0.0001. CFUs: colony forming units; Aux-ZRM and Aux-ZLM: Mtb mc 2 6206 grown in Zn 2+ -replete or limited media, respectively; Rv-ZRM and Rv-ZLM: Mtb H37Rv grown in Zn 2+ -replete or limited media, respectively; BMDM: bone marrow-derived macrophages. MΦ: macrophage. a.u.: arbitrary units.

Article Snippet: The fluorescent strain of Mtb-Aux expressing DsRed (pMSP12::DsRed, Addgene plasmid # 30171) and GFP (Live-Dead reporter; a gift from Dr. Christopher Sassetti) were used for the flow cytometry assays and confocal microscopy when indicated ( , ).

Techniques: Infection, Expressing, Flow Cytometry, Derivative Assay