Fig. 4
From: Engineered live bacteria as disease detection and diagnosis tools
Bacteria as imaging vectors. A Super-imposed PET and CT images of established infection 2 h post [124I]FIAU radiotracer administration in human patients. (i) methicillin-resistant Staphylococcus aureus (MRSA)-caused septic arthritis (right knee with a prosthetic joint), (ii) MRSA-induced septic arthritis (right knee with history of chronic MRSA osteomyelitis), (iii) cellulitis (left lower extremity with history of osteomyelitis in the left distal tibia), (iv) necrotizing MRSA osteomyelitis of the proximal tibia (left knee). Reprinted with permission from [130]. B In situ bARGSer expression by E. coli Nissle 1917 (EcN) for ultrasound imaging of tumor colonization. Representative parabolic ultrasound (pAM) and Burst Ultrasound Reconstructed with Signal Templates (BURST) images of tumors colonized by bARGSer-expressing EcN (i) at 1 day after induction with intraperitoneally injected L-arabinose (on day 18 post subcutaneous injection of tumor cells and day 4 post tail vein injection of EcN bacteria), (ii) at 1 day after the collapse of gas vesicles and re-injection of L-arabinose for re-induction (day 19), (iii) uninduced on day 18, (iv) pAM and BURST images of tumors colonized by fluorescence protein-expressing (FP) EcN after L-arabinose induction. Reprinted with permission from [135]. C R2 relaxation maps of mammary tumors obtained before and after L-arabinose induction of bacterioferritin (bfr) expression. Tumor-bearing mice were injected with control bacteria (upper panel) or PBAD-bfr encoding EcN (lower panel). Left and right panels are before and 24 h after injection of L-arabinose, respectively.. Reprinted with permission from [137]. D In vivo bioluminescence imaging of S. Typhimurium ΔppGpp tropism for myocardial infarction. Time course study of bioluminescence after intravenous injection of bacteria in mice with or without myocardial infarction. Reprinted with permission [153]. E Photoacoustic imaging-guided synergistic photothermal therapy. (i) Illustration of the preparation of ternary photosensitive bacteria by combining genetic engineering for melanin expression with surface co-deposition of polydopamine and synthetic indocyanine green (ICG). (ii) Monochromatic irradiation at 808 nm results in stable triple photoacoustic and photothermal effects for imaging and therapy. Reprinted with permission from [154]. F Acute spinal implant infection excision under the fluorescence image-guided surgery system. Analysis of images without (i-iii) and with (iv-vi) fluorescence excitation at 680 shows no fluorescence signal prior to skin incision (i) and (iv); the presence of strong fluorescence signal with excitation post skin incision (v), and reminiscent fluorescence signal post partial excision of infected tissue (vi). Reproduced with permission [167]