12 research outputs found
Etablierung und Evaluierung von Markierungsstrategien zur nichtinvasiven in vivo Darstellung der Migration von murinen CD4 + -T-Helfer-Zellen
In-vivo imaging of tumor-infiltrating immune cells: implications for cancer immunotherapy
Tracking the fate of adoptively transferred myeloid-derived suppressor cells in the primary breast tumor microenvironment
Comparison of the Accuracy of FMT/CT and PET/MRI for the Assessment of Antibody Biodistribution in Squamous Cell Carcinoma Xenografts
Positron Emission Tomography/Computed Tomographic and Magnetic Resonance Imaging in a Murine Model of Progressive Atherosclerosis Using Cu-64-Labeled Glycoprotein VI-Fc
In vivo Optical Imaging of Matrix Metalloproteinase Activity Detects Acute and Chronic Contact Hypersensitivity Reactions and Enables Monitoring of the Antiinflammatory Effects of -Acetylcysteine
The aim of this study was to determine whether the severity of contact hypersensitivity reactions (CHSRs) can be observed by noninvasive in vivo optical imaging of matrix metalloproteinase (MMP) activity and whether this is an appropriate tool for monitoring an antiinflammatory effect. Acute and chronic CHSRs were elicited by application of a 1% trinitrochlorobenzene (TNCB) solution for up to five times on the right ear of TNCB-sensitized mice. N -Acetylcysteine (NAC)-treated and sham-treated mice were monitored by measuring ear swelling and optical imaging of MMP activity. In addition, we performed hematoxylin-eosin staining and CD31 immunohistochemistry for histopathologic analysis of the antiinflammatory effects of NAC. The ear thickness and the MMP activity increased in line with the increasing severity of the CHSR. MMP activity was enhanced 2.5- to 2.7-fold during acute CHSR and 3.1- to 4.1-fold during chronic CHSR. NAC suppressed ear swelling and MMP signal intensity in mice with acute and chronic CHSR. During chronic CHSR, the vessel density was significantly reduced in ear sections derived from NAC-treated compared to sham-treated mice. In vivo optical imaging of MMP activity measures acute and chronic CHSR and is useful to monitor antiinflammatory effects
Visualization and quantification of in vivo homing kinetics of myeloid-derived suppressor cells in primary and metastatic cancer
Cu-64 antibody-targeting of the T-cell receptor and subsequent internalization enables in vivo tracking of lymphocytes by PET
T cells are key players in inflammation, autoimmune diseases, and immunotherapy. Thus, holistic and noninvasive in vivo characterizations of the temporal distribution and homing dynamics of lymphocytes in mammals are of special interest. Herein, we show that PET-based T-cell labeling facilitates quantitative, highly sensitive, and holistic monitoring of T-cell homing patterns in vivo. We developed a new T-cell receptor (TCR)-specific labeling approach for the intracellular labeling of mouse T cells. We found that continuous TCR plasma membrane turnover and the endocytosis of the specific (64)Cu-monoclonal antibody (mAb)–TCR complex enables a stable labeling of T cells. The TCR–mAb complex was internalized within 24 h, whereas antigen recognition was not impaired. Harmful effects of the label on the viability, DNA-damage and apoptosis-necrosis induction, could be minimized while yielding a high contrast in in vivo PET images. We were able to follow and quantify the specific homing of systemically applied (64)Cu-labeled chicken ovalbumin (cOVA)-TCR transgenic T cells into the pulmonary and perithymic lymph nodes (LNs) of mice with cOVA-induced airway delayed-type hypersensitivity reaction (DTHR) but not into pulmonary and perithymic LNs of naïve control mice or mice diseased from turkey or pheasant OVA-induced DTHR. Our protocol provides consequent advancements in the detection of small accumulations of immune cells in single LNs and specific homing to the sites of inflammation by PET using the internalization of TCR-specific mAbs as a specific label of T cells. Thus, our labeling approach is applicable to other cells with constant membrane receptor turnover