TY  - JOUR
A1  - Nerreter, Thomas
A1  - Letschert, Sebastian
A1  - Götz, Ralph
A1  - Doose, Sören
A1  - Danhof, Sophia
A1  - Einsele, Hermann
A1  - Sauer, Markus
A1  - Hudecek, Michael
T1  - Super-resolution microscopy reveals ultra-low CD19 expression on myeloma cells that triggers elimination by CD19 CAR-T
JF  - Nature Communications
N2  - Immunotherapy with chimeric antigen receptor-engineered T-cells (CAR-T) is under investigation in multiple myeloma. There are reports of myeloma remission after CD19 CAR-T therapy, although CD19 is hardly detectable on myeloma cells by flow cytometry (FC). We apply single molecule-sensitive direct stochastic optical reconstruction microscopy (dSTORM), and demonstrate CD19 expression on a fraction of myeloma cells (10.3–80%) in 10 out of 14 patients (density: 13–5,000 molecules per cell). In contrast, FC detects CD19 in only 2 of these 10 patients, on a smaller fraction of cells. Treatment with CD19 CAR-T in vitro results in elimination of CD19-positive myeloma cells, including those with <100 CD19 molecules per cell. Similar data are obtained by dSTORM analyses of CD20 expression on myeloma cells and CD20 CAR-T. These data establish a sensitivity threshold for CAR-T and illustrate how super-resolution microscopy can guide patient selection in immunotherapy to exploit ultra-low density antigens.
KW  - cancer imaging
KW  - cancer immunotherapy
KW  - imaging
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232258
VL  - 10
ER  - 
TY  - JOUR
A1  - Kunz, Tobias C.
A1  - Götz, Ralph
A1  - Sauer, Markus
A1  - Rudel, Thomas
T1  - Detection of chlamydia developmental forms and secreted effectors by expansion microscopy
JF  - Frontiers in Cellular and Infection Microbiology
N2  - Expansion microscopy (ExM) is a novel tool to improve the resolution of fluorescence-based microscopy that has not yet been used to visualize intracellular pathogens. Here we show the expansion of the intracellular pathogen Chlamydia trachomatis, enabling to differentiate its two distinct forms, catabolic active reticulate bodies (RB) and infectious elementary bodies (EB), on a conventional confocal microscope. We show that ExM enables the possibility to precisely locate chlamydial effector proteins, such as CPAF or Cdu1, within and outside of the chlamydial inclusion. Thus, we claim that ExM offers the possibility to address a broad range of questions and may be useful for further research on various intracellular pathogens.
KW  - expansion microscopy
KW  - chlamydia
KW  - secreted effectors
KW  - developmental forms
KW  - superresolution
KW  - imaging
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-195716
SN  - 2235-2988
VL  - 9
IS  - 276
ER  -