High spatial resolution imaging of biological tissues using nanospray desorption electrospray ionization mass spectrometry (nano-DESI).

This protocol enables sensitive and quantitative imaging of lipids and metabolites in tissue sections with high throughput and spatial resolution. Hundreds of high-quality ion images were obtained from a single uterine section with a resolution of better than 10 µm.

See Yin et al.

Human blood vessel organoid

Confocal image of a blood vessel organoid derived from human pluripotent stem cells, immunostained with CD31 to visualize endothelial networks (cyan) and PDGFR-b to label pericytes (magenta).

See Wimmer et al.

Plasma cell-free DNA methylomes

Artist’s impression of cancer cells releasing cell-free DNA (cfDNA) in the bloodstream. In this issue, Shen et al. provide the cfMeDIP-seq protocol for methylome profiling of plasma cfDNA.

See Shen et al.

Clonal tracing in established colon cancer tissue using marker-independent fluorescent labelling

Schematic drawing of red fluorescent clones within established colon cancer tissue and the method to determine the maximum distance (d max) of cells within a clone, which is used to distinguish individual clones. The numbers in the circles indicate distance in cell diameters.

See Lenos et al.

Mosaic of a single Euglena gracilis cell

Mosaic of a single Euglena gracilis cell composed of numerous E. gracilis cell images acquired by the intelligent image–activated cell sorting machine.

[Correction: This text was previously published with an incorrect title, and the first line of text on the thumbnail of the cover was also incorrect; both have now been amended.]

See Isozaki et al.

A running cheetah with DeepLabCut

Image of a cheetah ‘in the wild’ with markerless tracking of user-defined parts made with DeepLabCut, an open-source toolbox for deep-learning-based animal-pose estimation provided by Nath et al.

See Nath et al.

3D confocal image of a human colon organoid.

Image of a human colon organoid immunolabeled for F-actin and E-cadherin and captured in 3D using the easy-to-use and fast protocol provided by Dekkers et al. in this issue of Nature Protocols.

See Dekkers et al.

Microfabricated blood vessels

Phase contrast (left) and immunostained micrographs (right) of perfusable human engineered microvessels used to investigate vascular barrier function. Immunostaining for VE-cadherin (white) and nuclei (magenta) demonstrates the formation of endothelial cell–cell adherens junctions that regulate the permeability of the vessel in response to flow.

See Polacheck et al.

Nanoscale diffusion dynamics using STED–FCS

Seeing nanoscale organization through a STED doughnut. Nanoscale membrane heterogeneity is investigated using a combination of super-resolution STED microscopy and fluorescence correlation spectroscopy.

See Sezgin et al.

Two-photon activation for synthetic optogenetics

Synthetic optogenetics provides a method to interrogate neuronal signaling. Depicted is a cultured hippocampal neuron (green) photostimulated by near-infrared light patterned by computer-generated holography (red and pattern).

See Carmi et al.

Systemic AAV vectors for targeted gene delivery

Multicolor labeling of cardiac muscle with systemic AAVs. Three fluorescent proteins (mTurquoise2, mNeonGreen, and mRuby2) were separately packaged into AAV-PHP.S and systemically codelivered to a wild-type mouse at 3.3 × 1011 vector genomes (vg) per virus (1 × 1012 vg total). Gene expression in the heart was evaluated 11 d later. Individual cardiomyocytes can be easily distinguished from one another.

See Challis et al.

Human gastric organoids from pluripotent stem cells

Human-pluripotent-stem-cell-derived fundic gastric organoids and antral organoids at day 20 of culture. The images show immunofluorescent staining of the organoids for the markers GATA4 (green), PDX1 (red) and CDH1/E-cadherin (white), as well as the nuclear stain DAPI (blue).

See Borda et al.