Contact & Support
Header Image

Christoph Greb, Dr.

Greb_09.jpg

Christoph Greb studied cell biology, parasitology and virology at the Philipps University in Marburg. In the course of his diploma thesis and his dissertation at the local Institute for Cytobiology and Cytopathology he examined the vesicular transport of apically destined proteins in polarized epithelial cells utilizing biochemistry as well as TIRF and confocal microscopy. From December 2011 he was writing for the Leica Science Lab as a freelancer. After his engagement for Novartis Vaccines & Diagnostics he started as Scientific Writer for the widefield team of Leica Microsystems in October 2013.

 

 

  • Introduction to Mammalian Cell Culture

    Mammalian cell culture is one of the basic pillars of life sciences. Without the ability to grow cells in the lab, the fast progress in disciplines like cell biology, immunology, or cancer research would be unthinkable. This article gives an overview of mammalian cell culture systems. Mainly, they can be categorized according to their morphology, as well as cell type and organization. Moreover, you can find basic information about the correct growth conditions and what kind of microscope you need to watch your cells.
    Read article
  • What is Photomanipulation?

    The term photomanipulation describes a wide range of techniques that enable the microscopist the transition from passive observer to instigator of events by offering a way of interacting with their sample via targeted illumination. Typically researchers are trying to observe specific processes of interest in order to understand the underlying biological process. Microscopists are often forced to hunt through large populations of cells or acquire hours of time laps footage before they’re able to observe events of interest and in many cases it’s simply not possible to observe certain processes using conventional microscopy techniques alone. Photomanipulation tools enable the microscopist to initiate biological events, precisely adjusting sample labeling, biological activity, local chemical environments and in some instances physically destroy parts of their specimen.
    Read article
  • Photoactivatable, photoconvertible, and photoswitchable Fluorescent Proteins

    Fluorescent proteins (FPs) such as GFP, YFP or DsRed are powerful tools to visualize cellular components in living cells. Nevertheless, there are circumstances when classical FPs reach their limits. Watching dedicated, spatially limited protein populations of a certain protein of interest is impossible with common FPs, since they are expressed throughout the entire cell. At this point photoactivatable, photoconvertible and photoswitchable fluorescent proteins enter the stage. The members of this fluorescence toolkit can be activated from a non-fluorescent state, they can change their emission spectrum, or they are even able to be reversibly switched "on and off". With the help of these “optical highlighters”, researchers can track a distinct protein population over time by activating respectively converting their fluorescence with a spatially defined light beam of a given wavelength.
    Read article
  • Milestones in Incident Light Fluorescence Microscopy

    Since the middle of the last century, fluorescence microscopy developed into a bio scientific tool with one of the biggest impacts on our understanding of life. Watching cells and proteins with the help of fluorescence molecules is a standard method in nearly every life science discipline today. This broad application range goes back to the technical work of some researchers who wanted to improve and simplify fluorescence microscopic labor. One person who was involved in that development was the Dutch medic Johann Sebastiaan Ploem.
    Read article
  • Chronic Inflammation Under the Microscope

    In the course of chronic inflammation certain body areas are recurrently inflamed. This goes along with many human diseases. With the help of widefield light microscopy, the underlying processes can be examined from a cellular level to whole organisms. This article presents several widefield microscopy applications such as immunofluorescence, live-cell imaging, histology, and ratiometric analysis to get insight into the development of chronic inflammation, the related diseases, and their treatment.
    Read article
  • Factors to Consider When Selecting a Research Microscope

    An optical microscope is often one of the central devices in a life-science research lab. It can be used for various applications which shed light on many scientific questions. Thereby the configuration and features of the microscope are crucial for its application coverage, ranging from brightfield through fluorescence microscopy to live-cell imaging. This article provides a brief overview of the relevant microscope features and wraps up the key questions one should consider when selecting a research microscope.
    Read article
  • Gene Editing with CRISPR/Cas9 - Breakthrough in Genome Engineering

    The CRISPR/Cas9 system is one of several different bacterial systems for defense against viral attacks. It consists of two main components. One is a small piece of RNA which binds to the viral target sequence via Watson-Crick base pairing. It serves as a marker for the foreign nucleic acid. The second component is the Cas9 protein. It binds to the marked sequence and cuts it due to its nuclease activity. Because the base pairing RNA can be synthesized easily and then used to determine a target region, researchers have utilized this system in the laboratory for genome editing.
    Read article
  • Workflows & Protocols: Plant Laser Microdissection

    During Leica workshops for LMD users in Brazil, hosted by the Federal University of Paraná/UFPR (UFPR) at the Centro de Energia Nuclear na Agricultura/USP (CENA), the power of laser microdissection using the Leica LMD systems was demonstrated. One special focus was on plant dissection which needs a high laser power.
    Read article
  • Workflows & Protocols: Laser Microdissection for Pathology and Cancer Research

    Tumor development results from mutations in our DNA. For their deeper analysis, cancer researchers have to dissect the relevant tissue areas. Here we report the reason why laser microdissection is a perfect tool for this purpose and how this was taught in the course of a workshop held in Brazil. With the Leica LMD system pure tumor material can be selected and dissected for downstream analysis to ensure 100% pure starting material without any risk of cross contamination with healthy cells.
    Read article
  • Definitions of Basic Technical Terms for Digital Microscope Cameras and Image Analysis

    Most microscopes today are operated with a camera. The characteristics of the camera often decide whether the acquired image will reveal what a researcher wants to see. But when diving into camera terminology, the technical terms can be overwhelming. We have compiled the most important terms with a concise explanation to provide orientation.
    Read article
  • Infinity Optical Systems

    “Infinity Optics” refers to the concept of a beam path with parallel rays between the objective and the tube lens of a microscope. Flat optical components can be brought into this “Infinity Space” without influencing image formation, which is critical for the utilization of contrast methods such as DIC or fluorescence. Modern microscopy techniques require the addition of multiple optical instruments, such as light sources or laser devices, into the infinite light path. Different approaches to fulfill this need have emerged and are described here.
    Read article
  • Introduction to Digital Camera Technology

    A significant majority of modern optical microscopy techniques require the use of a digital camera. By working with digital devices researchers can observe specimens on a screen in real time or acquire and store images and quantifiable data. Here we introduce the basic principles behind digital camera technologies commonly encountered in scientific imaging.
    Read article
  • Universal PAINT – Dynamic Super-Resolution Microscopy

    Super-resolution microscopy techniques have revolutionized biology for the last ten years. With their help cellular components can now be visualized at the size of a protein. Nevertheless, imaging living cells is a challenge for most of the super-resolution principles.
    Read article
  • GSDIM Publication List

    GSDIM microscopy is a widefield super-resolution technique based on the localization of fluorophores with nanometer precision. With its help a lateral resolution of down to 20 nm can be achieved, whereas the new 3D feature even shrinks axial resolution to 50 nm. Here we provide a collection of publications around that super-resolution microscopy method also called dSTORM.
    Read article
  • Immunotherapy to Combat Cancer: "Sleeping Beauty" – DNA Plasmid-based Gene Transfer System to Modify T Cells

    Fighting cancer is a major goal of present-day medicine. So far mainly surgery, chemotherapy or radiation therapy are utilized to extinguish cancerous tissue, or at least set limits to it. Interestingly the human immune system has effective potential to fight cancer cells. Typically it reacts on parasitic, viral or bacterial infections. Thereby T-cells help to destroy infested cells after binding them via their specific antigen receptor.
    Read article
  • Video Interview with Jean-Luc Vonesch

    Jean-Luc Vonesch is head of the imaging facility at the Institute of Genetics and Molecular and Cellular Biology (IGBMC), Strasburg, France. 23 years ago he was the founder of this facility which nowadays serves more than 850 scientists distributed among 47 working groups. Looking deeply into the cells is of a special interest Vonesch states. And with super-resolution microscopy he pretends it is easier to identify the regions of interest for subsequent electron microscopy: “And so we can gain time thanks to the super-resolution” he says.
    Read article
  • Video Interview with Rainer Pepperkok

    Rainer Pepperkok is Head of the Advanced Light Microscopy Core Facility and Senior Scientist at the EMBL in Heidelberg (Germany). In the course of his studies he is interested in membrane traffic of the early secretory pathway in mammalian cells which he is trying to analyze with the help of most modern light microcopy techniques.
    Read article
  • Video Interview with Werner Zuschratter

    Werner Zuschratter's personal focus is on analyzing the neuronal network, meaning the contacts between nerve cells. Out of this reason he started doing super-resolution microscopy: “It gives us deeper insight into the synapses, into the synaptic machinery, into the molecules we would like to see. Before we could only do electron microscopy and now, with super-resolution, we also have access by light microscopy to the deeper structures inside the nerve system.”
    Read article
  • Video Interview with William Hughes

    William Hughes works at the Garvan Institute of Medical Research, Sydney (Australia). In his Lab Head position he is interested in the causes of diabetes particularly looking at changes in exocytic behavior of pancreatic beta cells as well as fat and muscle cells. TIRF microscopy is predestined for researchers looking at cellular processes near the cytoplasmic membrane.
    Read article
  • Video Interviews with Kees Jalink

    Kees Jalink's group at the Netherlands Cancer Institute in Amsterdam, The Netherlands, explores signal transduction pathways and cell adhesion processes in cancer cells. In his eyes especially the new three-dimensional nanoscopic view of the relevant structure of interest is an essential feature to get the full picture.
    Read article
  • Sample Preparation for GSDIM Localization Microscopy – Protocols and Tips

    The widefield super-resolution technique GSDIM (Ground State Depletion followed by individual molecule return) is a localization microscopy technique that is capable of resolving details as small as 20 nanometers. GSDIM is suitable for a wide range of samples.
    Read article
  • Super-Resolution Microscopy Gives New Insights into Nuclear Pore Complex Organization

    The Nuclear Pore Complex (NPC) is a large complex in the nuclear membrane, representing the gate to the eukaryotic genetic makeup. Because of this outstanding function the structure of the NPC is of great interest. Anna Szymborska, scientist at the EMBL in Heidelberg, comments on her resaerch results and the potential of Ground State Depletion microscopy (GSD) for protein complex analysis in the following interview.
    Read article
  • Deconvolution

    Fluorescence microscopy is a modern and steadily evolving tool to bring light to current cell biological questions. With the help of fluorescent proteins or dyes it is possible to make discrete cellular components visible in a highly specific manner. A prerequisite for these kinds of investigations is a powerful fluorescence microscope. One special aim is the three-dimensional illustration of a structure to get an impression of full plasticity. This poses a certain problem for the experimenter using a classical light microscope.
    Read article
  • Fluorescent Dyes

    A basic principle in fluorescence microscopy is the highly specific visualization of cellular components with the help of a fluorescing agent. This can be a fluorescing protein – for example GFP – genetically linked to the protein of interest. If cloning is impossible – for instance in histologic samples – it is required to use other techniques like immunofluorescence staining to visualize the protein of interest.
    Read article