Technological platforms at CIM

The Center for Infectious Medicine has invested a significant amount of economic resources to amass cutting edge technology and scientific expertise. CIM offers advanced equipment for visualization and quantification of immune cell functions, as well as advanced flow cytometry. Researchers at CIM also have developed methods for isolating large numbers of specific primary cells and experimental In vivo models.

Research environment, CIM
CIM provides researchers with front-line imaging technology Photo: Peter Holgersson

Imaging at the cellular and tissue level

To perform complete studies of immunological and pathogenic mechanisms, it is essential to have advanced equipment for visualization and quantification of immune cell functions.

At CIM, researchers have established an advanced visualization facility that provides researchers with front-line imaging technology, technical support and imaging-related expert advice to researchers. Specific acquired computerized image analyses programs for quantification of biological and immunological mediators have been developed in the research environment.

CIM also holds advanced equipment for fluorescence microscopy analyses, including a Nikon A1R confocal microscope, which is an excellent tool for studies of immune cell functions, viral and bacterial entry into host cells, as well as intracellular vesicular transport and diffusion mechanisms. It allows studies of single molecule dynamics, surface structures, exocytic and endocytic trafficking, receptor/ligand and cell-cell interactions in living and fixed specimens. The Nikon A1R is equipped with the total internal reflection fluorescence (TIRF) application, which is an ideal tool for live imaging investigating both the mechanisms and dynamics of protein interactions at the cell membrane surface.

As a joint effort with S. Strömblad and R. Toftgård at the Novum Research Center in Huddinge, CIM has established a state-of-the art imaging facility. The facility offers a wide range of microscopes for advanced fluorescence microscopy and includes a multiphoton confocal microscope Zeiss 710, which allows extended time lapse experiments on live cells.

This includes four-dimensional (4D, i.e. 3D over time) imaging of dynamic cellular events and quantitative modeling of molecular mechanisms regulating immune cell behavior in more complex settings such as, e.g., organotypic cultures, tissue explants, and whole body organs. This microscope allows simultaneous analyses of a range of fluorophores and also provides a cutting edge technology for imaging of live human immune cells and host pathogen interactions under more physiological conditions.

Tissue model systems

At CIM, researchers have access to unique biopsies from patient cohorts.

Analyses of sections or isolated cells from biopsies at the cellular or molecular level provide information of high clinical relevance that are further strengthened by detailed analyses in appropriate human cell and tissue model systems.

From simple co-culture models of human tissue cells and, ultimately, to the generation of whole organs or representations of whole organs in the laboratory, scientists in the research environment develop human tissue model systems in vitro that can complement essential work currently achievable only in vivo.

Our commitment to this development is essential. It includes specialized cultures of tissue cells as well as ex vivo explant models. Several approaches have been adapted to study immune cell interactions with tissue specific cells in monolayer-based cultures. Although these culture systems have provided important information with respect to tissue-specific influences on immune cell function, moving from cell monolayers to three-dimensional (3D) cultures is motivated by the need to work with cellular models that mimic the functions of living tissues.

Scientists in the research environment engineer three-dimensional (3D) tissue models, so-called organotypic cultures that also contain immune cells. Our approach of developing and using 3D tissue models that mimic real tissues provides unique tools to study human immune cell functions that are present in live tissue and often missed in monolayer-based cell cultures.

In 3D cultures, tissue specific cells acquire a polarized phenotype and a large number of cell-cell contacts occur, which are likely to affect immune cell function and responses to external stimuli, such as pathogens. In addition, the 3D tissue model allows performance of live imaging of immune cells within tissue using 4D, i.e. 3D over time fluorescence imaging techniques. For this purpose we generate tissue models with fluorescent cells, e.g. epithelial cells, fibroblasts, dendritic cells and monocytes.

Thus, creating tissue models with immune cells provide us with a technological platform to increase our understanding of human immune cell responses, migration and positioning in tissue, in addition to interactions with pathogens in more physiological models.

For more information please contact:

Mattias Svensson

Researcher
H7 Department of Medicine, Huddinge
Advanced flow cytometry, CIM
Advanced flow cytometry at CIM Photo: Peter Holgersson

Advanced flow cytometry

Researchers at CIM have been at the leading edge since 2003 in the field of flow cytometry technology.

The advanced flow cytometry lab at CIM is equipped with two BD LSR Fortessa instruments with four lasers that allows assessment of up to 18 fluorescence parameters simultaneously. This technology allows characterization of immune cell subsets at high resolution in exquisite detail, and the value of rare patient samples can be maximized.

The instruments are currently used by many groups in the environment in research related to human immune cell function and infectious diseases.

For more information please contact:

Jakob Michaelsson

Researcher
H7 Department of Medicine, Huddinge
Research environment at CIM Photo: Peter Holgersson

Large-scale isolations of human cells

To study functional aspects of human immune cells it is crucial to have efficient methods of obtaining primary human cells.

Researchers at CIM have developed several sophisticated methods for isolating large numbers of specific primary cells. As an example, our researchers now isolate human hematopoietic progenitor cells (HPC) from bone marrow and cord blood.

A number of other cell isolation systems have been established within CIM for isolation of large numbers of differentiated cells.

For more information please contact:

Jenny Mjösberg

Researcher
H7 Department of Medicine, Huddinge

In vivo models

Experimental models constitute an important complement to in vitro experiments and studies on patient material.

Researchers at the CIM use experimental models with an aim to gain increased understanding for complex host-microbe interactions, disease mechanisms and for testing new vaccine- and drug candidates. CIM is also actively involved in the generation of needs-driven, novel in vivo models for studies within these and related research areas.