The relationship between immune system and cancer is elaborated and dynamic.
Immunotherapy has been acquiring big visibility in recent years and even more in the last months thanks to the 2018 Nobel Prize for medicine (read here). Immunotherapy involves re-engineering T-cells so that they can recognize and kill cancer cells. This type of therapy has shown promising preliminary results in fighting lymphoma.
Microscopy is the elected method to study immune cells interactions and their potential for cancer healing. However, technologies that are available nowadays mainly rely on fluorescence, and fragile primary immune cells are heavily perturbed and eventually killed by staining procedures and phototoxicity.
The research on immune-oncology will greatly benefit from a high-resolution, label-free approach allowing to image immune cells interplays in a marker-free, non-invasive way.
Nanolive’s 3D Cell Explorer opens the door for new observations and for long-term live cell imaging (up to weeks of continuous imaging) with unprecedented spatio-temporal resolution (<200nm; 1img/2sec).
Also, follow this link for more information about how label-free 3D live cell imaging technology changes the future of immune system research: http://2018.nanolive.ch/macrophages/.
Video 1: T-cell activation: APC cells (Macrophages and dendritic cells obtained after isolation and in vitro differentiation of bone marrow cells from C57BL/6 mice) were incubated with freshly isolated naïve T cells and imaged with Nanolive’s 3D Cell Explorer for 11 minutes at a frequency of 1 image every 10 seconds
APC T-cell interaction/activation experiment
In the first movie obtained with Nanolive’s 3D Cell Explorer, we can witness the T-Cell activation process totally marker-free. Pre-stimulated antigen presenting cells (APCs*: dendritic cells and macrophages) are cultured with freshly isolated “naïve T-cells”, the OT-I mice T-cells in order to teach them to recognize and kill tumor cells.
* APCs are special cells that present the antigens on their surface so that other immune cells can “see” and detect it.
T-cells Killing Cancer Cells
In this movie and in the zoom-in below you can see T-Cells killing cancer cells.
The cancer cell line is MC38-OVA, a transduced colon cancer cell line that expresses the ovalbumin (OVA) model antigen.
T-cells, coming from OT-I mice, carry a transgenic T-cell receptor responsive to OVA residues 257-264 (SIINFEKL peptide) in the context of the MHC I H2kb.
In this experiment, the T-cells that were activated in the first experiment and that are now called “effectors”, are incubated with MC38-OVA cancer cells. Upon recognition of their target (the OVA residues on the MHC I H2kB of the cancer cells), T-cells induce the killing of the cancer cells. However, this does not happen all the time and many cancer cells survive.
*Clarke et al. 2000, Immune Cell Biol (https://onlinelibrary.wiley.com/doi/full/10.1046/j.1440-1711.2000.00889.x).
Video 2: Activated T-cells were incubated against the OVA antigen were incubated with MC38-OVA cancer cells expressing the OVA antigen. Cells were imaged for over 6hours at a frequency of 1 image every 20 seconds
Cut of Video 2 zooming on one specific cell. Left panel: 2D Refractive index map and on the right panel 3D reconstruction obtained through digital stain
Video 4: Cut of Video 2 zooming on one specific cell
The Nobel Prize in Physiology or Medicine 2018Discovery of cancer therapy by inhibition of negative immune regulation by James P. Allison & Tasuku Honjo
Nanolive wants to congratulate the 2018 Nobel Prize in Physiology or Medicine who went to James P. Allison and Tasuku Honjo for their discovery of cancer therapy by inhibition of negative immune regulation.
By stimulating the inherent ability of our immune system to attack tumor cells this year’s Nobel Laureates have established an entirely new principle for cancer therapy. James P. Allison studied a known protein that functions as a brake on the immune system. He realized the potential of releasing the brake and thereby unleashing our immune cells to attack tumors. He then developed this concept into a brand new approach for treating patients.
In parallel, Tasuku Honjo discovered a protein on immune cells and, after careful exploration of its function, eventually revealed that it also operates as a brake, but with a different mechanism of action. Therapies based on his discovery proved to be strikingly effective in the fight against cancer. Allison and Honjo showed how different strategies for inhibiting the brakes on the immune system can be used in the treatment of cancer. The seminal discoveries by the two Laureates constitute a landmark in our fight against cancer!
Access to the full press release here (https://www.nobelprize.org/prizes/medicine/2018/press-release/)
Watch a short video obtained with the 3D Cell Explorer showing a cancer cell being killed by a T-cell.
The Perfect Murder – Macrophage Cell Killed by T-cells
The importance of T-cells and macrophages in our immune system
As part of the human immune system, T-cells are designed to identify HLA (Human leukocyte antigens) display proteins that are not part of the normal cell and therefore indicate the presence of a pathogen inside the cell. T-cells circulate in the bloodstream with proteins on their surface termed T-cell receptors. These receptors scan the HLA display proteins looking for a match. The body is equipped with a vast number of T-cells each displaying only one kind of T-cell receptor with the purpose that the variation in the repertory will allow the identification of many kinds of different pathogens. When a given T-cell receptor does fit well with an HLA display protein it signals the adaptive immune system to spring into action and mount an immune response.
Macrophages are a type of white blood cell of the immune system that engulfs and digests cellular debris, foreign substances, microbes, cancer cells, and anything else that does not seem to be a healthy body cell.
The perfect murder – Macrophage cell killed by T-cells
In this movie, we can observe macrophages and T-cells interacting. Naive T-cells are being presented with antigens by the macrophages which “instruct” T-cells on what type of cells to target (such as cancer cells) and kill. During this interaction, T-cells can play a role in immune system homeostasis (Andersen, 2018) by killing the macrophage presenting the antigen. It was documented that the event is triggered by the presence of specific markers on the macrophage surface (called TRAIL and TWEAK (Kaplan et al., 2018)) telling T-cells to induce apoptosis of their fellow macrophage. The dead macrophage is then seen to be recycled by other macrophages, making space for new macrophages to be produced while keeping the same overall macrophage population.
In this video, pre-stimulated antigen presenting cells (APCs, namely dendritic cells and macrophages, obtained after isolation and in vitro differentiation of bone marrow cells from C57BL/6 mice, pre-stimulation of the APCs has been done with IFN-gamma and LPS) are cultured with freshly isolated “naïve T cells” from the spleen of OT-I mice and observed at a frequency of 1 image every 10 sec for 16 hours.*
*All primary cells were freshly isolated from mice (C57BL/6 background). Naïve t-cells were also obtained from OT-I mice.
Webinar: Label-free live cell imaging meets Immuno-oncology
Dr. Mathieu Frechin, Head of Quantitative Biology at Nanolive will introduce you to our holotomographic microscopy and its implications in the field of Immuno-Oncology. During the webinar he will discuss the opportunities that are created by the usage of Nanolive’s label-free technology in the field of immune system research. In particular, the following topics will be covered:
- Immuno-oncology in the spotlight – strategic importance of studying the immune system.
- Current state of the art of live cell imaging in the field of immunology – what Nanolive’s technology can bring to the field.
- New live cell research possibilities to understand the cell-cell interactions of the immune system (examples).
Application Note: When Holotomography Meets Immuno-Oncology
In this application note we will discuss new research possibilities that arise from combining holotomography and immuno-oncology, which is more than ever in the spotlight.