The images show the cell nucleus and HER2 in exactly the same cells in the same tissue section. The image to the left shows tissue sections with traditional histological staining illustrating the presence of all cells (haematoxylin staining with blue nuclei) in a tissue section. The right image shows the same tissue section with the tumor cells specifically labeled with Lumito’s UCNP (white, HER2 grade 3 (3+) tumor cells).
Current diagnostics and prognostics in clinical histopathology
Diagnosis and prognosis in clinical histopathology is chiefly performed by visual assessment of tissue sections, histochemically stained for cellular structures, for example with H&E, and immunohistochemistry (IHC) in which antibodies mark specific antigens (most often proteins). Commonly pathologists and scientists analyse tissue sections manually using conventional light or fluorescence microscopy. With our cutting-edge technology, immunohistochemically labelled tissue samples are scanned allowing for the samples to be analysed digitally on a computer screen (so-called digital histopathology).
Lumito’s innovative technology
- Our technology is based on an IHC reagent kit, with UCNPs acting as reporters.
The primary antibody is firstly allowed to bind to the targeted antigen, which is then detected by a secondary antibody. - An UCNP conjugate is then attached to the secondary antibody, providing indirect labelling the desired antigen.
- The tissue sample is then illuminated in the Lumito scanner with a near-infrared (NIR) laser whereby the UCNP particles become excited. Upon excitation the UCNP particles emit light at a shorter wavelength which is captured on an image.
- Within the range of excitation wavelengths UCNP becomes excited, no imaging interfering autofluorescence is emitted from the tissue. This yields a stronger contrast compared to traditional solutions.
- Comparable technical solutions available on the market, like fluorescence microscopy (IF), record signal emission from the marker of interest as well as unwanted background, which complicates the tissue analysis and increases the risk of diagnostic errors.
- An important factor making it difficult to analyse IF labelling with currently available instrumentation, is that the light emission from certain fluorophores and that from background autofluorescence are spectrally very close.
The difference between our technology and today’s traditional technology
Unlike instrumentation of today, the instrument platform of Lumito uniquely detects only the IHC-marker of interest. This would enable the technique to at the same time reduce the workload of the pathologist and act to minimize the risk of diagnostic errors.
Unlike conventional fluorescence microscopy, our technique allows for routine or special histochemical staining (like hematoxylin) in parallel with IHC, each of which can be used in the same tissue sample for analysis of tissue morphology and antigen localization.
Additional advantages of UCNP obtained from Lumito:
• Are highly stable
• Do not fade/no photobleaching
• Technique is considered to be more reliable
• Samples can be scanned multiple times
• Stable in storage
• Can be handled in daylight
The images obtained using the UCNPs of Lumito show a higher degree of contrast and resolution compared to images obtained by conventional immunohistochemistry, which would improve the setting conditions for decision support tools based on image analysis and machine learning (AI).
Potential for multiplexing
Our technique also has a strong potential for multiplexing, which involves the use of two or more UCNP markers with different emission wavelengths to label multiple antigens in the same tissue sample. This allows the simultaneous localization of multiple antigens in the same tissue, which has diagnostic advantages.
Multiplexing would importantly reduce the amount of tissue samples requiring preparation. This approach is cost-reducing and a necessity when access to tissue is strongly limited due to inconvenience to the patient and scarcity of tissue. More information from in the same tissue can be obtained, thus contributing to better and safer diagnostics.