Holography: The Usefulness of Digital Holographic Microscopy for Clinical Diagnostics

Digital holographic (DH) microscopy is a digital high-resolution holographic imaging technique with the capacity of quantification of cellular conditions without any staining or labeling of cells. The unique measurable parameters are the cell number, cell area, thickness, and volume, which can be coupled to proliferation, migration, cell cycle analysis, viability, and cell death. The technique is cell friendly, fast and simple to use and has unique imaging capabilities for time-lapse investigations on both the single cell and the cell-population levels. The interest for analyzing specifically cell volume changes with DH microscopy, resulting from cytotoxic treatments, drug response, or apoptosis events has recently increased in popularity. We and others have used DH microscopy showing that the technique has the sensitivity to distinguish between different cells and treatments. Recently, DH microscopy has been used for cellular diagnosis in the clinic, providing support for using the concept of DH, e.g., screening of malaria infection of red blood cells (RBC), cervix cancer screening, and sperm quality. Because of its quick and label-free sample handling, DH microscopy will be an important tool in the future for personalized medicine investigations, determining the optimal therapeutic concentration for both different cancer types and individual treatments

Cells and Holograms – Holograms and Digital Holographic Microscopy as a Tool to Study the Morphology of Living Cells

We present a method to study the morphology of living, dividing and dying cells using DHM. DHM is a non-invasive, non-destructive and non-phototoxic method which allows the user to perform both qualitative and quantitative measurements of living cells over time. We show here our results on cell division and cell death in single cells. The morphological analyses performed here show changes caused by cell death and cell division, and indicate the possibilities to discriminate between different types of cell death. Cells dying in an apoptosis-like manner display different cell area and cell thickness profiles over time compared to cells dying in a necrosis-like manner, although their volume profiles are very similar. Dividing cells show a characteristic dip in the volume profile, which makes them easily distinguishable. Also, several previous studies show the versatile abilities of DHM. Different cell types have been studied and the morphology has been used to determine cell functionality as well as changes in morphology related to the environment. Cell morphology parameters can be very useful when following the effects of different treatments, the process of differentiation as well as cell growth and cell death. Cell morphology studied by DHM can be useful in toxicology, stem cell and cancer research

Novel imaging technology and tools for biomarker detection in cancer

Cancer is a leading cause of death worldwide. Normally the balance betweencell growth and cell death is strongly controlled. Chronic lymphocytic leukemiais an indolent disease that has a highly variable clinical course and is the mostcommon hematological malignancy amongst adults in the Western countries.The protein tyrosine phosphatase SHP-1 is a key regulator that controls theintracellular phosphotyrosine level in lymphocytes by inhibiting the B cell receptorsignals. We have compared the expression and activity of SHP-1 inchronic lymphocytic leukemia cells from lymph nodes with matched peripheralblood samples. The expression levels of SHP-1 were higher in peripheral blood,but the phosphatase activity in lymph nodes and peripheral blood did not differsignificantly. All cells in the body normally present glycans on the cell surface,which are involved in cellular communication and in processes like cell differentiation,proliferation and infection, including protecting the cells from invadersand in cell-cell contacts. Sialic acid occurs on the terminal end of glycans,and the frequency of sialic acid expression is increased on metastatic cancer cellsand overexpression controls tumor cell growth and cell differentiation. Theavailability of specific antibodies against sialic acid is limited. We have beenscreening sialic acid on cancer cells by using a molecular imprinting polymertechnique. Our results show that sialic acid is expressed on chronic lymphocyticleukemia cell lines at different levels at the plasma membrane. Higher expressionof sialic acid in the more aggressive chronic lymphocytic leukemia cell lineswas observed. To analyze morphological changes of death cells, digital holographicmicroscopy was used. Digital holographic microscopy is an approachfor label-free non-invasive 3D imaging of cultured cells. We have analyzed celldeath of adherent cancer cells using digital holographic microscopy and developedit to analyze suspension cells by combining this technique with antibodybased microassays. Digital holographic microscopy can be used for cell-deathinduced cell analysis of both adherent cells and suspension cells. This thesistakes us one step further in cancer research as regards developing techniques forscreening circulating cancer cells in blood as well as for individualized treatmentof cancer patients

Digital holographic microscopy : a noninvasive method to analyze the formation of spheroids

Digital holographic (DH) microscopy is a unique noninvasive method to analyze living cells. With DH microscopy, in vitro cell cultures can be imaged in 2D and pseudo-3D and measurements of size and morphology of the cells are provided. Here, a description of a novel methodology utilizing DH microscopy for the analysis of spheroids is presented. A cell culture protocol is introduced and morphological parameters of cell spheroids as measured by DH microscopy are presented. The study confirms the use of DH microscopy for the analysis of cell spheroids. In the future, organoids can be analyzed with DH microscopy, and it can also be used for drug response and cell death analyses. Method summary This method aims to optimize DH microscopy for the analysis of morphological parameters of spheroids in an easy and convenient way. Cell spheroids were cultured in culture dishes for 5 days. Then, the lid was replaced with HoloLid. After that, the spheroids were imaged and quantitative morphological information was collected and analyzed

Novel imaging technology and tools for biomarker detection in cancer

Cancer is a leading cause of death worldwide. Normally the balance between cell growth and cell death is strongly controlled. Chronic lymphocytic leukemia is an indolent disease that has a highly variable clinical course and is the most common hematological malignancy amongst adults in the Western countries. The protein tyrosine phosphatase SHP-1 is a key regulator that controls the intracellular phosphotyrosine level in lymphocytes by inhibiting the B cell receptor signals. We have compared the expression and activity of SHP-1 in chronic lymphocytic leukemia cells from lymph nodes with matched peripheral blood samples. The expression levels of SHP-1 were higher in peripheral blood, but the phosphatase activity in lymph nodes and peripheral blood did not differ significantly. All cells in the body normally present glycans on the cell surface, which are involved in cellular communication and in processes like cell differentiation, proliferation and infection, including protecting the cells from invaders and in cell-cell contacts. Sialic acid occurs on the terminal end of glycans, and the frequency of sialic acid expression is increased on metastatic cancer cells and overexpression controls tumor cell growth and cell differentiation. The availability of specific antibodies against sialic acid is limited. We have been screening sialic acid on cancer cells by using a molecular imprinting polymer technique. Our results show that sialic acid is expressed on chronic lymphocytic leukemia cell lines at different levels at the plasma membrane. Higher expression of sialic acid in the more aggressive chronic lymphocytic leukemia cell lines was observed. To analyze morphological changes of death cells, digital holographic microscopy was used. Digital holographic microscopy is an approach for label-free non-invasive 3D imaging of cultured cells. We have analyzed cell death of adherent cancer cells using digital holographic microscopy and developed it to analyze suspension cells by combining this technique with antibody based microassays. Digital holographic microscopy can be used for cell-death induced cell analysis of both adherent cells and suspension cells. This thesis takes us one step further in cancer research as regards developing techniques for screening circulating cancer cells in blood as well as for individualized treatment of cancer patients

CD22 (CD22 molecule)

Sialic acid binding immunoglobulin-type lectin (Siglec) family are inhibitory receptors with diverse roles in the immune system. Siglec family contains 14 members in human and 9 in murine. Differentially expressed on various white blood cells. Here in this review we are focusing on CD22, also known as Sialic Acid-Binding Ig-Like Lectin 2 (Siglec-2). CD22 gene is located on 19q13.12 and is encoding a 140 kD type I transmembrane glycoprotein on the surface of B cells and is part of the immunoglobulin (Ig) superfamily and has been found only on B cells. CD22 has been shown to play a major role in establishing a baseline level of B-cell inhibition, and thus is a critical determinant of homeostasis in humoral immunity

ZAP70 (zeta-chain (TCR) associated protein kinase 70kDa)

Review on ZAP70, with data on DNA, on the protein encoded, and where the gene is implicated

Quantitative Phase Imaging for Label-Free Analysis of Cancer Cells—Focus on Digital Holographic Microscopy

To understand complex biological processes, scientists must gain insight into the function of individual living cells. In contrast to the imaging of fixed cells, where a single snapshot of the cell’s life is retrieved, live-cell imaging allows investigation of the dynamic processes underlying the function and morphology of cells. Label-free imaging of living cells is advantageous since it is used without fluorescent probes and maintains an appropriate environment for cellular behavior, otherwise leading to phototoxicity and photo bleaching. Quantitative phase imaging (QPI) is an ideal method for studying live cell dynamics by providing data from noninvasive monitoring over arbitrary time scales. The effect of drugs on migration, proliferation, and apoptosis of cancer cells are emerging fields suitable for QPI analysis. In this review, we provide a current insight into QPI applied to cancer research

Det digitala holografiska mikroskopet : innovativ teknik för analys av levande celler

Bakgrund: Digital holografi är en ny teknik som de senaste fem åren använts för att studera levande celler. Tekniken utgör en innovativ, icke-förstörande metod som möjliggör studier av levande celler över tid. Material och metoder: Litteraturen har valts ut genom att söka på redan kända forskargrupper och företag som arbetar både med digital holografi och cellstudier samt PubMed-sökningar. Resultat och sammanfattning: Digital holografi ger kunskap om cellernas brytningsindex, som kan ändras under olika förhållanden. De parametrar som kan mätas ger unik information om cellantal, cellernas area, tjocklek och volym, vilket kan omvandlas till proliferation, viabilitet och celldöd. Tekniken är relativt billig, snabb och enkel att använda.Background: Digital holography is a novel technique that has been used for about five years to study living cells. The technique is an innovative, non-destructive method with possibilities to study living cells over time. Materials and methods: The literature in this paper was selected on the basis of already known research groups and companies in the field working with both digital holography and cell studies, as well as PubMed search. Results and conclusions: Digital holography is a method that gives us information about the refractive index of cells, which can change under different circumstances. The unique measurable parameters are the cell number, cell area, thickness and volume, which can be transformed to proliferation, viability and cell death. The technique is cheap, fast and simple to use