MEMS cytometer for porcine oocyte deformation measurement

Abstract

Mechanical properties of cells are indicators of biological potential, quality and presumptive pathological status. Mammalian oocytes are particularly important cells from the point of view of testing their fertilizing potential and performing in vitro fertilization. However, only occasionally are their mechanical parameters measured.A new method for deformation measurement of in vitro-matured porcine oocytes has been developed and presented in this study. The method was used for multiparametric characterization of gametes using a MEMS-type microcytometer and a new methodology for determining cell deformability. The novel chip design, principle of operation, and fabrication processes are described in the study. Using original analysis of microscopic images with the usage of dedicated software and data analysis algorithms, deformation parameters were determined. Results indicate the relationships between parameters under the influence of cell compression and show that the behaviour of oocytes during measurements depends on the morphological quality of the cumulus-oocyte complexes they originated from.

Microfluidic chip as a promising evaluation method in assisted reproduction: A systematic review

“…Twenty studies characterized oocytes using microfluidics (Table 1). 56,[69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84][85][86][87] Microfluidic chips can measure large numbers of oocytes with high throughput and sensitivity. 88 Seven studies deformed oocytes to test their mechanical properties (Figure 4a-d), [69][70][71][72][73][74][75] including one that applied injection force to test oocyte mechanics (Figure 4c), 70 and three that used compression force.…”

“…56,[69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84][85][86][87] Microfluidic chips can measure large numbers of oocytes with high throughput and sensitivity. 88 Seven studies deformed oocytes to test their mechanical properties (Figure 4a-d), [69][70][71][72][73][74][75] including one that applied injection force to test oocyte mechanics (Figure 4c), 70 and three that used compression force. Six studies utilized microfluidic tools to investigate cellular membrane permeability to cryoprotectants (CPAs; Figure 4e), 56,[76][77][78][79][80] which are associated with cryopreservation efficacy.…”

Lab-on-Chip Platform for Culturing and Dynamic Evaluation of Cells Development

“…An optical detection system on the platform (CCD camera, model: DLT-Cam PRO, Delta Optical, Warsaw, Poland) ensured constant observation of cells. On the basis of the acquired sample data, smart image processing could be initialized utilizing authorial software [31,32]. The implemented algorithms (edge and blob detection, cell tracking) provided cell detection and tracking at the single cell level, resulting in a complete characterization of the cultures in the context of population number, as well as cells' size, shape, eccentricity, mobility, movement trajectory, and so on.…”

10 μm thick ultrathin glass sheet to realize a highly sensitive cantilever for precise cell stiffness measurement

“…[1][2][3][4][5] The measurement of cell mechanical properties is key to understanding many complex biological processes and has attracted widespread interest in different fields, including human disease diagnosis, [6][7][8] drug treatment evaluation, 9 and embryo development prediction. [10][11][12] For example, changes in the stiffness of cells are often signs of changes in cell physiology or diseases in tissues. 13 More recently, stiffness has emerged as a new potential biomarker to predict fertilization and embryo development.…”

“…13 More recently, stiffness has emerged as a new potential biomarker to predict fertilization and embryo development. 11,12,[14][15][16][17] In particular, the fertilization and embryo transfer condition could be conducted by measuring the stiffness as early as the oocyte stage, reducing unnecessary culture time while increasing the pregnancy rate and efficiency. Stiffness biomarkers also open up a new way of oocyte quality prediction, allowing physicians to have a better understanding of which oocytes need to be collected for fertilization and evaluation of the effectiveness of hormonal stimulation protocols.…”