Live cardiomyocyte imaging via hybrid TPEF-SHG microscopy

Abstract

Utilizing a custom-built, on-stage incubator-combined, two-photon excitation fluorescence (TPEF) and second harmonic generation (SHG) imaging system, we observed new-sarcomere addition in rat neonatal cardiomyocytes during 10 hours of on-stage incubation. This addition occurred at one end of an existing myofibril, the sides of existing myofibrils, and at the interstice of several separated myofibrils; in the cases of the latter two, we observed mature myofibrils acting as templates. We found that during sarcomeric addition, myosin filaments are assembled onto the premyofibril laterally. This lateral addition, which proceeds stepwise along the axial direction, plays an important role in the accumulation of Z-bodies to form mature Z-disks and in the regulation of sarcomeric length during maturation.

Multimodal imaging of harmonophores and application of high content imaging for early cancer detection

“…Common examples of SHG active molecules, known as harmonophores are collagen types I and III, myosin (when present within acto-myosin complexes), and cholesterol crystals (ChC) which are chiral in nature. [8,9,10] Studies conducted by Su et al [11] have shown that extracellular matrix (ECM) alterations are a very important indicator for different kinds of tumour growth within corneal, colonic, cardiac, breast, and ovarian tissues. Intensity based SHG imaging can yield clear images of the modifications of the tissue structure, by elucidating collagen orientation changes in the ECM, as can be seen in Figure 3, which is an image taken of a sub-dermal tumour in a mouse, from the studies conducted by Brown.…”