Cell type related differences in staining with pentameric thiophene derivatives

Abstract

Fluorescent compounds capable of staining cells selectively without affecting their viability are gaining importance in biology and medicine. Recently, a new family of optical dyes, denoted luminescent conjugated oligothiophenes (LCOs), has emerged as an interesting class of highly emissive molecules for studying various biological phenomena. Properly functionalized LCOs have been utilized for selective identification of disease-associated protein aggregates and for selective detection of distinct cells. Herein, we present data on differential staining of various cell types, including cancer cells. The differential staining observed with newly developed pentameric LCOs is attributed to distinct side chain functionalities along the thiophene backbone. Employing flow cytometry and fluorescence microscopy we examined a library of LCOs for stainability of a variety of cell lines. Among tested dyes we found promising candidates that showed strong or moderate capability to stain cells to different extent, depending on target cells. Hence, LCOs with diverse imidazole motifs along the thiophene backbone were identified as an interesting class of agents for staining of cancer cells, whereas LCOs with other amino acid side chains along the backbone showed a complete lack of staining for the cells included in the study. Furthermore, for p-HTMI,a LCO functionalized with methylated imidazole moieties, the staining was dependent on the p53 status of the cells, indicating that the molecular target for the dye is a cellular component regulated by p53. We foresee that functionalized LCOs will serve as a new class of optical ligands for fluorescent classification of cells and expand the toolbox of reagents for fluorescent live imaging of different cells.

Real-time optotracing of curli and cellulose in live Salmonella biofilms using luminescent oligothiophenes

“…Recent studies have also shown that specificity towards distinct biomolecular targets can be achieved by adding proper β-side chain functionalities along the thiophene backbone and that replacement of the central thiophene moiety with other heterocyclic moieties can generate a palette of LCOs with distinct emission profiles covering the visual spectrum. 37,38 Overall, we foresee that similar chemical modifications of the LCOs will be extremely useful for overpowering potential limitations of the method.…”

Nuclear localized Akt enhances breast cancer stem-like cells through counter-regulation of p21Waf1/Cip1and p27kip1

“…13 Some types of (cancer) stem cells may even be differentially visualized by certain fluorescent dyes. 34,35 Even though fewer in numbers, cancer stem-like cells show resistance to currently available radiation and chemotherapeutic interventions and thus cause cancer reoccurrence. Previous studies revealed that the PI3K/Akt pathway plays a pivotal role in oncogenesis by inhibiting pro-apoptotic signaling molecules and maintaining pluripotency among murine and cynomolgus monkey embryonic stem cells.…”

Differential vital staining of normal fibroblasts and melanoma cells by an anionic conjugated polyelectrolyte

“…In addition, a thiophene based probe that selectively stains tumor-associated cells would be desirable. Lately, chemically defined luminescent conjugated oligothiophenes, LCOs, have been developed (53)(54)(55) and LCOs with diverse imidazole motifs along the thiophene backbone were identified as an interesting class of agents for staining of cancer cells (55). Thus, it will be of great interest to study their impact and target more in detail within different cell types, as well as their potential for being utilized for PDT.…”