Immunoinformatics Insights into the Internalin A and B Proteins to Design a Multi-Epitope Subunit Vaccine for L. monocytogenes

International Journal of Peptide Research and Therapeutics - Amino acids are the principal constituent of peptides and proteins. The ever-going expansion beyond non-canonical amino acids is one of...     

Hybrid poly-l-lactic acid/poly(ε-caprolactone) nanofibrous scaffold can improve biochemical and molecular markers of human induced pluripotent stem cell-derived hepatocyte-like cells

A suitable alternative strategy for liver transplantation is the use of nanofibrous scaffolds together with stem cells. In this study, a random hybrid of poly-l -lactic acid (PLLA) and poly(ε-caprolactone) (PCL) was used as a three-dimensional (3D) culture for differentiation of hepatocyte-like cells and compared with routine culture (two-dimensional [2D]). The expression of the endodermal marker, forkhead box A2 (FOXA2), was assessed on Day 3 and the hepatic markers; albumin (ALB), α-1 antitrypsin (AAT), and cytokeratin-18 (CK-18) were evaluated on Day 18 using quantitative polymerase chain reaction qPCR. As well as, ALB, α-fetoprotein (AFP), and low-density lipoprotein (LDL) uptake were evaluated using immunocytochemistry; moreover, periodic acid-Schiff and Oil Red were done by cell staining. In addition, AFP and urea production were evaluated by chemiluminescence and colorimetric assays. Light and scanning electron microscopy (SEM) showed changes in the cells in 2D and 3D models. The gene expression of hepatic markers was significantly higher in the 3D cultures. In addition, immunocytochemistry and cell staining showed that ALB, AFP, LDL-uptake, periodic acid-Schiff, and Oil Red were expressed in both cells derived on 2D and 3D. Furthermore, the evaluation of AFP and urea secretion was significantly different between 2D and 3D strategies. These findings suggest that functionally cells cultured on a PLLA/PCL scaffold may be suitable for cell therapy and regenerative medicine.     

Macrophage cell morphology-imprinted substrates can modulate mesenchymal stem cell behaviors and macrophage M1/M2 polarization for wound healing applications

Mesenchymal stem cells and macrophages (MQ) are two very important cells involved in the normal wound healing process. It is well understood that topological cues and mechanical factors can lead to different responses in stem cells and MQ by influencing their shape, cytoskeleton proliferation, migration, and differentiation, which play an essential role in the success or failure of biomaterial implantation and more importantly wound healing. On the other hand, the polarization of MQ from proinflammatory (M1) to prohealing (M2) phenotypes has a critical role in the acceleration of wound healing. In this study, the morphology of different MQ subtypes (M0, M1, and M2) was imprinted on a silicon surface (polydimethylsiloxane [PDMS]) to prepare a nano-topography cell-imprinted substrate with the ability to induce anti-inflammatory effects on the mouse adipose-derived stem cells (ADSCs) and RAW264.7 monocyte cell line (MO). The gene expression profiles and flow cytometry of MQ revealed that the cell shape microstructure promoted the MQ phenotypes according to the specific shape of each pattern. The ELISA results were in agreement with the gene expression profiles. The ADSCs on the patterned PDMS exhibited remarkably different shapes from no-patterned PDMS. The MOs grown on M2 morphological patterns showed a significant increase in expression and section of anti-inflammatory cytokine compared with M0 and M1 patterns. The ADSCs homing in niches heavily deformed the cytoskeletal, which is probably why the gene expression and phenotype unexpectedly changed. In conclusion, wound dressings with M2 cell morphology-induced surfaces are suggested as excellent anti-inflammatory and antiscarring dressings.