Cell-Laden Thermosensitive Chitosan Hydrogel Bioinks for 3D Bioprinting Applications
, Kyoung-Je Jang 1, Juo Lee 2, Myungchul Lee 1, Jae Woon Lim 1, Jangho Kim 3 and Jong Hoon Chung 1,4,*Round 1
Reviewer 1 Report
It is an interesting paper using Chitosan hydrogel as the bioink for 3D printing. The paper is well written. After addressing below questions, it can be considered for publishing:
- The figure quality needs to be improved. Such as the Figure 2 c, it will not be able to tell the temperature changing range.
- From figure 3, the cells were seeded in the cavity of 3D printed mesh network. The figure 3D showed the growth of cells themselves, without much contact with scaffolding materials. Thus, such cell viability testing may not represent the real influence of scaffolding materials on cell growth. It would be good to show confocal images and MTT assay with longer term of culture for illustrating the cellular interaction with scaffolding structures and surface chemistry to prove the cell viability and biocompatibility.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper described a 3D hydrogel for cell encapsulation using 3D bioprinting. Different solvent and gelling agent were tried for hydrogel preparation and bioprinting. The work is very neat and interesting. It would be more attractive if different cell types or hydrogels included in future. However, more details about the printer and the PDLSCs encapsulation print should be provided. SEM images of printed CS scaffolds should be provided. Please also specify the significance of your hydrogels or printed scaffolds in tissue engineering or biomedical engineering.
Line 67-68 “Cell viability of extrusion bioprinter is lower than inkjet bioprinter, but extrusion bioprinting is able to deposit very high cell densities at a reasonable cost.” – please insert a reference here.
Line 74 “However, most hydrogels use crosslinkers which can cause in cell viability” – did the author miss some words here? cause cell death or viability?
Line 76 “transits into gel” should be “transit into gels”
Figure 1B – the image on the right bottom is hard to read and the shape of the vials is odd.
Figure 1C – what is the meaning of the circles in the Figure 1C that close to x-axis?
Figure 1D – it would be better to include all results from day 1 to day 5 in one graph which is easy to compare. Also, there is a control missing in all graphs.
Figure 2A- same problem as above in Figure 1B
Figure 2B - same problem as above in Figure 1C
Line 188-189 “CS/K2HPO4 group observed the large size precipitation that might be induce nozzle clogging during the 3D printing.” – please address an explanation here.
Figure 2E - same problem as above in Figure 1D
Figure 2F – the cell density looks very low – please explain it.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The authors have changed the title, which clarified the significance of this work better than before. The updated figures are much better organized to describe the results. It would be more interesting to include confocal images. However, considering the current situation around the world, I fully understand what the author's suggestion.
