User:Jneyyan/Microcarrier/Lisa1235858 Peer Review

General info

 * Whose work are you reviewing?

Jneyyan


 * Link to draft you're reviewing

Microcarrier


 * Link to the current version of the article (if it exists)

Microcarrier

Evaluate the drafted changes
(Compose a detailed peer review here, considering each of the key aspects listed above if it is relevant. Consider the guiding questions, and check out the examples of what feedback looks like.)

Lead
Guiding questions:


 * Has the Lead been updated to reflect the new content added by your peer?
 * Yes it has
 * Does the Lead include an introductory sentence that concisely and clearly describes the article's topic?
 * Yes it does
 * Does the Lead include a brief description of the article's major sections?
 * Yes it does
 * Does the Lead include information that is not present in the article?
 * Yes it does
 * Is the Lead concise or is it overly detailed?
 * I feel like the lead could be cut down a little, but it is a good lead

Content
Microcarrier composition

There are several types of microcarriers that can be used, the selection of which is crucial for optimal performance for the application. Early in microcarrier development history, synthetic materials were overwhelmingly used, as they allowed for easy control of mechanical properties and reproducible results for the evaluation of their performance. These materials include DEAE-dextran, glass, polystyrene plastic, and acrylamide. However, synthetic polymers prevent sufficient cell interactions with their environment and stunts their growth. Cells may not differentiate properly without feedback from their environment, and attachment levels would be low. Therefore, the second generation of microcarrier development involves use of natural polymers such as gelatin, collagen, chitin and its derivatives, and cellulose (5). Not only are these materials easily obtained, but the natural materials provide attachment sites for cells and a similar microenvironment that provides the cell signaling pathways necessary for their proper differentiation. Furthermore, as these are biocompatible, the resulting suspension can be used for delivery of cell therapies in vivo (6).

Although liquid microcarriers have been developed, a large majority of commercially available microcarriers are solid particles, synthesized through suspension polymerization. However, cells grown on solid microcarriers risk damage from shear stress and collisions with other particles and the tank. Therefore, extra precaution must be taken on determining the stir speed and mechanism, so that the resulting fluid dynamic forces are not strong enough to adversely affect culture. The development of porous microcarriers greatly expanded the capabilities of this technology as it further increased the number of cells that the material can hold, but more importantly, it shielded those within the particle from external forces. These include drag and frictional forces of the suspension fluid, pressure gradients, and shear stresses (2).

Several types of microcarriers are available commercially including alginate-based (GEM, Global Cell Solutions), dextran-based (Cytodex, GE Healthcare), collagen-based (Cultispher, Percell), and polystyrene-based (SoloHill Engineering) microcarriers. They differ in their porosity, specific gravity, optical properties, presence of animal components, and surface chemistries. Surface chemistries can include extracellular matrix proteins, functional groups, recombinant proteins, peptides, and positively or negatively charged molecules, added through conjugation, co-polymerization, plasma treatment or grafting. These may serve to provide higher attachment levels of the cells to the particles, provide a controlled release for isolation, or make the particles more thermally and physically resistant, among other reasons.

Guiding questions:


 * Is the content added relevant to the topic?
 * Yes
 * Is the content added up-to-date?
 * Yes
 * Is there content that is missing or content that does not belong?
 * No
 * Does the article deal with one of Wikipedia's equity gaps? Does it address topics related to historically underrepresented populations or topics?
 * Not applicable

Tone and Balance
Guiding questions:


 * Is the content added neutral?
 * Yes
 * Are there any claims that appear heavily biased toward a particular position?
 * No
 * Are there viewpoints that are overrepresented, or underrepresented?
 * No
 * Does the content added attempt to persuade the reader in favor of one position or away from another?
 * No

Sources and References
Guiding questions:


 * Is all new content backed up by a reliable secondary source of information?
 * The new content appears to derive most of it information from a secondary source
 * Does the content accurately reflect what the cited sources say? (You'll need to refer to the sources to check this.)
 * Yes the content does reflect the cited sources
 * Are the sources thorough - i.e. Do they reflect the available literature on the topic?
 * The sources are thorough, one of them explains the past, present, and future of Microcarrier based tissue engineering
 * Are the sources current?
 * The sources are current
 * Are the sources written by a diverse spectrum of authors? Do they include historically marginalized individuals where possible?
 * Not applicable
 * Are there better sources available, such as peer-reviewed articles in place of news coverage or random websites? (You may need to do some digging to answer this.)
 * The sources they currently have are good
 * Check a few links. Do they work?
 * The links work

Organization
Guiding questions:


 * Is the content added well-written - i.e. Is it concise, clear, and easy to read?
 * Does the content added have any grammatical or spelling errors?
 * Is the content added well-organized - i.e. broken down into sections that reflect the major points of the topic?

Images and Media
Guiding questions: If your peer added images or media


 * Does the article include images that enhance understanding of the topic?
 * It includes a table that describes various commercially available microcarriers
 * Are images well-captioned?
 * Not applicable
 * Do all images adhere to Wikipedia's copyright regulations?
 * Not applicable
 * Are the images laid out in a visually appealing way?
 * Not applicable

Overall impressions
Guiding questions:


 * Has the content added improved the overall quality of the article - i.e. Is the article more complete?
 * Yes
 * What are the strengths of the content added?
 * The advantages of microcarrier technology in the vaccine industry include (a) ease of scale-up, (b) ability to precisely control cell growth conditions in sophisticated, computer-controlled bioreactors, (c) an overall reduction in the floor space and incubator volume required for a given-sized manufacturing operation, and (d) a drastic reduction in technician labor. --Good ending to your lead
 * How can the content added be improved?
 * A microcarrier is a type of support matrix that allows for the growth of adherent cells in bioreactors (typically stirred-tank bioreactors). These spherical matrices range anywhere between 100-300 um in diameter to allow sufficient surface area while retaining enough cell adhesion and support . Their density should be minimally above that of water (1 g/ml) so that they remain in suspension in a stirred tank (5). Instead of on a flat surface, cells are cultured on the surface of these microcarriers so that each particle carries several hundred cells, and therefore expansion capacity can be multiplied several times over. It provides a straightforward way to scale up culture systems for industrial production of cell or protein-based therapies, or for research purposes (5) (1). Furthermore, microcarriers can be used to deliver cells for targeted tissue engineering (1). Hepatocytes, chondrocytes, fibroblasts and more have been successfully delivered using biocompatible microcarriers to in vivo targets for the repair of damaged tissues (2). Microcarriers can also be used to deliver small molecules and proteins for the same purpose (2). --Great introduction, maybe it's a little too detailed, but other than that I don't see any major issues
 * In 1967, microcarrier development began when van Wezel found that the material could support the growth of anchorage-dependent cells. In particular, he used diethylaminoethyl–Sephadex microcarriers to aid in the culture and expansion of primary cells . The 1980s were marked with a wave of microcarrier development with the breakthrough of porous particles, which are able to support cell adhesion and protect them from outside forces better than solid microcarriers . --Can be its own subsection maybe under History if there is one?
 * Microcarrier cell culture is typically carried out in spinner flasks, although other vessels such as rotating wall microgravity bioreactors or fluidized bed bioreactors can also support microcarrier-based cultures. The vessels used in this culture must be treated to prevent cell adhesion to surfaces other than the microcarriers, such as with Sigmacote coating (4). ECM components such as collagen can also be used as an anti-adhesive coating on the culture vessels (3). --I feel like this can be in its own section

Examples of good feedback
A good article evaluation can take a number of forms. The most essential things are to clearly identify the biggest shortcomings, and provide specific guidance on how the article can be improved.


 * Peer review of "Homemaking"
 * Peer review of this article about a famous painting