Sunday 20 May 2012

Solution to ScFv to refolding

sciseekclaimtoken-4fc237fa76b9c
sciseekclaimtoken-4fbd15cda804b


                                  
                    



<-----------------J. Biotech. 2011   (LEFT SIDE)                                                    

Sushma, K., Vijayalakshmi, M.A., Krishnan, V. & Satheeshkumar, P.K. (2011). Cloning, expression, purification and characterization of a single chain variable fragment specific to tumor necrosis factor alpha in Escherichia coli, Journal of Biotechnology, 156 (4) 244. DOI: 10.1016/j.jbiotec.2011.06.039


      J. Chrom B 2012 (RIGHT SIDE)      --------->                              

Sushma, K., Bilgimol, C.J., Vijayalakshmi, M.A. & Satheeshkumar, P.K. (2012). Recovery of active anti TNF-α ScFv through matrix-assisted refolding of bacterial inclusion bodies using CIM monolithic support, Journal of Chromatography B, 891-892 93. DOI: 10.1016/j.jchromb.2012.02.011




















      










----------------------------------------------------

This section 3.2 is from the J. Biotech. paper and is an illustration of the rising trend of omitting experimental data which would be relevant to the study.                            







                                                                                      

                                                                                        (J. Chrom B paper on the right)------>
 Should reviewers be OK with images of such quality?
  
 


J. Biotech paper (Figure 5)
 



----------------------------------------------------------------------------------------------------------
This paragraph is from the J. Biotech paper.  It appears that the ScFv from soluble fraction was less potent than Liu et al's anti-TNF alpha ScFv (already reported in 2007) and probably Geng et al's as well (?).

Why go for mutagenesis to bring something to a level that others have already shown or exceeded?  What are the advantages of E.coli over those expression systems used by Liu and Geng and their co-workers?

  ------------------------------------------------------------------------------------------------------------




                                                                                                        















                      


Notice that in spite of the very close similarity of the assays and the data, the J. Biotech paper's Fig. 6 legend above states that "control (untreated in figure) cells were without any TNF-alpha and anti-TNF-alpha ScFv treatment."  Does this mean that control cells got anti-TNF-alpha treatment and not TNF-alpha?  

J. Chrom B's Fig. 4's legend states that "control cells were without any treatment."  As the results are so similar, would this mean that the above wording actually means this "without any treatment"? 

The results themselves show that untreated cells serve as the control for 100% viability in this MTT assay because they (as the 2012 J. Chrom B paper states clearly) are completely untreated. 

Why then are there points all along the X axis in the form of diamonds in the J. Biotech paper and in the form of crosses in the J. Chrom B paper? 

What concentrations are these and of what?
-------------------------------------------------------------------------------------------------------------














Duplicate (redundant) publication – refers to repeated publication of a manuscript when there is clear overlap with 
a previous manuscript already published. Such overlap is possible when there is distinct similarity in the basic assumptions underlying the research, the sample characterization, identity of patients, research methods, research findings or conclusions.


Salami publication- refers to splitting the research findings from a single study and dispersing them in different publications or at different times, with the intended purpose of increasing the number of publications. (Israel Medical Association)
-----------------------------------------------------------------------------------------------------------
The following two papers cover the expression, purification and characterization of a single chain variable fragment (ScFv) specific to TNF alpha in E. coli: one deals with the soluble fraction (J. Biotech, 2011), the other solubilizes the insoluble fraction (J. Chrom B, 2012). 
Analysis of both papers will be presented side-by-side (if space permits) or the figure of the (later) J. Chrom B paper will follow that of the (earlier) J. Biotech. paper to allow comparison. 

Would the J. Chrom B paper qualify as a salami or a redundant or just a me-too paper?
-----------------------------------------------------------------------------------------------------------



J. Biotech. 2011     (LEFT SIDE)                                                     J. Chrom B 2012 (RIGHT SIDE)

Sushma, K., Vijayalakshmi, M.A., Krishnan, V. & Satheeshkumar, P.K. (2011). Cloning, expression, purification and characterization of a single chain variable fragment specific to tumor necrosis factor alpha in Escherichia coli, Journal of Biotechnology, 156 (4) 244. DOI: 10.1016/j.jbiotec.2011.06.039


                                                                                     

Sushma, K., Bilgimol, C.J., Vijayalakshmi, M.A. & Satheeshkumar, P.K. (2012). Recovery of active anti TNF-α ScFv through matrix-assisted refolding of bacterial inclusion bodies using CIM monolithic support, Journal of Chromatography B, 891-892 93. DOI: 10.1016/j.jchromb.2012.02.011










1 comment:

  1. Interesting! Antibody such as scfv helps us to kill the viruses and bacteria in our body. It's not too clear to me, I need to do more research about this. Thanks for sharing!

    ReplyDelete