Reviewer's report
Title:Murine CD4+CD25- cells activated in vitro with PMA/ionomycin and
anti-CD3 acquire regulatory function and ameliorate experimental colitis in vivo
Version: 1Date:18 October 2012
Reviewer: Marinos Kallikourdis
Reviewer's report:
In this manuscript Majowicz and coworkers elegantly show that CD4+CD25- T
cells activated in vitro via PMA/ionomycin express Treg-like markers and are able
to reduce the disease severity of experimental colitis.
The experimental methods are well-described and the experiments follow a
logical sequence and are thoroughly executed and reported. The in vivo
protective effect is studied from a variety of parameters and is convincing.
There is one issue with the interpretation of the results, which I outline below.
Discretionary Revisions:
The manuscript does not present data examining the in vitro suppressive
capacity of these cells. Whilst this could be considered not necessary, given the
convincing in vivo data, presenting in vitro suppression data could substantially
strengthen the conclusions drawn by the in vivo studies.
Minor Essential Revisions:
The number of CD45RBlow cells injected in “negative control” animals should be
stated.
Major Compulsory Revisions:
Experimental colitis, as performed by the authors and by many of the previous
reports cited, is induced by administration of 4*105 CD45RBhi T cells into a
lymphopenic recipient. Administration of an equal number of CD45RBLow cells
can protect from colitis, as indeed the authors and others have shown. However,
as shown in Barthlott, Kassiotis and Stockinger, J Exp Med (2003), injection of
increased numbers (6*106) of CD45RBhi cells, that have no suppressive
capacity, is sufficient to show a reduction in the severity of colitis, due to
“competition with neighboring T cells for limited resourses” that limits the
activation of the T cells in the lymphopenic host.
The authors used 1.2*106 TregPMA cells, which is appreciably less than the
number used by Barthlott and colleagues, though still 3 times more than the
number of CD45RBhi that cause the colitis. As a consequence, it is not possible
to exclude that at least part of the protective effect observed in vivo is not due to
the increased number of administered cells.
This caveat should be made clear in the discussion.
Dr M Kallikourdis
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests
Reviewer's report
Title:Murine CD4+CD25- cells activated in vitro with PMA/ionomycin and
anti-CD3 acquire regulatory function and ameliorate experimental colitis in vivo
Version: 1Date:18 October 2012
Reviewer: Marinos Kallikourdis
Reviewer's report:
In this manuscript Majowicz and coworkers elegantly show that CD4+CD25- T
cells activated in vitro via PMA/ionomycin express Treg-like markers and are able
to reduce the disease severity of experimental colitis.
The experimental methods are well-described and the experiments follow a
logical sequence and are thoroughly executed and reported. The in vivo
protective effect is studied from a variety of parameters and is convincing.
There is one issue with the interpretation of the results, which I outline below.
Discretionary Revisions:
The manuscript does not present data examining the in vitro suppressive
capacity of these cells. Whilst this could be considered not necessary, given the
convincing in vivo data, presenting in vitro suppression data could substantially
strengthen the conclusions drawn by the in vivo studies.
Minor Essential Revisions:
The number of CD45RBlow cells injected in “negative control” animals should be
stated.
Major Compulsory Revisions:
Experimental colitis, as performed by the authors and by many of the previous
reports cited, is induced by administration of 4*105 CD45RBhi T cells into a
lymphopenic recipient. Administration of an equal number of CD45RBLow cells
can protect from colitis, as indeed the authors and others have shown. However,
as shown in Barthlott, Kassiotis and Stockinger, J Exp Med (2003), injection of
increased numbers (6*106) of CD45RBhi cells, that have no suppressive
capacity, is sufficient to show a reduction in the severity of colitis, due to
“competition with neighboring T cells for limited resourses” that limits the
activation of the T cells in the lymphopenic host.
The authors used 1.2*106 TregPMA cells, which is appreciably less than the
number used by Barthlott and colleagues, though still 3 times more than the
number of CD45RBhi that cause the colitis. As a consequence, it is not possible
to exclude that at least part of the protective effect observed in vivo is not due to
the increased number of administered cells.
This caveat should be made clear in the discussion.
Dr M Kallikourdis
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests
Please review this paper.
user
Reviewer's report
Title:Murine CD4+CD25- cells activated in vitro with PMA/ionomycin and
anti-CD3 acquire regulatory function and ameliorate experimental colitis in vivo
Version: 1Date:18 October 2012
Reviewer: Marinos Kallikourdis
Reviewer's report:
In this manuscript Majowicz and coworkers elegantly show that CD4+CD25- T
cells activated in vitro via PMA/ionomycin express Treg-like markers and are able
to reduce the disease severity of experimental colitis.
The experimental methods are well-described and the experiments follow a
logical sequence and are thoroughly executed and reported. The in vivo
protective effect is studied from a variety of parameters and is convincing.
There is one issue with the interpretation of the results, which I outline below.
Discretionary Revisions:
The manuscript does not present data examining the in vitro suppressive
capacity of these cells. Whilst this could be considered not necessary, given the
convincing in vivo data, presenting in vitro suppression data could substantially
strengthen the conclusions drawn by the in vivo studies.
Minor Essential Revisions:
The number of CD45RBlow cells injected in “negative control” animals should be
stated.
Major Compulsory Revisions:
Experimental colitis, as performed by the authors and by many of the previous
reports cited, is induced by administration of 4*105 CD45RBhi T cells into a
lymphopenic recipient. Administration of an equal number of CD45RBLow cells
can protect from colitis, as indeed the authors and others have shown. However,
as shown in Barthlott, Kassiotis and Stockinger, J Exp Med (2003), injection of
increased numbers (6*106) of CD45RBhi cells, that have no suppressive
capacity, is sufficient to show a reduction in the severity of colitis, due to
“competition with neighboring T cells for limited resourses” that limits the
activation of the T cells in the lymphopenic host.
The authors used 1.2*106 TregPMA cells, which is appreciably less than the
number used by Barthlott and colleagues, though still 3 times more than the
number of CD45RBhi that cause the colitis. As a consequence, it is not possible
to exclude that at least part of the protective effect observed in vivo is not due to
the increased number of administered cells.
This caveat should be made clear in the discussion.
Dr M Kallikourdis
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests
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