Reviewer's report
Title:Assessment of leukemia inhibitory factor and glycoprotein 130 expression
in endometrium and uterine flushing: a possible diagnostic tool for impaired
fertility
Version: 3Date:15 July 2011
Reviewer: Evdokia Dimitriadis
Reviewer's report:
This is a descriptive paper and investigates the mRNA and protein levels of the
cytokine, leukemia inhibitory factor (LIF) and its signaling co-receptor, gp130 in
endometrium of normal fertile and subfertile women during the mid-secretory
phase of the menstrual cycle (the time when embryo implantation occurs). The
authors compare the levels of LIF and the soluble gp130 receptor in uterine
washings between the groups of women.
There are a number of studies that have investigated the levels of LIF in
endometrium and uterine washings of women with subfertility, while none have
previously examined the levels of soluble gp130 in uterine washings. This aspect
of the work is exciting as it may be useful as a non-invasive diagnostic as there is
currently no marker of women with endometrial related infertility.
Major revisions:
1. In the introduction, the authors can add more references. For example: A
reference for LIF expression in the fallopian tube and cervical mucus. Also,
references for LIF in uterine flushings.
2. Also, information on whether soluble gp130 competes antagonises LIF
signalling so that once LIF binds to soluble gp130 does it then inhibit downstream
LIF signalling. If this is the case it may be useful to look at the ration of
LIF:soluble gp130.
Material and methods:
3. Add more details on how the flushings were processed before storage. Were
any haemolysed?
How much fluid was recovered after flushing. Were the protein levels measured
in the washings? How do you standardize this between samples? Would
expressing the levels differ if you express the data per protein in washings or per
ml of washings?
Results:
4. RT-PCR is not quantitative so that you can only comment on whether the gene
is there or not. You can not comment on the mRNA levels detected.
Could label the Figure better.
Discussion.
5. ‘These results are not conflicting with the observation by Ledee-Bataille et
al., [19]who showed an inverse correlation between uterine flushing LIF
concentration and the likelihood of successful implantation. He might use
different
ELISA kit.’
I think that the above statement in the discussion suggests that it is critical to
perform a Western analysis on the tissues or washings to see what LIF forms the
ELISA may be measuring. I don’t think its plausable to state that the variability
between studies is due to different ELISA kits. What kits were used in the
studies? What forms of LIF do they measure? There may be other differences
between the studies.
6. ‘The issue that fertile women secreted higher soluble gp130 in uterine flushing
in presence of gp130 mRNA expression as low as in infertile women is not
conflicting because soluble gp130 can be produced also by proteolytic cleavage
of the membrane bound receptor’ This is confusing. Did the previous publication
show high or low soluble gp130 secreted from the endometrial biopsies in vitro
from women with infertility compared to fertile women? If so, how does this relate
to the present study where soluble gp130 was significantly decreased in the
infertile compared to fertile women?
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
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'