Correspondence

Molecular Heterogeneity in Acute Renal Allograft Rejection and DNA Microarrays

N Engl J Med 2003; 349:2269December 4, 2003

Article

To the Editor:

The results of the study by Sarwal et al. (July 10 issue)1 are very encouraging for those interested in the underlying pathogenesis of organ rejection, as well as those seeking new laboratory-based diagnostic methods for application to clinical practice. Perhaps the only question concerns the interval between biopsy and the freezing of tissue, which is not stated. Concern has been expressed about the possibility of artifactually induced gene expression in DNA microarray studies, particularly if there is a delay before the tissue is frozen and the tissue is left at room temperature for some time.2 It is possible that hypoxia after the excision of tissue could lead to altered gene-expression profiles.3,4 Several of the genes implicated in this scenario encode transcription factors that could further affect the expression of other genes. This artifactual induction of gene expression may be a hypothetical issue in the current study, but it is certainly one that should be considered in any DNA microarray analysis.4

Paul K. Wright, M.B., Ch.B.
Cameron Raine, M.B., Ch.B.
University Hospital of North Durham, Durham DH1 5TW, United Kingdom

4 References

1. 1

   Sarwal M, Chua M-S, Kambham N, et al. Molecular heterogeneity in acute renal allograft rejection identified by DNA microarray profiling. N Engl J Med 2003;349:125-138
   Full Text | Web of Science | Medline

2. 2

   Zeller R. In situ hybridisation and immunohistochemistry. In: Ausbel FM, Brent R, Kingston RE, et. al., eds. Current protocols in molecular biology. New York: John Wiley, 2001:14.1.1-14.14.8.
   

3. 3

   Wang GL, Semenza GL. General involvement of hypoxia-inducible factor 1 in transcriptional response to hypoxia. Proc Natl Acad Sci U S A 1993;90:4304-4308
   CrossRef | Web of Science | Medline

4. 4

   Wenger RH, Rolfs A, Marti HH, Bauer C, Gassmann M. Hypoxia, a novel inducer of acute phase gene expression in a human hepatoma cell line. J Biol Chem 1995;270:27865-27870
   CrossRef | Web of Science | Medline

Citing Articles (2)

Citing Articles

1. 1

   Paolo Cravedi, Roslyn B Mannon. (2009) Noninvasive methods to assess the risk of kidney transplant rejection. Expert Review of Clinical Immunology 5:5, 535-546
   CrossRef

2. 2

   M. Sara Rosenthal, Heather Hanson Pierce. (2005) Inherited Medullary Thyroid Cancer and the Duty to Warn: Revisiting Pate v. Threlkel in Light of HIPAA. Thyroid 15:2, 140-145
   CrossRef