ABSTRACT
BACKGROUND: Netherton syndrome (NS) is a severe autosomal recessive ichthyosis. It is characterized by congenital ichthyosiform erythroderma, trichorrhexis invaginata, ichthyosis linearis circumflexa, atopic diathesis, and frequent bacterial infections. The disease is caused by mutations in the SPINK5 (serine protease inhibitor Kazal-type 5) gene, a new type of serine protease inhibitor involved in the regulation of skin barrier formation and immunity. We report one Chinese adult with NS. The patient had typical manifestation of NS except for trichorrhexis invaginata with an atopic diathesis and recurrent staphylococcal infections since birth. AIMS: To evaluate the gene mutation and of its product activity of SPINK5 gene in confirmation of the diagnosis of one Chinese adult with NS. MATERIALS AND METHODS: To screen mutations in the SPINK5 gene, 33 exons and flanking intron boundaries of SPINK5 were amplified with polymerase chain reaction (PCR) and used for direct sequencing. In addition, immunohistochemical staining of LEKTI (lymphoepithelial Kazal-type-related inhibitor) with specific antibody was used to confirm the diagnosis of NS. The results were compared with that of healthy individuals (twenty-five blood samples). RESULTS: A G318A mutation was found at exon 5 of patient's SPINK5 gene which is a novel missense mutation. The PCR amplification products with mutation-specific primer were obtained only from the DNA of the patients and their mother, but not from their father and 25 healthy individuals. Immunohistochemical studies indicated there was no LEKTI expression in NS patient's skin and there was a strong LEKTI expression in the normal human skin. CONCLUSION: In this report, we describe heterozygous mutation in the SPINK5 gene and expression of LEKTI in one Chinese with NS. The results indicate that defective expression of LEKTI in the epidermis and mutations of SPINK5 gene are reliable for diagnostic feature of NS with atypical clinical symptoms.
ABSTRACT
<p><b>OBJECTIVES</b>To explore a sensitive and specific method for detection of bcl-2/IgH gene rearrangement in diffuse large B cell lymphoma (DLBCL), and verify the credibility of the established method.</p><p><b>METHODS</b>bcl-2/IgH hemi-nested PCR primers were designed using the professional primer design software. Fifty-two samples of pathologically diagnosed DLBCL and 10 fresh tonsil tissues were amplified using hemi-nested touch down-PCR to detect bcl-2/IgH gene rearrangement. The PCR products were cloned and sequenced.</p><p><b>RESULTS</b>bcl-2/IgH gene rearrangement was detected in 6 of 52 DLBCL samples and 2 of 10 fresh tonsil tissues using one-way method. By using the hemi-nested PCR for the second round amplification, 5 of DLBCL were positive, but all of the fresh tonsil tissues were negative. The positive PCR products were sequenced and analyzed on the Internet, 3 of 8 cases obtained by one-way method were false positive, 5 positive cases amplified using hemi-nested PCR were all bcl-2/IgH gene rearrangement. PCR products of 3 false positive cases were homologous to BAC331191 and LLNLR-245D11 in human chromosome 19 and RP11-498P10 in chromosome 1.</p><p><b>CONCLUSION</b>There are false positive results using common primers for detecting bcl-2/IgH gene rearrangement. The mechanism may be that highly homologous sequences to human genome exist in commonly used primers. The specificity of the diagnosis could be improved by hemi-nested PCR using the combination of primers we designed and the traditional ones.</p>
