Effects of prophylactic use of sirolimus on bronchiolitis obliterans syndrome development in lung transplant recipients.

BACKGROUND: Sirolimus (SIR) has been shown to stabilize the lung function in lung transplant recipients with bronchiolitis obliterans syndrome (BOS). However, there is no long-term data on the prophylactic use of SIR in lung transplant recipients. This retrospective study examines the effects of SIR in the prevention of BOS. METHODS: From 1999 to 2009, 24 lung transplant recipients whose maintenance immunosuppression regimen consisted of tacrolimus (Tac), mycophenolate mofetil (MMF) or azathioprine (AZA), and prednisone (Pred), were switched to Tac, SIR, and Pred at 1 year after transplantation. From these 24 patients, 5 developed side effects that necessitated the cessation of SIR within 1 year, while 19 patients tolerated long-term use of SIR. The clinical outcomes of these 19 patients (SIR group) were compared with 22 lung transplant recipients whose immunosuppression regimen consisted of Tac, MMF or AZA, and Pred from the time of transplant (MMF group). Survival rates and freedom from BOS were calculated by the Kaplan-Meier method. RESULTS: The SIR group had a lower incidence of BOS and viral infection (p = 0.05), and higher survival rates (p = 0.004). The SIR group had lower levels of Tac and received less Pred. The incidences of acute rejection, carcinoma, hypertension, and diabetes were similar between both groups. CONCLUSIONS: Results from this study suggest that conversion to SIR 1 year after lung transplantation improves survival and decreases the development of BOS. Randomized studies with higher number of patients are needed to determine the prophylactic efficacy of sirolimus in preventing the development of BOS.

Spasmolytic polypeptide expressing metaplasia to preneoplasia in H. felis-infected mice.

BACKGROUND & AIMS: The emergence of oxyntic atrophy and metaplastic cell lineages in response to chronic Helicobacter pylori infection predisposes to gastric neoplasia. We have described a trefoil factor family 2 (TFF2; spasmolytic polypeptide) expressing metaplasia (SPEM) associated with gastric neoplasia in both rodent and human fundus. To examine the relationship of SPEM to the neoplastic process in the H. felis -infected C57BL/6 mouse, we have now studied the association of SPEM-related transcripts with preneoplasia. METHODS: SPEM-related transcripts were identified by microarray analysis of amplified cRNA from SPEM, and surface mucous cells were isolated by laser capture microdissection from the same gastric sections from male C57BL/6 mice infected with H. felis for 6 months. Expression of SPEM-related transcripts was assessed by in situ hybridization and quantitative RT-PCR, as well as immunohistochemistry for prothymosin alpha. RESULTS: Eleven SPEM-related transcripts were identified as detectable only in SPEM. The expression of the SPEM-related transcripts was validated by in situ hybridization and quantitative PCR. One transcript, the noncoding RNA Xist, was only identified in SPEM cells from the infected male mice. Ten of the 11 transcripts as well as TFF2 were also expressed in regions of gastritis cystica profunda. Immunocytochemistry for one of the identified proteins, prothymosin alpha, demonstrated prominent nuclear staining in SPEM and gastritis cystica profunda. CONCLUSIONS: The expression of SPEM-related transcripts in regions of gastritis cystica profunda suggests that SPEM represents a precursor lineage for the development of dysplasia in this animal model of gastric carcinogenesis.

Differential protein analysis of spasomolytic polypeptide expressing metaplasia using laser capture microdissection and two-dimensional difference gel electrophoresis.

Full analysis of cellular protein constituents is a valuable tool in the evaluation of tissues. Traditional methods of evaluation, however, are time-consuming and difficult to reproduce. Two-dimensional difference gel electrophoresis (2D-DIGE), a recently developed proteomic system, affords the ability to compare and evaluate protein extracts from multiple sources. Coupled with laser capture microdissection (LCM), this technology is a powerful tool in comparing the protein profiles of separate pure cell populations. Proteins are labeled in vitro with reactive cyanine dyes that fluoresce at differential wavelengths, and after comigration on two-dimensional gels, differing protein populations become apparent. The unique aspect of this technology is the ability to identify and quantify proteins from separate preparations without issues of gel-to-gel differences. These techniques coupled with the systems for robotic acquisition of specific spots on the gel, tryptic digestion, and MALDI mass spectrometry permit identification of proteins differentially expressed in two pure cell populations. The authors used these new technologies to analyze the protein constituents of spasmolytic polypeptide expressing metaplasia (SPEM), a gastric mucosal metaplasia (fundic antralization or pseudopyloric metaplasia) that develops in the atrophic fundus mucosa of mice infected with Helicobacter felis and in humans infected with Helicobacter pylori. In addition, SPEM has been identified in the atrophic mucosa surrounding a high percentage of gastric adenocarcinomas and may represent a precursor lineage of malignancy. This technology recognized 28 differentially expressed proteins between SPEM and surface cells. Identification of novel SPEM-related proteins would allow the development of new immunohistochemical antibodies to further study this important metaplasia.