Comparative expression profiling for human endoplasmic reticulum-resident aminopeptidases 1 and 2 in normal kidney versus distinct renal cell carcinoma subtypes

Altered expression of the ER-resident aminopeptidases ERAP1 and ERAP2 might play an important role in shaping the MHC class I-presented peptide repertoire, but their function in tumors has not been determined in detail. Thus, the expression of ERAP1, ERAP2 and HLA class I heavy chain (HC) was analysed in various renal tumor types and corresponding kidney parenchyma by immunohistochemistry. Additionally, comparative expression profilings of untreated versus interferon (IFN)-γ-treated RCC cell lines were performed applying qRT-PCR, Western blot and/or flow cytometry. Normal kidney tissues showed strong ERAP1 staining in the proximal tubules of 57.4 % of cases, in the distal tubules of 94.3 % of cases and in the medulla of 88.6 % of cases, whereas high ERAP2 levels were observed in the medulla of 77.1 % of cases and in both, proximal and distal tubules of about 88 % of cases. Imbalanced, downregulated and RCC subtype-specific ERAP1 or ERAP2 expression was detected in 12.7 % or 43.8 % of samples analyzed, respectively. A coordinated downregulation of ERAPs was found in 4.8 %, an upregulation of ERAP1 or ERAP2 in 22.8 % or 2.0 % of RCC lesions. No association exists between ERAP and HLA class I HC expression for any tissue type. A heterogeneous constitutive ERAP expression pattern was also detected in RCC cell lines with lower ERAP2 than ERAP1 expression levels, which was in 11/17 RCC cell lines inducible by IFN-γ. Conclusively, ERAP1 and ERAP2 might be involved in the development of immune escape mechanisms of RCC

Implementation of highly sophisticated flow cytometry assays in multi- center clinical studies: considerations and guidance

the item has no formal formal abstract as summary of the items the table of contents is given here: Table of contents 1 Introduction: 1.1 Technical overview and applications of flow cytometry 1.2 Use of flow cytometry for biomarker analysis in human clinical studies 2 Development and Validation of flow cytometry assays for clinical use 2.1 Summary of key challenges 2.2 Considerations for the Validation of PhosFlow assays used for PK/PD assessment 3 Whole blood flow cytometry assays in multi-center clinical studies: Immunophenotyping versus PhosFlow 3.1 On-site processing of whole blood samples 3.2 Stabilization of samples: stabilizing tubes or freezing of whole blood samples 3.3 Clinical study implementation 4 Summary and Future Perspectives