S-S-PEG-COOH Self-Assembled Monolayer on Gold Surface Enabled a Combined Assay for Serological EBV Antibody Isotypes

A simplified direct on-chip forward or reverse immunoassay for evaluating protein-protein interactions in the serum

BACKGROUND

The identification of protein-protein interactions is a great challenge. In this study, we fabricated a gold surface-modified biochip with activated sophorolipids (SLs) in combination with 16-amino-1-hexadecanethiol hydrochloride to detect serum proteins.

MAIN METHODS AND MAJOR RESULTS

The on-chip immunoassay reported here included a forward assay, in which a ligand is immobilized on the biochip surface and allowed to interact with its free specific receptor in liquid phase, and a reverse assay, in which a receptor is loaded on the biochip surface and combined with its free specific ligand in solution. The specificity of the molecular interactions on the biochip was evaluated using immunological blocking assays and chemiluminescent immunoassays (CLIA). Hemophagocytic lymphohistiocytosis (HLH) serum was used to test the potential utilization of the biochip. Reverse receptor CD25-based interleukin (IL)-2 and forward ligand IL-2-based CD25 assays revealed that the limit of detection of the target proteins was as low as 156 and 78 pg/ml, respectively. Using receptor- or ligand-based platforms, we found that the positive rates of free IL-2 and soluble CD25 (sCD25) monomers in the sera of HLH patients were 14.3% and 71.4%, respectively. In addition, the biochip showed good compatibility with CLIA for the measurement of sCD25 (r = 0.77, p < 0.01).

CONCLUSIONS AND IMPLICATIONS

Biochip platforms, such as on-chip immunoprecipitation (IP), can be used to evaluate the interactions between proteins, ligands, and receptors, or enzymes and substrates in serum.

Primary small intestinal extranodal NK/T cell lymphoma, nasal type with kidney involvement: a rare case report and literature review

Background

Extranodal NK/T cell lymphoma, nasal type (EN-NK/T-NT) is a rare and aggressive type of non-Hodgkin’s lymphoma. EN-NK/T-NT seldom occurs in the gastrointestinal tract, and renal involvement is relatively rare.

Case presentation

Here we report a case of primary small intestinal EN-NK/T-NT with kidney involvement. We present the case of a 71-year-old female who was admitted to our hospital for coronary heart disease with a fever of unknown origin. Laboratory examination showed renal impairment and PET/CT showed a locally thickened wall of the small intestine, abnormally increased FDG metabolism in the right lower abdomen, and multiple slightly high-density masses with abnormal increased FDG metabolism in the right kidney. The gross specimen showed a grayish-white lump located in the ileum approximately 15 cm away from the ileocecum, and two grayish-white lumps located in the upper and lower poles of the right kidney, respectively. The pathological diagnosis was EN-NK/T-NT. The patient died approximately 10 months after the operation.

Conclusion

EN-NK/T-NT is a rare type of non-Hodgkin’s lymphoma and may develop insidiously, with fever as the only clinical manifestation. The disease was found to be difficult to diagnose in the early stage, resulting in a highly aggressive clinical course and short survival time.