Receptor clustering and activation by multivalent interaction through recognition peptides presented on exosomes

We demonstrate a novel system for inducing clustering of cell surface receptors via recognition peptide segments displayed on exosomes, leading to receptor activation. With this system, targeting of receptor-expressing cells and facilitation of the endocytic uptake of exosomes, which contained the anti-cancer protein saporin, were successfully achieved, leading to cell death.

Monocyte CD64 expression as a novel biomarker for the disease activity of systemic lupus erythematosus

Objective

Interferon alpha (IFN-α) is a key cytokine associated with systemic lupus erythematosus (SLE). IFN-α induces the expression of CD64 on monocytes (mCD64). Although enhanced mCD64 expression has been reported in patients with SLE, it has never been assessed quantitatively. The aim of this study was to investigate whether or not mCD64 expression correlates with SLE disease activity.

Methods

The mCD64 expression levels were assessed quantitatively in 40 patients with active or inactive SLE by using flow cytometry. The mCD64 expression levels were subsequently compared with the SLE disease activity index (SLEDAI) and levels of existing SLE activity biomarkers, such as anti-DNA antibody, complements, and so on.

Results

The mCD64 expression was significantly higher in active disease than in inactive disease SLE (median molecules/cell, interquartile range: 34,648, 8174–24,932 and 20,865, 6357–21,503, respectively; p < 0.001). The levels of mCD64 expression strongly correlated with SLEDAI ( r = 0.68, p < 0.001).

Conclusion

The mCD64 expression is a simple and useful biomarker for evaluating disease activity in patients with SLE.

Split-gate organic field-effect transistors for high-speed operation

Split-gate organic field-effect transistors have been developed for high-speed operation. Owing to the combination of reduced contact resistance and minimized parasitic capacitance, the devices have fast switching characteristics. The cutoff frequencies for the vacuum-evaporated devices and the solution-processed devices are 20 and 10 MHz, respectively. A speed of 10 MHz is the fastest device reported so far among solution-processed organic transistors.