Effects of platelets on characteristics of lymphocytes cultured in vitro and optimization of adoptive immunotherapy

T lymphocytes,the main participants of cellular immunity,can express a variety of surface molecules and form different lymphocyte subsets under the induction of different factors to play the functions of immune regulation and immune killing.Studies have shown that platelets play a crucial role in maintaining the stable differentiation of lymphocytes and the balance in immunomodulation.Therefore,it is necessary to study the effect of platelets on lymphocytes in vitro to better understand the role of platelets in the immune system and broaden the application of adoptive immunotherapy.Methods:Cell counting and microscopic observation were used to detect the effect of activated platelets on lymphocyte proliferation in vitro;Flow cytometry was used to detect whether changes in platelet activity affect the proportion of lymphocyte subpopulations in vitro,and to detect differences in the expression of granzyme B;lactate dehydrogenase assay(LDH)was used to determine the difference in lymphocyte killing activity caused by platelet activity in vitro.Results:This was the first to promote lymphocyte proliferation through the expression or release of certain molecules in vitro,demonstrating that platelet activation is one of the key factors.Secondly,activated platelets or inactivated platelets promoted lymphocyte subset differentiation by enhancing the proportion of CD3+CD8+T lymphocytes(CTL cells)but had a slight effect on the proportion of CD3+CD4+T(Th cells)and CD4+CD25+T lymphocytes(Treg cells).Then,it was found that either activated platelets or inactivated platelets down-regulated the proportion of natural killer(NK)T lymphocytes,while activated platelets significantly enhance the proportion of NK lymphocytes.Therefore,by further detecting the killing activity of PBMCs treated with platelets,it was found that activated platelets promoted the extensive anti-tumor activity of lymphocytes and significantly increased the expression of granzyme B.Conclusion:Our results suggest that activated platelets promote lymphocyte proliferation,optimize lymphocyte subpopulation ratio,and promote cytotoxic effect of lymphocytes in vitro,which may provide a new strategy for optimizing the adoptive immunotherapy culture system and improving its efficacy.

Highly efficient recognition of similar objects based on ionic robotic tactile sensors

Tactile sensing provides robots the ability of object recognition,fine operation,natural interaction,etc.However,in the actual scenario,robotic tactile recognition of similar objects still faces difficulties such as low efficiency and accuracy,resulting from a lack of high-performance sensors and intelligent recognition algorithms.In this paper,a flexible sensor combining a pyramidal microstructure with a gradient conformal ionic gel coating was demonstrated,exhibiting excellent signal-to-noise ratio(48 dB),low detection limit(1 Pa),high sensitivity(92.96 kPa^(-1)),fast response time(55 ms),and outstanding stability over 15,000 compression-release cycles.Furthermore,a Pressure-Slip Dual-Branch Convolutional Neural Network(PSNet)architecture was proposed to separately extract hardness and texture features and perform feature fusion.In tactile experiments on different kinds of leaves,a recognition rate of 97.16%was achieved,and surpassed that of human hands recognition(72.5%).These researches showed the great potential in a broad application in bionic robots,intelligent prostheses,and precise human–computer interaction.

Embedding variable micro-capacitors polydimethylsiloxane for enhancing output of triboelectric nanogenerator in power

Polydimethylsiloxane （PDMS） is an excellent material for investigating the mechanism of triboelectricity as it can easily be used to construct various microstructures. In this study, micro-capacitors （MCs） and variable microcapacitors （VMCs） were embedded in PDMS by filling PDMS with silver nanoparticles （NPs） and constructing an internal cellular structure. The output performance of the triboelectric nanogenerators （TENGs） based on MCs@PDMS and VMCs@PDMS films was systematically investigated, with variation of the filling content of silver NPs and the pore ratio and size. The microstructure, permittivity, dielectric loss, and capacitance of the VMCs@PDMS films were well characterized. The output current of the TENG based on the VMCs@PDMS film was respectively 4.0 and 1.6 times higher than that of the TENGs based on the pure PDMS film and MCs@PDMS film, and the output power density of the former reached 6 W·m-2. This study sheds light on the physical nature of conductive nanoparticle fillings and cellular structures in dielectric triboelectric polymers.

A facile strategy of in-situ anchoring of Co_(3)O_(4) on N doped carbon cloth for an ultrahigh electrochemical performance

Enhancement of supercapacitors(SCs)with high-energy density and high-power density is still a great challenge.In this paper,a facile strategy for in situ anchoring of Co_(3)O_(4) particles on N doped carbon cloth(pCoNCC)is reported.Due to the interaction of the doped N and Co_(3)O_(4),the electrochemical performance improves significantly,reaching 1,940.13 mF·cm^(−2) at 1 mA·cm^(−2) and energy density of 172.46μWh·cm^(−2) at the power density of 400μW·cm^(−2),much larger than that without N doping electrode of 28.5 mF·cm^(−2).An aqueous symmetric supercapacitor(ASSC)assembled by two pCoNCC electrodes achieves a maximum energy density of 447.42μWh·cm^(−2) and a highest power density of 8,000μW·cm^(−2).Utilizing such a high-energy storage ASSC,a digital watch and a temperature-humidity detector are powered for nearly 1 and 2 h,respectively.Moreover,the ASSC displays a superb electrochemical stability of 87.7%retention after 10,000 cycles at 40 mA·cm^(−2).This work would provide a new sight to enhance active materials performance and be beneficial for the future energy storage and supply systems.

Double-induced-mode integrated triboelectric nanogenerator based on spring steel to maximize space utilization

Integrated multilayered triboelectric nanogenerators （TENGs） are an efficient approach to solve the insufficient energy problem caused by a single-layered TENG for achieving high output power density. However, most integrated multilayered TENGs have a relatively large volume. Here, a double-induced-mode integrated triboelectric nanogenerator （DI-TENG） based on spring steel plates is presented as a cost-effective, simple, and high-performance device for ambient vibration energy harvesting. The unique stackable rhombus structure, in which spring steel plates act both as skeletons and as electrodes, can enhance the output performance and maximize space utilization. The DI-TENG with five repeated units in a volume of 12 cm × 5 cm × 0.4 cm can generate a short-circuit current of 51 μA and can transfer charges of 1.25 μC in a half period. The contrast experiment is conducted systematically and the results have proved that the DI-TENG has a great advantage over the single-induced-mode TENG （SI-TENG） with only one side of a friction layer on its electrode. Besides, the DI-TENG can easily power a commercial calculator and can be used as a door switch sensor.