Membrane dual-targeting probes:A promising strategy for fluorescence-guided prostate cancer surgery and lymph node metastases detection

Fluorescence-guided surgery(FGS)with tumor-targeted imaging agents,particularly those using the near-infrared wavelength,has emerged as a real-time technique to highlight the tumor location and margins during a surgical procedure.For accurate visualization of prostate cancer(PCa)boundary and lymphatic metastasis,we developed a new approach involving an efficient self-quenched near-infrared fluorescence probe,Cy-KUE-OA,with dual PCa-membrane affinity.Cy-KUE-OA specifically targeted the prostate-specific membrane antigen(PSMA),anchored into the phospholipids of the cell membrane of PCa cells and consequently showed a strong Cy7-de-quenching effect.This dual–membrane-targeting probe allowed us to detect PSMA-expressing PCa cells both in vitro and in vivo and enabled clear visualization of the tumor boundary during fluorescence-guided laparoscopic surgery in PCa mouse models.Furthermore,the high PCa preference of Cy-KUE-OA was confirmed on surgically resected patient specimens of healthy tissues,PCa,and lymph node metastases.Taken together,our results serve as a bridge between preclinical and clinical research in FGS of PCa and lay a solid foundation for further clinical research.

The establishment of polypeptide PSMA-targeted chimericantigen receptor-engineered natural killer cells forcastration-resistant prostate cancer and the induction of ferroptosis-related cell death

Background:The mortality of castration-resistant prostate cancer(CRPC)is high due to lack of an effective treatment.Chimeric antigen receptor(CAR)-based therapy is a promising immunotherapeutic strategy.Here,we aimed to design a novel CAR-natural killer(NK)cells with a clinically significant tumoricidal effect on CRPC.Methods:We constructed novel CAR-NK92MI cells with a CD244-based recombinant lentiviral vector.Different intracellular segments(CD244,NKG2D,or CD3ζ)were screened to identify the best candidate according to cell lysis assay and CD107a expression levels.To enhance the affinity of the CAR to the tumor antigen,we compared an antibody specific for prostate-specific membrane antigen(anti-PSMA)with PSMA-targeted polypeptide(p-PSMA),which was screened by phage display combinatorial library.Then,CAR-NK92MI cells with both a high affinity for PSMA and a strong tumoricidal capacity were generated.In addition,we verified their tumor-killing effect in vitro and in vivo.The release of cytokine by NK92MI cells was compared with that by CAR-NK92MI cells through flow cytometry and enzyme-linked immunosorbent assay.Moreover,ferroptosis-related cell death was explored as a possible underlying mechanism.Results:Three different CAR intracellular regions CAR1(CD244),CAR2(CD244,NKG2D)and CAR3(CD244,NKG2D,and CD3ζ)were constructed.CAR2 was chosen to confer a stronger tumoricidal ability on CAR-NK92MI cells.Compared with anti-PSMA,p-PSMA exhibited enhanced affinity for the tumor antigen.Thus,p-PSMA-CAR-NK92MI cells,which expressed CAR with a polypeptide-based antigen-binding region,an intracellular CD244 and a NKG2D costimulatory domain,were generated.They could selectively and successfully kill PSMA+target cells and exhibited specific lysis rate of 73.19%for PSMA-positive C4-2 cells and 33.04%for PSMA-negative PC3 cells.Additionally,p-PSMA-CAR-NK92MI cells had significantly higher concentrations of IFN-γ,TNF-αand granzyme B than NK92MI cells.In a CRPC cancer xenograft model,p-PSMA-CAR-NK92MI cells significantly inhibited tumor growth and exerted a more consistent killing effect than NK92MI cells.Moreover,ferroptosis is a potential mechanism through which CAR-NK92MI cells attack cancer cells,and is triggered by IFN-γ.Conclusions:p-PSMA-CAR-NK92MI cells can effectively kill CRPCPSMA+cells in vitro and in vivo.This strategy may provide additional treatment options for patients with CRPC.

Experimental study on the laminar flame speed of hydrogen/natural gas/air mixtures

Laminar flame speeds of hydrogen/natural gas/air mixtures have been measured over a full range of fuel compositions(0-100%volumetric fraction of H_(2))and a wide range of equivalence ratio using Bunsen burner.High sensitivity scientific CCD camera is use to capture the image of laminar flame.The reaction zone area is employed to calculate the laminar flame speed.The initial temperature and pressure of fuel air mixtures are 293 K and 1 atm.The laminar flame speeds of hydrogen/air mixture and natural gas/air mixture reach their maximum values 2.933 and 0.374 m/s when equivalence ratios equal to 1.7 and 1.1,respectively.The laminar flame speeds of hydrogen/natural gas/air mixtures rise with the increase of volumetric fraction of hydrogen.Moreover,the increase in laminar flame speed as the volumetric fraction of hydrogen increases presents an exponential increasing trend versus volumetric fraction of hydrogen.Empirical formulas to calculate the laminar flame speeds of hydrogen,natural gas,and hydrogen/natural gas mixtures are also given.Using these formulas,the laminar flame speed at different hydrogen fractions and equivalence ratios can be calculated.

Numerical study on laminar flame speed of natural gas-carbon monoxide-air mixtures

Laminar flame speeds of natural gas-carbon monoxide-air mixtures are calculated by CHEMKIN II with GRI Mech-3.0 over a large range of fuel compositions,equivalence ratios,and initial temperatures.The calculated results of natural gas are compared with previous experimental results that show a good agreement.The calculated laminar flame speeds of natural gas-carbon monoxide-air mixtures show a nonmonotonic increasing trend with volumetric fraction of carbon monoxide and an increasing trend with the increase of initial temperature of mixtures.The maximum laminar flame speed of certain fuel blend reaches its biggest value when there is 92%volumetric fraction of carbon monoxide in fuel at different initial temperatures.Five stoichiometric natural gas-carbon monoxide-air mixtures are selected to study the detailed chemical structure of natural gas-carbon monoxide-air mixtures.The results show that at stoichiometric condition,the fuel blend with 80%volumetric fraction of carbon monoxide has the biggest laminar flame speed,and the C normalized total production rate of methane with 80%volumetric fraction of carbon monoxide is the largest of the five stoichiometric mixtures.

Experimental investigations on combustion characteristics of syngas composed of CH_(4),CO,and H_(2)

The residual gas and remained raw gas in dual gas resources polygeneration system are quite complex in components(mainly CH_(4),CO,and H_(2)),and these results to the distinguished differences in combustion reaction.Experimental investigations on basic combustion characteristics of syngas referred above are conducted on a laboratory-scale combustor with flame temperature and flue gas composition measured and analyzed.Primary air coefficient(PA),total air coefficient(TA),and components of the syngas(CS)are selected as key factors,and it is found that PA dominates mostly the ignition of syngas and NOx formation,while TA affects the flue gas temperature after high temperature region and NOx formation trend to be positive as H_(2)/CO components increase.The results provide references for industrial utilization.