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Purpose:Immune checkpoint inhibition (ICI) alone is not active in mismatch repair–proficient (MMR-P) metastatic colorectal cancer (mCRC), nor does radiotherapy alone result in objective systemic benefit. However, combined radiotherapy plus ICI can induce systemic antitumor immunity in preclinical and clinical models.Patients and Methods:In this single-center, phase II study, patients with chemotherapy-refractory MMR-P mCRC received durvalumab 1,500 mg plus tremelimumab 75 mg every 4 weeks plus radiotherapy. The primary endpoint was objective response rate (ORR) in nonirradiated lesions. Treatment and efficacy were correlated with peripheral immune cell profiles.Results:We enrolled 24 patients, and report outcomes after a median follow-up of 21.8 (range: 15.9–26.3) months. The ORR was 8.3% (2 patients) [95% confidence interval (CI), 1.0–27.0]. The median progression-free survival was 1.8 (95% CI, 1.7–1.9) months, median overall survival was 11.4 (95% CI, 10.1–17.4) months. Twenty five percent of patients (n = 6) had treatment-related grade 3–4 adverse events. We observed increased circulating CD8+ T lymphocyte activation, differentiation, and proliferation in patients with objective response.Conclusions:This combination of radiotherapy plus ICI study did not meet the prespecified endpoint criteria to be considered worthwhile for further study. However, rare instances of systemic immune augmentation and regression in nonirradiated lesions were observed (an abscopal response). Combination durvalumab and tremelimumab plus radiotherapy is feasible in MMR-P mCRC with a manageable safety profile. Further studies of novel immunotherapy combinations, and identification of biomarkers predictive of abscopal response are warranted.

Study design

Flow dot plots

Radiation treatment summary

Gene mutations in responder patients

Flow cytometry result summary

How immune dysregulation affects recovery from COVID-19 infection in patients with cancer remains unclear. We analyzed cellular and humoral immune responses in 103 patients with prior COVID-19 infection, more than 20% of whom had delayed viral clearance. Delayed clearance was associated with loss of antibodies to nucleocapsid and spike proteins with a compensatory increase in functional T cell responses. High-dimensional analysis of peripheral blood samples demonstrated increased CD8

Purpose:Immune checkpoint inhibition (ICI) alone is not active in mismatch repair–proficient (MMR-P) metastatic colorectal cancer (mCRC), nor does radiotherapy alone result in objective systemic benefit. However, combined radiotherapy plus ICI can induce systemic antitumor immunity in preclinical and clinical models.Patients and Methods:In this single-center, phase II study, patients with chemotherapy-refractory MMR-P mCRC received durvalumab 1,500 mg plus tremelimumab 75 mg every 4 weeks plus radiotherapy. The primary endpoint was objective response rate (ORR) in nonirradiated lesions. Treatment and efficacy were correlated with peripheral immune cell profiles.Results:We enrolled 24 patients, and report outcomes after a median follow-up of 21.8 (range: 15.9–26.3) months. The ORR was 8.3% (2 patients) [95% confidence interval (CI), 1.0–27.0]. The median progression-free survival was 1.8 (95% CI, 1.7–1.9) months, median overall survival was 11.4 (95% CI, 10.1–17.4) months. Twenty five percent of patients (n = 6) had treatment-related grade 3–4 adverse events. We observed increased circulating CD8+ T lymphocyte activation, differentiation, and proliferation in patients with objective response.Conclusions:This combination of radiotherapy plus ICI study did not meet the prespecified endpoint criteria to be considered worthwhile for further study. However, rare instances of systemic immune augmentation and regression in nonirradiated lesions were observed (an abscopal response). Combination durvalumab and tremelimumab plus radiotherapy is feasible in MMR-P mCRC with a manageable safety profile. Further studies of novel immunotherapy combinations, and identification of biomarkers predictive of abscopal response are warranted.

Fungi have a prominent status in fermentation for the production of different bio-products. Endophytic fungi isolated from medicinal plants are particularly formidable in their adaptability to solid state fermentation as an extension of its natural habitat and are also a potent source of broad-spectrum cellulolytic enzymes. We report for the first time the use of endophytic fungus isolated from Aegle marmelos for enhanced cellulolytic enzymes production from groundnut shell (GNS) as substrate. ImageJ software identified Trichoderma harzianum as an endophytic fungus having maximum radial growth rate. A systematic comparison of the endophytic fungus with Aspergillus oryzae , under solid state fermentation (SSF) and submerged fermentation (SmF) conditions was performed and enhanced cellulase production was observed by the endophytic fungus (4.27 FPU/ml) under SSF environment compared to SmF (2.35 FPU/ml). A comprehensive understanding of the systemic breakdown in the structural integrity of the biomass has been achieved using a synergy of enzyme assay protocols, spectral and thermal based techniques. The use of endophytic fungi in SSF systems in our study lays the basis for the production of other industrially important enzymes. The present study opens the door for the synergistic use of endophytic and epiphytic fungi for the production of cellulolytic enzyme.

The separation of particles and cells is critical in many chemical and biological applications. This work presents a simple idea for utilizing a pair of permanent magnets to continuously separate diamagnetic particles and cells in ferrofluid flow through a straight microchannel. The first magnet is placed close to the microchannel for focusing the particle mixture to a single stream without the use of a sheath flow. The second magnet, which is offset from the first magnet and placed farther from the channel, is to displace the aligned particles to dissimilar flow paths for a continuous sorting. This idea is first demonstrated through the separation of 3 μm- and 10 μm-diameter polystyrene particles, where the effects of flow speed and magnet distance are both examined. The experimental data are found to fit well with the predictions of an analytical model. Furthermore, a continuous separation of live yeast cells from 10 μm polystyrene particles is implemented in the same device.

Urinary tract infection (UTI) is a predominant condition in prostate cancer patients. Escherichia coli ORN178 (EC-178) is the uropathogen that causes recurrent infection by binding specifically to adhesins of prostate cancer cells (DU-145 cells). Gold nanoparticles (GNPs) have been used in biodiagnosis of pathogens. In this study, we have investigated the binding time of EC-178 to DU-145 cells, the cytotoxicity and uptake of plain and mannose functionalized and 20 and 200 nm GNPs (d-mannan (Mn)-GNPs). We also investigated the protein corona of GNPs when incubated with fetal bovine serum to study the protein corona which decides the biological fate of the GNPs. It was seen that EC-178 binds and is inside the DU-145 cells by 3 h of incubation period. Plain 20 nm GNPs decrease the percentage of viable cells in 48 and 72 h in log and lag phase of DU-145 cells. It was also observed that the Mn-GNPs were taken up by the DU-145 cells significantly more than the plain GNPs. Protein corona was observed when GNPs were incubated with fetal bovine serum which was confirmed by dynamic light scattering measurements and SDS-PAGE gel.

Concentrating particles to a detectable level is often necessary in many applications. Although magnetic force has long been used to enrich magnetic (or magnetically tagged) particles in suspensions, magnetic concentration of diamagnetic particles is relatively new and little reported. We demonstrate in this work a simple magnetic technique to concentrate polystyrene particles and live yeast cells in ferrofluid flow through a straight rectangular microchannel using negative magnetophoresis. The magnetic field gradient is created by two attracting permanent magnets that are placed on the top and bottom of the planar microfluidic device and held in position by their natural attractive force. The magnet–magnet distance is mainly controlled by the thickness of the device substrate and can be made small, allowing for the use of a dilute ferrofluid in the developed magnetic concentration technique. This advantage not only enables a magnetic/fluorescent label-free handling of diamagnetic particles, but also renders such handling biocompatible.

The binding of proteins to a nanostructure often alters protein secondary and tertiary structures. However, the main physical mechanisms that elicit protein conformational changes in the presence of the nanostructure have not yet been fully established. Here we performed a comprehensive spectroscopic study to probe the interactions between bovine serum albumin (BSA) and carbon-based nanostructures of graphene and single-walled carbon nanotubes (SWNTs). Our results showed that the BSA “corona” acted as a weak acceptor to facilitate charge transfer from the carbon nanostructures. Notably, we observed that charge transfer occurred only in the case of SWNTs but not in graphene, resulting from the sharp and discrete electronic density of states of the former. Furthermore, the relaxation of external α–helices in BSA secondary structure increased concomitantly with the charge transfer. These results may help guide controlled nanostructure-biomolecular interactions and prove beneficial for developing novel drug delivery systems, biomedical devices and engineering of safe nanomaterials.

A chemical free, nanotechnology-based, antimicrobial platform using Engineered Water Nanostructures (EWNS) was recently developed. EWNS have high surface charge, are loaded with reactive oxygen species (ROS) and can interact-with and inactivate an array of microorganisms, including foodborne pathogens. Here, it was demonstrated that their properties during synthesis can be fine tuned and optimized to further enhance their antimicrobial potential. A lab based EWNS platform was developed to enable fine-tuning of EWNS properties by modifying synthesis parameters. Characterization of EWNS properties (charge, size and ROS content) was performed using state-of-the art analytical methods. Further their microbial inactivation potential was evaluated with food related microorganisms such as Escherichia coli, Salmonella enterica, Listeria innocua, Mycobacterium parafortuitum and Saccharomyces cerevisiae inoculated onto the surface of organic grape tomatoes. The results presented here indicate that EWNS properties can be fine-tuned during synthesis resulting in a multifold increase of the inactivation efficacy. More specifically, the surface charge quadrupled and the ROS content increased. Microbial removal rates were microorganism dependent and ranged between 1.0 to 3.8 logs after 45 mins of exposure to an EWNS aerosol dose of 40,000 #/cm3.

The molecular basis of the diversity of fimbrial lectins dictates the extent of adhesion in different types of Escherichia coli strains to mammalian cells. The mechanism of receptor binding by E. coli in eukaryotic cells differs based on the adhesin domains, patterns in the macromolecular structure and the ligand-binding groove. Current sensor technologies utilize biosensors that are based on the carbohydrate moieties that are involved in pathogen adhesion to host cells. Nanoparticles have been extensively used as carriers for pathogen detection. Gold nanoparticles (Au NPs) of 200 nm size were functionalized with two distinct glycoconjugates mannose (Mn–Au NPs) and Neuαc(α2-3)-Gal-(β1-4)Glc–Paa (Sg–Au NPs) in order to investigate primary and fine sugar specificity of uropathogenic E. coli ORN178 and enterotoxigenic E. coli 13762, respectively. The UV-Vis measurement of pristine, 16-mercaptohexadecanoic acid (MHDA)/2-(2-aminoethoxy)ethanol (AEE)/sugar functionalized Au NPs showed a surface plasmon resonance band for Au. Dynamic light scattering analysis showed that the mean averages of the MHDA/AEE/Mn–Au NP samples increased due to aggregation. The negative zeta potentials of the samples were indicative of aggregation. Fine sugar specificity was observed when Neuαc(α2-3)-Gal-(β1-4)Glc–Paa functionalized Au NPs (Sg–Au NPs) specifically showed binding with E. coli 13762 but not with E. coli ORN178. This specificity of E. coli strains to identify and bind to characteristic sugar moieties can be used in the development of biodiagnostic tools with Au NPs as carriers for diagnosis/treatment of human and veterinary diseases. In regards to the growing antibiotic resistance of microorganisms, gold nanoparticles can also be functionalized specifically to reverse adhesion of E. coli to host tissue and can be detected by their optical properties.

Particle and cell separations are critical to chemical and biomedical analyses. This study demonstrates a continuous-flow electrokinetic separation of particles and cells in a serpentine microchannel through curvature-induced dielectrophoresis. The separation arises from the particle size-dependent cross-stream dielectrophoretic deflection that is generated by the inherent electric field gradients within channel turns. Through the use of a sheath flow to focus the particle mixture, we implement a continuous separation of 1 and 5 μm polystyrene particles in a serpentine microchannel under a 15 kV/m DC electric field. The effects of the applied DC voltages and the serpentine length on the separation performance are examined. The same channel is also demonstrated to separate yeast cells (range in diameter between 4 and 8 μm) from 3 μm particles under an electric field as low as 10 kV/m. The observed focusing and separation processes for particles and cells in the serpentine microchannel are reasonably predicted by a numerical model.

Separating live and dead cells is critical to the diagnosis of early stage diseases and to the efficacy test of drug screening, etc. This work demonstrates a novel microfluidic approach to dielectrophoretic separation of yeast cells by viability. It exploits the cell dielectrophoresis that is induced by the inherent electric field gradient at the reservoir-microchannel junction to selectively trap dead yeast cells and continuously separate them from live ones right inside the reservoir. This approach is therefore termed reservoir-based dielectrophoresis (rDEP). It has unique advantages as compared to existing dielectrophoretic approaches such as the occupation of zero channel space and the elimination of any mechanical or electrical parts inside microchannels. Such an rDEP cell sorter can be readily integrated with other components into lab-on-a-chip devices for applications to biomedical diagnostics and therapeutics.

Focusing particles and cells into a tight stream is often required in order for continuous flow detection, counting and sorting. So far a variety of particle focusing methods have been developed in microfluidic devices, among which magnetic focusing is still relatively new. We?develop in this work an approach to embedding symmetrically two repulsive permanent magnets about a straight rectangular microchannel in a PDMS-based microfluidic device. The closest distance between the magnets is limited only by the sizes of the embedded and holder magnets involved in the fabrication process. The developed device is used to implement and investigate the three-dimensional magnetic focusing of polystyrene particles in ferrofluid microflow with both the top- and side-view visualizations. The effects of flow speed and particle size on the particle focusing effectiveness are studied. The developed device is also applied to magnetically focus yeast cells in ferrofluid, which proves to be biocompatible as verified by a cell viability test. In addition, an analytical model is developed and found to be able to predict the experimentally observed particle and cell focusing behaviors with reasonable agreement.