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Peptidoglycan recognition proteins (PGRPs) are a class of pattern recognition receptors (PRRs) that activate the innate immune system in response to microbial infection by detection of peptidoglycan, a distinct component of bacterial cell walls. Bioinformatic studies have revealed four PGRPs in the red imported fire ant Solenopsis invicta; nonetheless, the mechanism of the immune response of S. invicta induced by pathogens is still poorly understood. The peptidoglycan recognition protein full-length cDNA (designated as SiPGRP-S1/S2/S3/L) from S. invicta was used in this investigation. According to the sequencing analysis, there was a significant degree of homology between the anticipated amino acid sequence of SiPGRPs and other members of the PGRPs superfamily. Molecular docking studies demonstrated that SiPGRPs show strong binding affinity for a variety of PGN substrates. Additionally, tissue distribution analysis indicated that SiPGRPs are primarily expressed in several tissues of naïve larvae, including fat body, hemocytes, head, and thorax, as detected by quantitative real-time PCR (RT-qPCR). Microbial challenges resulted in variable changes in mRNA levels across different tissues. Furthermore, the antibacterial effects of antimicrobial peptides (AMPs) produced by major ants infected with Metarhizium anisopliae were assessed. These AMPs demonstrated inhibitory effects against M. anisopliae, Staphylococcus aureus, and Escherichia coli, with the most pronounced effect observed against E. coli. In conclusion, SiPGRPs act as pattern recognition receptors (PRRs) that identify pathogens and initiate the expression of AMPs in S. invicta, this mechanism contributes to the development of biopesticides designed for the targeted control of invasive agricultural pests. [ABSTRACT FROM AUTHOR]

Rice planthoppers, including Nilaparvata lugens, Sogatella furcifera, and Laodelphax striatellus, are major agricultural pests. Serpins, which function as serine protease inhibitors, play a pivotal role in the immune systems of these insects, especially within the Toll signaling pathway and the prophenoloxidase (PPO) cascade. This study presents a comparative analysis of serpin genes among these species, highlighting their roles in immunity and development. Utilizing genomic and bioinformatics approaches, we identified 11, 11, and 14 serpin genes in N. lugens, S. furcifera, and L. striatellus, respectively. Phylogenetic analysis revealed a close evolutionary relationship between these serpin genes and Bombyx mori BmSerpins, emphasizing the functional diversity of the serpin family. Structural analysis confirmed the presence of the reactive center loop (RCL) in all serpin proteins, with the Serpin7 subfamily showing a unique dual RCL configuration. Expression profiling showed species-specific serpin expression patterns across different life stages and adult tissues. Moreover, transcriptional analysis of serpin genes in the three planthoppers following Metarhizium infection uncovered distinct immune regulatory patterns two days post-infection. Notably, the expression of NlSerpin2-2/6, SfSerpin4/6/7-1, and LsSerpin4/5-2/6 was upregulated post-infection, potentially enhancing antifungal capabilities. In contrast, the expressions of NlSerpin1/7-1/9 and LsSerpin1/2/3/8/13 were downregulated, possibly suppressing immune responses. Moreover, Serpin6s, which share a conserved phylogenetic lineage, exhibited enhanced immune activity in response to fungal invasion. These insights into serpin-mediated immune regulation could contribute to the development of novel pest-control strategies. [ABSTRACT FROM AUTHOR]

This study employs a regression discontinuity design to systematically examine the governance effect of bike-sharing on urban traffic congestion, utilizing city-level data from Beijing, Shanghai, and Wuhan in China between 2016 and 2018. We discover that the introduction of bike-sharing services significantly mitigates traffic congestion in the short term. Our heterogeneity analysis reveals that the initial deployment of shared bicycles primarily alleviates urban congestion, while additional deployments have a limited impact. Further, mechanism test analysis demonstrates that bike-sharing leads to increased metro ridership in these cities, effectively explaining the reduction in road congestion. This study underscores the pivotal role of bike-sharing services in easing urban traffic congestion and provides vital policy insights for enhancing traffic management strategies in Chinese cities. [ABSTRACT FROM AUTHOR]

Over the past century, the field of antibody discovery has undergone significant evolution, excluding the current exploration stage of artificial intelligence‐based antibody generation and the often overlooked non‐animal sourced antibody discovery, which typically requires mature in vitro affinity and the selection of high‐quality antigen formulations. This journey has traversed various stages, from methods involving serum‐based antibody acquisition, the isolation of B cells capable of perpetual antibody production through hybridoma technology, to the in‐depth exploration of genetic material using the phage display system, and the current stage involving diverse single B cell screening techniques. Additionally, the emergence of machine learning has brought impressive scientific and technological breakthroughs across research domains, proving to be a powerful application in the field of antibody discovery. However, each technique comes with its limitations, such as variability and control challenges in serum‐based acquisition, lengthy and difficult hybridoma‐derived antibody development, potential limitations in sequence and epitope diversity due to immunization biases in phage display techniques, and costly single B cell screening. Protein mass spectrometry sequencing, with shorter acquisition time and lower costs, is seen as a shortcut by diagnostic companies, impacting traditional antibody development. In diagnostic antibody development, methodological differences in downstream assays and the impact of constant regions outside the Fv core are often neglected. This paper deeply analyzes challenges, proposing innovative strategies for the next generation of diagnostic antibody development. Aimed at moving closer to the gold standard of antibody discovery, these strategies enhance the competitiveness of diagnostic reagent products. [ABSTRACT FROM AUTHOR]

PD-1/PD-L1 immune checkpoint therapy has become another important treatment for several refractory and recurrent tumors besides radiotherapy and chemotherapy; however, only some patients can benefit from it. PD-1/PD-L1 targeted radionuclide molecular probe imaging can detect the PD-1/PD-L1 expression in whole body including tumors and other tissues noninvasively, timely and repeatedly, which will be more convenient for screening the patients benefiting from the immune-therapy, the efficacy evaluation and dynamic monitoring of the changes of PD-1/PD-L1 expression during treatment, providing a strong basis for the adjustment of treatment plan. This paper will review the recent progress of PD-1/PD-L1 targeted molecular probes, in order to provide reference for clinical application and further research of tumor immunotherapy.

Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) is a highly dispersive, polyphagous insect pest that severely defoliates crops. Excessive reliance on synthetic insecticides leads to ecological pollution and resistance development, urging scientists to probe eco-friendly biopesticides. Here, we explore the virulence of an entomopathogenic fungus, Beauveria bassiana, against S. exigua, resulting in 88% larval mortality. Using an age–stage, two-sex life table, we evaluated the lethal and sublethal effects of B. bassiana on the demographic parameters of S. exigua, including survival, development, and reproduction. Sublethal (LC20) and lethal concentrations (LC50) of B. bassiana impacted the parental generation (F0), with these effects further influencing the demographic parameters of the first filial generation (F1). The infected F1 offsprings showed a reduced intrinsic rate of increase (r), mean generation time (T), and net reproduction rate (R0). Larval developmental duration varied significantly between the control (10.98 d) and treated groups (LC20: 10.42; LC50: 9.37 d). Adults in the treated groups had significantly reduced lifespans (M: 8.22; F: 7.32 d) than the control (M: 10.00; F: 8.22 d). Reduced fecundity was observed in the B. bassiana-infected groups (LC20: 313.45; LC50: 223.92 eggs/female) compared to the control (359.55 eggs/female). A biochemical assay revealed elevated levels of detoxification enzymes (esterases, glutathione S-transferases, and acetylcholinesterase) in the F0 generation after B. bassiana infection. However, the enzymatic activity remained non-significant in the F1 generation likely due to the lack of direct fungal exposure. Our findings highlight the enduring effects of B. bassiana on the biological parameters and population dynamics of S. exigua, stressing its use in eco-friendly management programs. [ABSTRACT FROM AUTHOR]

HER2 is not only a predictor of targeted therapy but also a definite prognostic factor. HER2-positive tumors are high-malignant, strong aggressive, with early metastasis and recurrence and poor prognosis. Therefore, accurate evaluation of HER2 status in cancer patients is the key to improve the efficacy, and it is crucial to clarify the HER2 status in vivo. However, HER2 status is highly heterogeneous during targeted therapy. The classical methods such as immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) cannot monitor the expression of HER2 in vivo, real time or dynamically and cannot accurately locate. It is difficult to meet the requirements of early diagnosis, treatment and precise treatment of malignant tumors with high HER2 expression. With the rapid development of molecular imaging, molecular probes could evaluate the effect of tumor immunotherapy quickly, accurately, noninvasively and effectively, and the probes play a critical role in solving the problem of tumor heterogeneity. Based on the existing HER2 molecular probes, this review analyzes the progress of molecular imaging-guided targeted therapy.

A single-domain antibody (sdAb) is the variable region extracted from antibodies with only heavy chains found in camelid serum. Single-domain antibodies have the characteristics of easy expression, good solubility, great stability and weak immunogenicity. Since single-domain antibodies have higher penetration in tissues than conventional antibodies and can be cleared by the kidneys quickly, they are ideally suited for various biotechnologies and clinical treatment of tumors. The monovalent sdAb could be coupled to radioisotopes, fluorescent dyes, biotin, magnetic beads, affinity matrices and so on. A complex molecular-conjugated sdAb can be used for in vivo multiple modes tumor imaging. In the basic research, development of probe and other fields, single-domain antibody has a broad prospect in application. This review summarizes the molecular features and the applications in tumor molecular imaging of single-domain antibodies.

Objective To investigate the application of 68Ga-PSMA-617 molecular probe for micro-PET imaging of gliomas tumor model. Methods DKFZ-PSMA-617, an effective prostate specific membrane antigen (PSMA) targeted probes, was chosen to be the precursor to be radiolabelled with 68Ga. The radio-chemical yield of 68Ga-PSMA-617 was analyzed by Radio-TLC. Cell uptake experiments were performed on PSMA (+) LNCaP, PSMA (-) PC-3 and U87MG cells. Nude mice bearing U87MG were injected with 68Ga-PSMA-617(7.4 MBq) via the tail vein. Micro-PET imaging was performed 5 and 40 min after the injection. Blocking studies were also performed in U87MG tumor-bearing mice after 40 min of co-injection of 68Ga-PSMA-617 with the PSMA inhibitor (S)-2-(3-((S)-1-carboxy-3-methylbutyl)ureido) pentanedioic acid (ZJ-43) (25 mg/kg). Results The radiotracer had a good radio-chemical yield of (99.0±1.9)% quickly tested by Radio-TLC. In cell uptake experiments, the specificity of 68Ga-PSMA-617 was confirmed in PSMA (+) LNCaP cells and PSMA (-) PC-3 cells; meanwhile, it proved the low expression level of PSMA in gliomas U87MG cell line. From micro-PET imaging, U87MG xenografts tumors were visualized and it showed good tumor-to-background value from 1.85±0.02 (5 min) to 3.62±0.175 (40 min) which could be blocked by ZJ-43. Conclusion 68Ga-PSMA-617 has the potential to be used not only in prostate cancer but also in gliomas tumor model.