The Application of Organoids in the Study of Antiviral Innate Immunity.

Antiviral innate immunity plays a critical role in the defense against viral infections, yet its complex interactions with viruses have been challenging to study using traditional models. Organoids, three-dimensional (3D) tissue-like structures derived from stem cells, have emerged as powerful tools for modeling human tissues and studying the complex interactions between viruses and the host innate immune system. This chapter summarizes relevant applications of organoids in antiviral innate immunity studies and provides detailed information and experimental procedures for using organoids to study antiviral innate immunity.

Zebrafish as a Model for Investigating Antiviral Innate Immunity.

Zebrafish is a widely used model organism in genetics, developmental biology, pathology, and immunology research. Due to their fast reproduction, large numbers, transparent early embryos, and high genetic conservation with the human genome, zebrafish have been used as a model for studying human and fish viral diseases. In particular, the ability to easily perform forward and reverse genetics and lacking a functional adaptive immune response during the early period of development establish the zebrafish as a favored option to assess the functional implication of specific genes in the antiviral innate immune response and the pathogenesis of viral diseases. In this chapter, we detail protocols for the antiviral innate immunity analysis using the zebrafish model, including the generation of gene-overexpression zebrafish, generation of gene-knockout zebrafish by clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology, methods of viral infection in zebrafish larvae, analyzing the expression of antiviral genes in zebrafish larvae using qRT-PCR, Western blotting and transcriptome sequencing, and in vivo antiviral assays. These experimental protocols provide effective references for studying the antiviral immune response in the zebrafish model.

In Vitro and In Vivo Evaluation of Virus-Induced Innate Immunity in Mouse.

The innate immune system is the first line of host defense against infection by pathogenic microorganisms, among which macrophages are important innate immune cells. Macrophages are widely distributed throughout the body and recognize and eliminate viruses through pattern recognition receptors (PRRs) to sense pathogen-associated molecular patterns (PAMPs). In the present chapter, we provide detailed protocols for vesicular stomatitis virus (VSV) amplification, VSV titer detection, isolation of mouse primary peritoneal macrophages, in vitro and in vivo VSV infection, detection of interferon-beta (IFN-ß) expression, and lung injury. These protocols provide efficient and typical methods to evaluate virus-induced innate immunity in vitro and in vivo.

Pulmonary delivery of silver nanoparticles prevents influenza infection by recruiting and activating lymphoid cells.

Silver nanoparticles (AgNPs) are a potential antiviral agent due to their ability to disrupt the viral particle or alter the virus metabolism inside the host cell. In vitro, AgNPs exhibit antiviral activity against the most common human respiratory viruses. However, their capacity to modulate immune responses during respiratory viral infections has yet to be explored. This study demonstrates that administering AgNPs directly into the lungs prior to infection can reduce viral loads and therefore virus-induced cytokines in mice infected with influenza virus or murine pneumonia virus. The prophylactic effect was diminished in mice with depleted lymphoid cells. We showed that AgNPs-treatment resulted in the recruitment and activation of lymphocytes in the lungs, particularly natural killer (NK) cells. Mechanistically, AgNPs enhanced the ability of alveolar macrophages to promote both NK cell migration and IFN-γ production. By contrast, following infection, in mice treated with AgNPs, NK cells exhibited decreased activation, indicating that these nanoparticles can regulate the potentially deleterious activation of these cells. Overall, the data suggest that AgNPs may possess prophylactic antiviral properties by recruiting and controlling the activation of lymphoid cells through interaction with alveolar macrophages.

Establishment of a rapid detection method for Mycoplasma pneumoniae based on RPA-CRISPR-Cas12a technology.

Mycoplasma pneumoniae can cause respiratory infections and pneumonia, posing a serious threat to the health of children and adolescents. Early diagnosis of Mycoplasma pneumoniae infection is crucial for clinical treatment. Currently, diagnostic methods for Mycoplasma pneumoniae infection include pathogen detection, molecular biology techniques, and bacterial culture, all of which have certain limitations. Here, we developed a rapid, simple, and accurate detection method for Mycoplasma pneumoniae that does not rely on large equipment or complex operations. This technology combines the CRISPR-Cas12a system with recombinase polymerase amplification (RPA), allowing the detection results to be observed through fluorescence curves and immunochromatographic lateral flow strips.It has been validated that RPA-CRISPR/Cas12a fluorescence analysis and RPA-CRISPR/Cas12-immunochromatographic exhibit no cross-reactivity with other common pathogens, and The established detection limit was ascertained to be as low as 102 copies/µL.Additionally, 49 clinical samples were tested and compared with fluorescence quantitative polymerase chain reaction, demonstrating a sensitivity and specificity of 100%. This platform exhibits promising clinical performance and holds significant potential for clinical application, particularly in settings with limited resources, such as clinical care points or resource-constrained areas.

Engineering mesoporous polydopamine-based potentiate STING pathway activation for advanced anti-biofilm therapy.

The biofilm-induced "relatively immune-compromised zone" creates an immunosuppressive microenvironment that is a significant contributor to refractory infections in orthopedic endophytes. Consequently, the manipulation of immune cells to co-inhibit or co-activate signaling represents a crucial strategy for the management of biofilm. This study reports the incorporation of Mn2+ into mesoporous dopamine nanoparticles (Mnp) containing the stimulator of interferon genes (STING) pathway activator cGAMP (Mncp), and outer wrapping by M1-like macrophage cell membrane (m-Mncp). The cell membrane enhances the material's targeting ability for biofilm, allowing it to accumulate locally at the infectious focus. Furthermore, m-Mncp mechanically disrupts the biofilm through photothermal therapy and induces antigen exposure through photodynamic therapy-generated reactive oxygen species (ROS). Importantly, the modulation of immunosuppression and immune activation results in the augmentation of antigen-presenting cells (APCs) and the commencement of antigen presentation, thereby inducing biofilm-specific humoral immunity and memory responses. Additionally, this approach effectively suppresses the activation of myeloid-derived suppressor cells (MDSCs) while simultaneously boosting the activity of T cells. Our study showcases the efficacy of utilizing m-Mncp immunotherapy in conjunction with photothermal and photodynamic therapy to effectively mitigate residual and recurrent infections following the extraction of infected implants. As such, this research presents a viable alternative to traditional antibiotic treatments for biofilm that are challenging to manage.

Attenuation of Torque teno viral load over time in kidney transplantation recipients treated with calcineurin inhibitors is mitigated after conversion to belatacept.

Torque Teno Virus (TTV) is a non-pathogenic anellovirus, highly prevalent in healthy populations. Variations in its viral load have been associated with states of diminished immunity, as occurs after organ transplantation. It is hypothesized that TTV-load might be used as a diagnostic tool to guide prescription and dosing of immunosuppressive drugs. Not much is known about the effects of combined immunosuppressive drugs on TTV replication in renal transplantation. Belatacept was introduced to counter side-effects of calcineurin inhibitors (CNI). It was never widely adopted, mainly because its association with increased risk of rejection. To investigate the differential effects of a regimen based on calcineurin inhibitors versus belatacept on TTV-loads, we measured TTV-levels in 105 patients from two randomized controlled trials in kidney transplant recipients (KTRs). We observed that time after transplantation was inversely related to TTV-levels of patients that remained on a CNI-containing regime, whereas this decline over time was diminished after conversion to belatacept. In addition, a correlation with tacrolimus-trough levels and age were found. Our study is the first report on the impact of conversion from CNI to belatacept on TTV-levels in KTR. In conclusion, the time-related decline in TTV-levels is mitigated after conversion from CNI to belatacept.

An unusual case of Herbaspirillum huttiense bacteraemia in a haemodialysis patient.

Herbaspirillum spp. is a common environmental bacterium usually found in soil, plant roots, and water. It is rarely associated with infection in immunocompromised patients, and rarely reported infections in immunocompetent patients. We report the first case of a Herbaspirillum huttiense bacteraemia in a non-neutropenic home haemodialysis patient. A 57-year-old male presented to our hospital with a 3-day history of malaise, fevers, rigours, and anorexia following dialysis through his central line. On examination, he was pyrexic (temperature 38.7°C) with splinter haemorrhages noted, but no other signs of infection were present. Blood cultures revealed a polymicrobial infection, with Serratia liquefaciens and Corynebacterium jeikeium isolated from the central line and Herbaspirillum sp. was isolated from both the central line and a peripheral culture. A later peripheral blood culture following central line removal isolated Herbaspirillum huttiense. Regular biological testing of his home water supply and dialysate detected no colony forming units of non-fermenting gram-negative bacilli. He was initially treated with ceftriaxone and vancomycin initially, followed by ertapenem and vancomycin. Intravenous antibiotics were ceased following 5 days after central line removal and he made an uneventful recovery.

Metabolic homeostasis in fungal infections from the perspective of pathogens, immune cells, and whole-body systems.

SUMMARYThe ability to overcome metabolic stress is a major determinant of outcomes during infections. Pathogens face nutrient and oxygen deprivation in host niches and during their encounter with immune cells. Immune cells require metabolic adaptations for producing antimicrobial compounds and mounting antifungal inflammation. Infection also triggers systemic changes in organ metabolism and energy expenditure that range from an enhanced metabolism to produce energy for a robust immune response to reduced metabolism as infection progresses, which coincides with immune and organ dysfunction. Competition for energy and nutrients between hosts and pathogens means that successful survival and recovery from an infection require a balance between elimination of the pathogen by the immune systems (resistance), and doing so with minimal damage to host tissues and organs (tolerance). Here, we discuss our current knowledge of pathogen, immune cell and systemic metabolism in fungal infections, and the impact of metabolic disorders, such as obesity and diabetes. We put forward the idea that, while our knowledge of the use of metabolic regulation for fungal proliferation and antifungal immune responses (i.e., resistance) has been growing over the years, we also need to study the metabolic mechanisms that control tolerance of fungal pathogens. A comprehensive understanding of how to balance resistance and tolerance by metabolic interventions may provide insights into therapeutic strategies that could be used adjunctly with antifungal drugs to improve patient outcomes.

The dual role of ribosomal protein SA in pathogen infection: the key role of structure and localization.

Ribosomal protein SA (RPSA) plays multiple roles in cells, including ribosomal biogenesis and translation, cellular migration, and cytoskeleton reorganization. RPSA is crucial in the process of pathogen infection. Extensive research has examined RPSA's role in pathogen adhesion and invasion, but its broader functions, particularly its anti-infective capabilities, have garnered increasing attention in recent years. This dual role is closely related to its structural domains, which influence its localization and function. This review summarizes key research findings concerning the functional domains of RPSA and analyzes the relationship between its membrane localization and structural domains. Additionally, the functional implications of RPSA are categorized based on its different localizations during pathogen infection. Specifically, when RPSA is located on the cell surface, it promotes pathogen adhesion and invasion of host cells; conversely, when RPSA is located intracellularly, it exhibits anti-infective properties. Overall, RPSA shows a dual nature, both in facilitating pathogen invasion of the host and in possessing the ability to resist pathogen infection. This review comprehensively examines the dual role of RPSA in pathogen infection by analyzing its structural domains, localization, and interactions with cellular and pathogen molecules. Our aim is to update and deepen researchers' understanding of the various functions of RPSA during pathogen infection.

Organic-Inorganic Interfacial Dipole Induced by Energy Level Alignment for Efficient Photocatalytic Sterilization.

Photocatalytic molecules are considered to be one of the most promising substitutions of antibiotics against multidrug-resistant bacterial infections. However, the strong excitonic effect greatly restricts their efficiency in antibacterial performance. Inspired by the interfacial dipole effect, a Ti3C2 MXene modified photocatalytic molecule (MTTTPyB) is designed and synthesized to enhance the yield of photogenerated carriers under light irradiation. The alignment of the energy level between Ti3C2 and MTTTPyB results in the formation of an interfacial dipole, which can provide an impetus for the separation of carriers. Under the role of a dipole electric field, these photogenerated electrons can rapidly migrate to the side of Ti3C2 for improving the separation efficiency of photogenerated electrons and holes. Thus, more electrons can be utilized to produce reactive oxygen species (ROS) under light irradiation. As a result, over 97.04% killing efficiency can be reached for Staphylococcus aureus (S. aureus) when the concentration of MTTTPyB/Ti3C2 was 50 ppm under 660 nm irradiation for 15 min. A microneedle (MN) patch made from MTTTPyB/Ti3C2 was used to treat the subcutaneous bacterial infection. This design of an organic-inorganic interface provides an effective method to minimize the excitonic effect of molecules, further expanding the platform of inorganic/organic hybrid materials for efficient phototherapy.

Feasibility Testing of the Bionet Sonar Ultrasound Transcutaneous Energy Transmission (UTET) System for Wireless Power and Communication of a LVAD.

PURPOSE: To address the clinical need for totally implantable mechanical circulatory support devices, Bionet Sonar is developing a novel Ultrasonic Transcutaneous Energy Transmission (UTET) system that is designed to eliminate external power and/or data communication drivelines. METHODS: UTET systems were designed, fabricated, and pre-clinically tested using a non-clinical HeartWare HVAD in static and dynamic mock flow loop and acute animal models over a range of pump speeds (1800, 2400, 3000 RPM) and tissue analogue thicknesses (5, 10, 15 mm). RESULTS: The prototypes demonstrated feasibility as evidenced by meeting/exceeding function, operation, and performance metrics with no system failures, including achieving receiver (harvested) power exceeding HVAD power requirements and data communication rates of 10kB/s and pump speed control (> 95% sensitivity and specificity) for all experimental test conditions, and within healthy tissue temperature range with no acute tissue damage. CONCLUSION: During early-stage development and testing, engineering challenges for UTET size reduction and stable and safe operation were identified, with solutions and plans to address the limitations in future design iterations also presented.

Mycoplasma hominis as Cause of Extragenital Infection in Patients with Hypogammaglobulinemia: Report of 2 Cases and Literature Review.

Mycoplasma hominis can be a part of human urogenital tract microbiome, and it is a frequent cause of urogenital infections. In rare cases, it can also cause extragenital infections, especially in immunocompromised patients. In this case series, we report two cases and provide a literature review of extragenital infections caused by M. hominis in patients with hypogammaglobulinemia. Patient 1 was a 61-year-old woman with diffuse large B-cell lymphoma who, after rituximab-containing chemotherapy and CAR-T therapy, developed M. hominis spondylodiscitis. Patient 2 was a 50-year-old woman with congenital hypogammaglobulinemia who developed disseminated M. hominis infection involving pleura, muscles, and right ankle. Antibiotic therapy with levofloxacin and doxycycline for 10 weeks in patient 1 and with levofloxacin alone for 6 weeks in patient 2 led to infection resolution. The literature review identified 14 additional cases reporting M. hominis extragenital infection in patients with hypogammaglobulinemia. M. hominis should also be suspected as an etiological agent of extragenital infection in patients with B-cell immunodeficiency with a clinical picture of persistent, standard-culture negative infection, particularly with arthritis or abscess formation. Even if M. hominis can grow on standard bacterial medium, in suspected cases molecular methods should be promptly used for correct diagnostic work-up and successful therapy.

Pufferfish gasdermin Ea is a significant player in the defense against bacterial pathogens.

Gasdermins (GSDMs) are proteins cleaved by caspase (CASP) to trigger pyroptosis. In teleosts, pyroptosis is mediated by gasdermin E (GSDME). The Pufferfish, Takifugu rubripes, possesses two GSDME orthologs: named TrGSDMEa and TrGSDMEb. TrGSDMEa is cleaved by CASP3/7 to liberate the N-terminal (NT) domain that can trigger pyroptosis in mammalian cells. However, the biological function of TrGSDMEa in pufferfish is unknown, and TrGSDMEb is poorly studied. We found that TrGSDMEb was cleaved by CASP1/3/6/7/8, but the resulting NT domain, despite its similarity to TrGSDMEa-NT domain in sequence and structure, failed to induce pyroptosis. TrGSDMEa and TrGSDMEb exhibited similar expression patterns in pufferfish under normal physiological conditions but were up- and downregulated, respectively, in expression during Vibrio harveyi and Edwardsiella tarda infection. Bacterial infection induced the activation of TrGSDMEa and CASP3/7 in pufferfish cells, resulting in pyroptosis accompanied with IL-1ß production and maturation. Inhibition of TrGSDMEa-mediated pyroptosis via TrCASP3/7 reduced the death of pufferfish cells and augmented bacterial dissemination in fish tissues. Structure-oriented mutagenesis identified 16 conserved residues in teleost GSDMEa that were required for the pore formation or auto-inhibition of GSDMEa. This study illustrates the role of GSDMEa-mediated pyroptosis in teleost defense against bacterial pathogens and provides new insights into the structure-based function of vertebrate GSDME. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-024-00237-x.

Salmonella in the food chain within the Gulf Cooperation Council countries.

Infections caused by bacteria originating from tainted food sources are a widespread concern due to their large economic impact and detrimental effects on public health. We aimed to explore literature focusing on the presence of Salmonella in the food supply chains of Gulf Cooperation Council (GCC) countries and to provide an overview of available information concerning health-related issues and the status of salmonellosis in humans in GCC countries. The reviewed evidence underscored a gap in our comprehensive understanding of the prevalence of Salmonella in the food supply of GCC countries. Molecular characterization efforts to pinpoint the sources of Salmonella in these nations were limited. Surveys targeting Salmonella in the food supply of GCC countries have been infrequent. While qualitative data indicated the presence or absence of Salmonella, there was a noticeable lack of quantitative data detailing the actual quantities of these bacteria in chicken meat supplies across GCC countries. Although reports regarding Salmonella in animal-derived foods were common, the literature highlighted in this review emphasized the persistent challenge that Salmonella pose to food safety and public health in GCC countries. Addressing this issue requires concerted efforts to enhance surveillance, improve control measures, and promote greater awareness among stakeholders in the food supply chain.

Case report: Thoracic vertebral abscess caused by Salmonella via diagnosed next-generation sequencing.

The genus Salmonella consists of Gram-negative bacteria with various serotypes. It commonly causes bacterial infections that affect the intestines. Infection can occur in humans and animals through the ingestion of contaminated food or water, or through contact with infected animals or environments. Complications commonly include intestinal hemorrhage and perforation, though vertebral osteomyelitis is rarely observed. Therefore, in patients with spinal cord abscesses, The genus Salmonella is typically not considered a likely pathogen, especially in the absence of typical symptoms. In this case, the limited information provided by traditional cultivation methods, particularly under the influence of antibiotics. However, next-generation sequencing (NGS) unexpectedly detected Salmonella, which assisted in formulating the final treatment plan. This underscores the role and clinical value of NGS in pathogen identification.

Aortoenteric Fistula with Digestive Contrast Material Leaking in the Aneurysmal Sac.

Teaching point: Aortoenteric fistula, a major complication of aortic surgery, can be identified with certainty on CT scan with opacification of the intestinal tract.

Correlation Between ABO Blood Grouping and Erythrocyte Sedimentation Rate (ESR) in Periodontal Diseases.

This study investigates the relationship between erythrocyte sedimentation rate (ESR) and ABO blood grouping in the context of periodontal disorders. Periodontal diseases, chronic inflammatory conditions that damage the tissues supporting teeth, can lead to tooth loss if left untreated. ESR, a common hematological test indicating systemic inflammation, has been linked to the severity of periodontal disease. ABO blood grouping, a hereditary trait, is linked to a higher risk of various oral and systemic diseases. By synthesizing existing research, this study explores the potential of the connection between blood type ABO and ESR levels in individuals with periodontal disorders, examining studies that assess the distribution of ABO blood types and corresponding ESR values among periodontal patients.

Do We Need Preoperative Antibiotics in Common General Pediatric Surgery Procedures?

Background There are limited studies on the necessity of preoperative antibiotics in surgeries for undescended testis (UDT), inguinal hernia (IH), and umbilical hernia (UH) in children. Here, we investigated the relationship between preoperative antibiotic use and surgical site infection (SSI) incidence in surgeries for UDT, IH, and UH in children. Methods Patients who underwent surgery for IH were subdivided based on the surgical form into those who underwent (i) open IH (OIH) repair and (ii) laparoscopic percutaneous extraperitoneal closure (LPEC). Medical records of patients who underwent surgeries for UDT and IH or UH were retrospectively examined. The SSI incidence was compared between patients receiving and not receiving preoperative antibiotics. In patients who underwent surgery for UH or LPEC, the relative risk of SSI postoperatively in the inguinal region (including surgery for UDT and OIH repair) was examined. Results In total, 926 patients with 1389 wounds were included in this study. SSI rates in patients who underwent surgeries for UDT and UH, OIH repair, and LPEC were 0.2% and 2.7%, 0.3%, and 0.4%, respectively. These rates were not significantly different between patients receiving and not receiving preoperative antibiotics. In patients who underwent surgery for UH, the relative risk of SSI was statistically significant at 9.8 compared with that in patients who underwent surgeries in the inguinal region (95% CI = 1.3-74; p = 0.013). Conclusions Preoperative antibiotics are unnecessary in surgeries for UDT and OIH repair. Patients undergoing surgery for UH should be given extensive care as they are at a high risk of SSI.

Fracture-Related Infection of a Distal Femur Open Fracture Treated With a Supracutaneous Locking Plate.

Fracture-related infection (FRI) is a challenging complication in open fractures. It can cause major disability to patients and a burden to the public health sector. A multidisciplinary approach is required to eradicate infection and improve the quality of life for patients. We present a case of an FRI in an open fracture of the distal femur treated using a supracutaneous locking plate, which is an uncommon technique. This technique yields excellent outcomes in controlling local infection and providing satisfactory stability, especially for a peri-articular distal femur fracture with FRI. Therefore, supracutaneous plating using a locking plate can be considered an alternative option to conventional external fixations in managing FRIs.