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Non-invasive imaging techniques employing biomarkers with high selectivity for inflammation are essential not only for the early diagnosis and prevention of chronic inflammatory diseases but also for guiding appropriate drug therapy and enabling real-time evaluation of anti-inflammatory drug efficacy. In this study, we conjugated radioactive zirconium to sorbitol, a compound that can selectively target inflammation, and evaluated its inflammation-specific uptake and potential for assessing anti-inflammatory treatment efficacy in a mouse inflammation model. Pharmacokinetic analysis demonstrated that radiolabeled sorbitol achieved maximal uptake in inflamed tissues within 1 h. Positron emission tomography imaging further confirmed its utility in monitoring therapeutic effects during anti-inflammatory drug treatment. Our findings suggest that [89Zr]DTPA-sorbitol is a promising radioprobe for targeting rapid systemic inflammation, particularly in tissues demonstrating minimal non-specific uptake, such as the brain, heart, and lung tissues. Additionally, it holds significant potential for the in vivo evaluation of anti-inflammatory drug efficacy. [ABSTRACT FROM AUTHOR]

Fecal microbiota transplantation (FMT) and probiotics therapies represent key clinical options, yet their complex effects on the host are not fully understood. We evaluated the comprehensive effects of FMT using diarrheal or normal feces, as well as probiotic therapies, on multiple anatomical sites in healthy cynomolgus macaques through colonoscopy and surgery. Our research revealed that FMT led to a partial microbiome transplantation without exhibiting the donor's fecal clinical characteristics. Notably, FMT increased insulin and C-peptide levels in each animal according time series, regardless of fecal conditions. Immunologically, a reduction in neutrophil-to-lymphocyte ratio were exclusively observed in femoral veins of FMT group. In blood chemistry analyses, reductions in aspartate aminotransferase, blood urea nitrogen, and creatinine were observed in the femoral veins, while elevated levels of alanine aminotransferase and calcium were exclusively detected in the portal veins. These changes were not observed in the probiotic group. Also, short chain fatty acids were significantly higher increase in portal veins rather than femoral veins. Transcriptome analysis of liver tissues showed that metabolic pathways were primarily affected by both FMT and probiotics therapies. In summary, FMT therapy significantly influenced metabolic, immunologic and transcriptomic responses in normal macaque models, regardless of fecal conditions. Also, these macaque models, which utilize surgery and colonoscopy, serve as a human-like preclinical platform for evaluating long-term effects and anatomically specific responses to gut-targeted interventions, without the need for animal sacrifice. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a prevalent complication of diabetes, often resulting in vision loss and blindness. Existing treatments primarily aim to control blood sugar levels and inhibit angiogenesis. However, current therapies for DR, such as anti-VEGF and laser photocoagulation, are frequently invasive, and can cause adverse side effects. Consequently, there is a critical need for new preventive therapeutics to address DR more effectively. This study aimed to examine the therapeutic potential of a histamine H4 receptor (HRH4) antagonist as a preventive treatment for DR in mice. A mouse model of DR was established by intraperitoneally injecting 200 mg/kg of streptozotocin (STZ). Immune cell infiltration into the retina of mice with STZ-induced diabetes was measured using fluorescence-activated cell sorting (FACS) 12 weeks after STZ injection. The preventive effects of the HRH4 antagonist on inflammation and pathological retinal vessel leakage were determined in a mouse model of DR. Infiltration of HRH4-expressing macrophages increased in the retina of mice with STZ-induced DR. The HRH4 antagonist prevented macrophage infiltration and retinal vascular leakage to prevent STZ-induced DR in mice without causing any retinal toxicity. The infiltration of macrophages increased in the retina of mice with STZ-induced diabetes through HRH4, indicating that HRH4 is potentially a novel preventative therapeutic target in DR. These findings suggest that targeting HRH4 is a promising strategy for the prevention and treatment of DR. [ABSTRACT FROM AUTHOR]

The need for an accurate and rapid diagnosis platform for highly contagious viruses, such as pandemic viruses, has rapidly increased. Conventional diagnostic methods in the initial stage of quarantine for the prevention of epidemic spread have encountered limitations such as a long operation time, occupation of a large space, and high cost per single operation. Here, a highly sensitive and selective portable diagnostic platform based on solid‐phase photonic polymerase chain reaction (SP‐PCR) is reported. The thermal cycle is operated by the photothermal energy converted from the photon energy of a light‐emitting diode (LED) through a gold layer to phonons. The formation of an amplicon, which is immobilized through N‐heterocyclic carbene, is confirmed through fluorescence on the surface of the miniaturized SP‐PCR chip. The practical applicability of the newly developed diagnosis platform for the recognition of the presence of a SARS‐CoV‐2‐specific genome sequence is demonstrated utilizing 100 clinical samples, including 72 COVID‐19‐positive clinical samples and 28 negative samples. [ABSTRACT FROM AUTHOR]

Chronic HIV infection is associated with accumulation of germinal center (GC) T follicular helper (Tfh) cells in the lymphoid tissue. The GC Tfh cells can be heterogeneous based on the expression of chemokine receptors associated with T helper lineages, such as CXCR3 (Th1), CCR4 (Th2), and CCR6 (Th17). However, the heterogeneous nature of GC Tfh cells in the lymphoid tissue and its association with viral persistence and Ab production during chronic SIV/HIV infection are not known. To address this, we characterized the expression of CXCR3, CCR4, and CCR6 on GC Tfh cells in lymph nodes following SIVmac251 infection in rhesus macaques. In SIV-naive rhesus macaques, only a small fraction of GC Tfh cells expressed CXCR3, CCR4, and CCR6. However, during chronic SIV infection, the majority of GC Tfh cells expressed CXCR3, whereas the proportion of CCR4(+) cells did not change, and CCR6(+) cells decreased. CXCR3(+), but not CXCR3(-), GC Tfh cells produced IFN-γ (Th1 cytokine) and IL-21 (Tfh cytokine), whereas both subsets expressed CD40L following stimulation. Immunohistochemistry analysis demonstrated an accumulation of CD4(+)IFN-γ(+) T cells within the hyperplastic follicles during chronic SIV infection. CXCR3(+) GC Tfh cells also expressed higher levels of ICOS, CCR5, and α4β7 and contained more copies of SIV DNA compared with CXCR3(-) GC Tfh cells. However, CXCR3(+) and CXCR3(-) GC Tfh cells delivered help to B cells in vitro for production of IgG. These data demonstrate that chronic SIV infection promotes expansion of Th1-biased GC Tfh cells, which are phenotypically and functionally distinct from conventional GC Tfh cells and contribute to hypergammaglobulinemia and viral reservoirs.

NADPH oxidase 2 (NOX2) is an enzyme responsible for generating reactive oxygen species, primarily found in phagocytes. Chronic Granulomatous Disease (CGD), along with bacterial infections such as Mycobacterium tuberculosis (Mtb), is a representative NOX2-deficient X-linked disease characterized by uncontrolled inflammation. However, the precise roles of host-derived factors that induce infection-mediated hyperinflammation in NOX2-deficient condition remain incompletely understood. To address this, we compared Mtb-induced pathogenesis in Nox2-/- and wild type (WT) mice in a sex-dependent manner. Among age- and sex-matched mice subjected to Mtb infection, male Nox2-/- mice exhibited a notable increase in bacterial burden and lung inflammation. This was characterized by significantly elevated pro-inflammatory cytokines such as G-CSF, TNF-α, IL-1α, IL-1β, and IL-6, excessive neutrophil infiltration, and reduced pulmonary lymphocyte levels as tuberculosis (TB) progressed. Notably, lungs of male Nox2-/- mice were predominantly populated with CD11bintLy6GintCXCR2loCD62Llo immature neutrophils which featured mycobacterial permissiveness. By diminishing total lung neutrophils or reducing immature neutrophils, TB immunopathogenesis was notably abrogated in male Nox2-/- mice. Ultimately, we identified G-CSF as the pivotal trigger that exacerbates the generation of immature permissive neutrophils, leading to TB immunopathogenesis in male Nox2-/- mice. In contrast, neutralizing IL-1α and IL-1β, which are previously known factors responsible for TB pathogenesis in Nox2-/- mice, aggravated TB immunopathogenesis. Our study revealed that G-CSF-driven immature and permissive pulmonary neutrophils are the primary cause of TB immunopathogenesis and lung hyperinflammation in male Nox2-/- mice. This highlights the importance of quantitative and qualitative control of pulmonary neutrophils to alleviate TB progression in a phagocyte oxidase-deficient condition. Author summary: While tuberculosis (TB) remains a global threat to public health, the immunologic factors contributing to TB susceptibility are not yet fully defined. To enhance our understanding of TB immunopathogenesis, we utilized TB-susceptible male Nox2-/- mice to dissect the immunologic factors accelerating TB pathogenesis. In this study, we observed that male Nox2-/- mice infected with Mycobacterium tuberculosis (Mtb) exhibited increased lung hyperinflammation and mycobacterial burden compared to female Nox2-/- mice and WT mice. Exacerbated TB immunopathogenesis in male Nox2-/- mice was strongly correlated with an extreme infiltration of pulmonary neutrophils and the loss of pulmonary lymphocytes. The pulmonary neutrophils in male Nox2-/- mice displayed immature phenotypes and mycobacterial permissiveness. The depletion of total neutrophils or the AM80-induced maturation of neutrophils ameliorated TB pathogenesis in Nox2-/- mice, reducing pulmonary neutrophil counts, lung hyperinflammation, and mycobacterial load. Furthermore, neutralization of G-CSF mitigated TB pathogenesis in male Nox2-/- mice by decreasing immature neutrophil counts. Thus, we identified that G-CSF-mediated generation of permissive immature neutrophils contributes to TB susceptibility in male Nox2-/- mice. [ABSTRACT FROM AUTHOR]

CD8 T cells play an important role in controlling viral infections. We investigated the in situ localization of simian immunodeficiency virus (SIV)-specific T cells in lymph and genital tissues from SIV-infected macaques using MHC-class I tetramers. The majority of tetramer-binding cells localized in T cell zones and were CD8(+). Curiously, small subpopulations of tetramer-binding cells that had little to no surface CD8 were detected in situ both early and late post-infection, and in both vaginally and rectally inoculated macaques. These tetramer(+)CD8(low/-) cells were more often localized in apparent B cell follicles relative to T cell zones and more often found near or within the genital epithelium than the submucosa. Cells analyzed by flow cytometry showed similar populations of cells. Further immunohistological characterization revealed small populations of tetramer(+)CD20(-) cells inside B cell follicles and that tetramer(+) cells did not stain with gammadelta-TCR nor CD4 antibodies. Negative control tetramer staining indicated that tetramer(+)CD8(low/-) cells were not likely NK cells non-specifically binding to MHC tetramers. These findings have important implications for SIV-specific and other antigen-specific T cell function in these specific tissue locations, and suggest a model in which antigen-specific CD8+ T cells down modulate CD8 upon entering B cell follicles or the epithelial layer of tissues, or alternatively a model in which only antigen-specific CD8 T cells that down-modulate CD8 can enter B cell follicles or the epithelium.

The E6 and E7 proteins of specific subtypes of human papillomavirus (HPV), including HPV 16 and 18, are highly associated with cervical cancer as they modulate cell cycle regulation. The aim of this study was to investigate the potential antitumor effects of a messenger RNA‐HPV therapeutic vaccine (mHTV) containing nononcogenic E6 and E7 proteins. To achieve this, C57BL/6j mice were injected with the vaccine via both intramuscular and subcutaneous routes, and the resulting effects were evaluated. mHTV immunization markedly induced robust T cell‐mediated immune responses and significantly suppressed tumor growth in both subcutaneous and orthotopic tumor‐implanted mouse model, with a significant infiltration of immune cells into tumor tissues. Tumor retransplantation at day 62 postprimary vaccination completely halted progression in all mHTV‐treated mice. Furthermore, tumor expansion was significantly reduced upon TC‐1 transplantation 160 days after the last immunization. Immunization of rhesus monkeys with mHTV elicited promising immune responses. The immunogenicity of mHTV in nonhuman primates provides strong evidence for clinical application against HPV‐related cancers in humans. All data suggest that mHTV can be used as both a therapeutic and prophylactic vaccine. [ABSTRACT FROM AUTHOR]

Recently emerging severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) Omicron variants are generally less pathogenic than previous strains. However, elucidating the molecular basis for pulmonary immune response alterations is challenging owing to the virus's heterogeneous distribution within complex tissue structure. Here, we revealed the spatial transcriptomic profiles of pulmonary microstructures at the SARS‐CoV‐2 infection site in the nine cynomolgus macaques upon inoculation with the Delta and Omicron variants. Delta‐ and Omicron‐infected lungs had upregulation of genes involved in inflammation, cytokine response, complement, cell damage, proliferation, and differentiation pathways. Depending on the tissue microstructures (alveoli, bronchioles, and blood vessels), there were differences in the types of significantly upregulated genes in each pathway. Notably, a limited number of genes involved in cytokine and cell damage response were differentially expressed between bronchioles of the Delta‐ and Omicron‐infection groups. These results indicated that despite a significant antigenic shift in SARS‐CoV‐2, the host immune response mechanisms induced by the variants were relatively consistent, with limited transcriptional alterations observed only in large airways. This study may aid in understanding the pathogenesis of SARS‐CoV‐2 and developing a clinical strategy for addressing immune dysregulation by identifying potential transcriptional biomarkers within pulmonary microstructures during infection with emerging variants. [ABSTRACT FROM AUTHOR]