Salivary factor LTRIN from Aedes aegypti facilitates the transmission of Zika virus by interfering with the lymphotoxin-ß receptor.

Pathogens have co-evolved with mosquitoes to optimize transmission to hosts. Mosquito salivary-gland extract is known to modulate host immune responses and facilitate pathogen transmission, but the underlying molecular mechanisms of this have remained unknown. In this study, we identified and characterized a prominent 15-kilodalton protein, LTRIN, obtained from the salivary glands of the mosquito Aedes aegypti. LTRIN expression was upregulated in blood-fed mosquitoes, and LTRIN facilitated the transmission of Zika virus (ZIKV) and exacerbated its pathogenicity by interfering with signaling through the lymphotoxin-ß receptor (LTßR). Mechanically, LTRIN bound to LTßR and 'preferentially' inhibited signaling via the transcription factor NF-κB and the production of inflammatory cytokines by interfering with the dimerization of LTßR during infection with ZIKV. Furthermore, treatment with antibody to LTRIN inhibited mosquito-mediated infection with ZIKV, and abolishing LTßR potentiated the infectivity of ZIKV both in vitro and in vivo. This study provides deeper insight into the transmission of mosquito-borne diseases in nature and supports the therapeutic potential of inhibiting the action of LTRIN to disrupt ZIKV transmission.

H2A.Z facilitates licensing and activation of early replication origins.

DNA replication is a tightly regulated process that ensures the precise duplication of the genome during the cell cycle1. In eukaryotes, the licensing and activation of replication origins are regulated by both DNA sequence and chromatin features2. However, the chromatin-based regulatory mechanisms remain largely uncharacterized. Here we show that, in HeLa cells, nucleosomes containing the histone variant H2A.Z are enriched with histone H4 that is dimethylated on its lysine 20 residue (H4K20me2) and with bound origin-recognition complex (ORC). In vitro studies show that H2A.Z-containing nucleosomes bind directly to the histone lysine methyltransferase enzyme SUV420H1, promoting H4K20me2 deposition, which is in turn required for ORC1 binding. Genome-wide studies show that signals from H4K20me2, ORC1 and nascent DNA strands co-localize with H2A.Z, and that depletion of H2A.Z results in decreased H4K20me2, ORC1 and nascent-strand signals throughout the genome. H2A.Z-regulated replication origins have a higher firing efficiency and early replication timing compared with other origins. Our results suggest that the histone variant H2A.Z epigenetically regulates the licensing and activation of early replication origins and maintains replication timing through the SUV420H1-H4K20me2-ORC1 axis.

Author Correction: H2A.Z facilitates licensing and activation of early replication origins.

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

iNKT subsets differ in their developmental and functional requirements on Foxo1.

Invariant natural killer T (iNKT) cells play important roles in regulating immune responses. Based on cytokine profiling and key transcriptional factors, iNKT cells are classified into iNKT1, iNKT2, and iNKT17 subsets. However, whether the development and functions of these subsets are controlled by distinct mechanisms remains unclear. Here, we show that forkhead box protein O1 (Foxo1) promotes differentiation of iNKT1 and iNKT2 cells but not iNKT17 cells because of its distinct contributions to IL7R expression in these subsets. Nuclear Foxo1 is essential for Il7r expression in iNKT1 and iNKT2 cells at early stages of differentiation but is dispensable in iNKT17 cells. RORγt, instead of Foxo1, promotes IL7R expression in iNKT17 cells. Additionally, Foxo1 is required for the effector function of iNKT1 and iNKT2 cells but not iNKT17 cells. Cytoplasmic Foxo1 promotes activation of mTORC1 in iNKT1 and iNKT2 cells through inhibiting TSC1-TSC2 interaction, whereas it is dispensable for mTORC1 activation in iNKT17 cells. iNKT17 cells display distinct metabolic gene expression patterns from iNKT1 and iNKT2 cells that match their different functional requirements on Foxo1. Together, our results demonstrate that iNKT cell subsets differ in their developmental and functional requirements on Foxo1.

Elaborate Report of Allium sativum Clove Brown Rot Caused by Fusarium solani in China.

In September 2023, brown rot disease was observed on cloves of garlic (Allium sativum) variety "Zipi-1" (purple skin) collected from Jinxiang County, China during scientific research at the Beijing Academy of Agricultural and Forestry Sciences after being planted in nutrient soil for approximately 2 weeks in a growth chamber maintaining 22℃, 60% relative humidity, and 16 hours of light. Out of the 90 garlic cloves investigated, 18 showed signs of decay, characterized by a brown color and rot, with the surface covered in blue and white mold layers. Six symptomatic cloves were collected for isolating the pathogen using the method described in a previous study (Wu et al. 2021). After 2 d of incubation, individual spores were harvested from the fungal colonies and recultured. Single-spore cultures growing on PDA medium appeared white and flocculent when viewed from the top, and yellowish-brown when viewed from the bottom. After 5 d of cultivation, the colonies had a diameter of approximately 5.8 cm and microscopic examination revealed that the mycelium had a diameter of about 9-13 µm (Fig. S1a, b and c). Isolate As1 produced three types of spores: oval-shaped chlamydospores with a diameter of approximately 6 µm, while spindle-shaped microconidia and sickle-shaped macroconidia measuring approximately 6-7 × 20-30 µm and 8 × 50 µm, respectively (Fig. S1d and e). The mycelial characteristics and reproductive structures of the isolates fit the morphological description of Fusarium solani (Xie et al. 2022). To confirm the identification, TEF1, RPB1 and RPB2 regions of the genome were amplified from three separate isolates (As1, As2, and As3) using EF1/EF2, RPB1-Fa/G2R, RPB2-5F2/7cR, and RPB2-7cF/11aR primer pairs (O'Donnell et al. 2022). The results indicated that the sequences of the three isolates were completely identical. Furthermore, the BLASTn comparison results of the TEF1 (OR916018, 710bp, 100%), RPB1 (OR916019, 1797bp, 99.8%), and RPB2 (OR916020, 1874bp, 100%) sequences in the FUSARIUM-ID v.3.0 database revealed that As1 was identified as F. solani species complex 5 (O'Donnell et al. 2022). To assess the pathogenicity of As1, the surface of healthy garlic cloves (n = 30) was spread with 106 microconidia/mL As1 suspension, while a control group (n = 30) was inoculated with sterile water. All inoculated cloves were placed in an artificial climate chamber under same conditions described above. After 10 d, all inoculated cloves exhibited rot symptoms consistent with those of the initially infected cloves identified in September 2023, while the control plant cloves remained asymptomatic (Fig. S2). Based on morphological and molecular characters (TEF1, RPB1, and RPB2), the reisolated pathogen from diseased plants was identical to the As1 isolate used for inoculation, and the disease assays were repeated twice. Fusarium spp. has been reported as the causal agent of garlic rot disease in several countries such as Mexico, America, and Russia (Gálvez and Palmero 2022). Tai (1979) previously published a report on the presence of F. solani in garlic; however, the content in the book is rather basic, lacking detailed information on the isolation, identification, and the potential for causing garlic diseases, whether postharvest or during growth. Our research can be considered a supplement and improvement to the study by Tai (1979) and lays the groundwork for future studies on management strategies to combat plant diseases caused by F. solani.

Gas Chromatography-Mass Spectrometry Metabolite Analysis Combined with Transcriptomics Reveals Genes Involved in Wax Biosynthesis in Allium fistulosum L.

Cuticular waxes are essential for protecting plants from various environmental stresses. Allium fistulosum serves as an excellent model for investigating the regulatory mechanisms underlying cuticular wax synthesis with notable epidermal wax characteristics. A combination of gas chromatography-mass spectrometry (GC-MS) metabolite analysis and transcriptomics was used to investigate variations in metabolites and gene expression patterns between the wild type (WT) and glossy mutant type (gl2) of A. fistulosum. The WT surface had a large number of acicular and lamellar waxy crystals, whereas the leaf surface of gl2 was essentially devoid of waxy crystals. And the results revealed a significant decrease in the content of 16-hentriacontanone, the principal component of cuticular wax, in the gl2 mutant. Transcriptomic analysis revealed 3084 differentially expressed genes (DEGs) between WT and gl2. Moreover, we identified 12 genes related to fatty acid or wax synthesis. Among these, 10 DEGs were associated with positive regulation of wax synthesis, whereas 2 genes exhibited negative regulatory functions. Furthermore, two of these genes were identified as key regulators through weighted gene co-expression network analysis. Notably, the promoter region of AfisC5G01838 (AfCER1-LIKE1) exhibited a 258-bp insertion upstream of the coding region in gl2 and decreased the transcription of the AfCER1-LIKE1 gene. This study provided insights into the molecular mechanisms governing cuticular wax synthesis in A. fistulosum, laying the foundation for future breeding strategies.

Amine-functionalized cotton for the treatment of oily wastewater.

Common commercial demulsifiers are typically made from ethylene oxide and propylene oxide. The production process is dangerous and complex, with poor adaptability and high cost. In this work, cotton modified with polyethylene polyamine was utilized as a demulsifier for the treatment of oily wastewater. The chemical structure and morphology of the as-prepared sample (CPN) were characterized by IR spectrum and SEM. The effect of CPN dosage, pH value, and salinity on the demulsification performance of oily wastewater was explored through the bottle tests. The results showed that the light transmittance of separated water was 81.7% and the corresponding deoiling rate was 98.5% when a CPN dosage of 25 mg/L was used at room temperature for 30 min. The interfacial properties were also systematically investigated, and the results indicated that CPN had better interfacial activity and a stronger reduction capability of interfacial tension compared to asphaltenes. The finding initiated and accelerated the demulsification process of oily wastewater. Based on the outstanding performance of this biomass-derived demulsifier, it shows promising potential for application in the treatment of oily wastewater.

CDK5RAP3, a UFL1 substrate adaptor, is crucial for liver development.

Protein modification by ubiquitin and ubiquitin-like proteins (UBLs) regulates numerous biological functions. The UFM1 system, a novel UBL conjugation system, is implicated in mouse development and hematopoiesis. However, its broad biological functions and working mechanisms remain largely elusive. CDK5RAP3, a possible ufmylation substrate, is essential for epiboly and gastrulation in zebrafish. Herein, we report a crucial role of CDK5RAP3 in liver development and hepatic functions. Cdk5rap3 knockout mice displayed prenatal lethality with severe liver hypoplasia, as characterized by delayed proliferation and compromised differentiation. Hepatocyte-specific Cdk5rap3 knockout mice suffered post-weaning lethality, owing to serious hypoglycemia and impaired lipid metabolism. Depletion of CDK5RAP3 triggered endoplasmic reticulum stress and activated unfolded protein responses in hepatocytes. We detected the in vivo interaction of CDK5RAP3 with UFL1, the defined E3 ligase in ufmylation. Notably, loss of CDK5RAP3 altered the ufmylation profile in liver cells, suggesting that CDK5RAP3 serves as a novel substrate adaptor for this UBL modification. Collectively, our study identifies CDK5RAP3 as an important regulator of ufmylation and suggests the involvement of ufmylation in mammalian development.

Type 3 Innate Lymphoid Cells Direct Goblet Cell Differentiation via the LT-LTßR Pathway during Listeria Infection.

As a specialized subset of intestinal epithelial cells (IECs), goblet cells (GCs) play an important role during the antibacterial response via mucin production. However, the regulatory mechanisms involved in GC differentiation and function during infection, particularly the role of immune cell-IEC cross-talk, remain largely unknown. In this study, using Villin∆Ltbr conditional knockout mice, we demonstrate that LTßR, expressed on IECs, is required for GC hyperplasia and mucin 2 (MUC2) expression during Listeria infection for host defense but not homeostatic maintenance in the naive state. Analysis of single gene-deficient mice revealed that the ligand lymphotoxin (LT), but not LIGHT, and type 3 innate lymphoid cells (ILC3s), but not conventional T cells, are required for MUC2-dependent Listeria control. Conditional deficiency of LT in ILC3s further confirmed the importance of LT signals derived from ILC3s. Lack of ILC3-derived LT or IEC-derived LTßR resulted in the defective expression of genes related to GC differentiation but was not correlated with IEC proliferation and cell death, which were found to be normal by Ki-67 and Annexin V staining. In addition, the alternative NF-κB signaling pathway (involving RelB) in IECs was found to be required for the expression of GC differentiation-related genes and Muc2 and required for the anti-Listeria response. Therefore, our data together suggest a previously unrecognized ILC3-IEC interaction and LT-LTßR-RelB signaling axis governing GC differentiation and function during Listeria infection for host defense.

Second-Shell Amino Acid R266 Helps Determine N-Succinylamino Acid Racemase Reaction Specificity in Promiscuous N-Succinylamino Acid Racemase/o-Succinylbenzoate Synthase Enzymes.

Catalytic promiscuity is the coincidental ability to catalyze nonbiological reactions in the same active site as the native biological reaction. Several lines of evidence show that catalytic promiscuity plays a role in the evolution of new enzyme functions. Thus, studying catalytic promiscuity can help identify structural features that predispose an enzyme to evolve new functions. This study identifies a potentially preadaptive residue in a promiscuous N-succinylamino acid racemase/o-succinylbenzoate synthase (NSAR/OSBS) enzyme from Amycolatopsis sp. T-1-60. This enzyme belongs to a branch of the OSBS family which includes many catalytically promiscuous NSAR/OSBS enzymes. R266 is conserved in all members of the NSAR/OSBS subfamily. However, the homologous position is usually hydrophobic in other OSBS subfamilies, whose enzymes lack NSAR activity. The second-shell amino acid R266 is close to the catalytic acid/base K263, but it does not contact the substrate, suggesting that R266 could affect the catalytic mechanism. Mutating R266 to glutamine in Amycolatopsis NSAR/OSBS profoundly reduces NSAR activity but moderately reduces OSBS activity. This is due to a 1000-fold decrease in the rate of proton exchange between the substrate and the general acid/base catalyst K263. This mutation is less deleterious for the OSBS reaction because K263 forms a cation-π interaction with the OSBS substrate and/or the intermediate, rather than acting as a general acid/base catalyst. Together, the data explain how R266 contributes to NSAR reaction specificity and was likely an essential preadaptation for the evolution of NSAR activity.

Genome-wide identification and expression analysis of the Brassica oleracea L. chitin-binding genes and response to pathogens infections.

MAIN CONCLUSION: Chitinase family genes were involved in the response of Brassica oleracea to Fusarium wilt, powdery mildew, black spot and downy mildew. Abstract Chitinase, a category of pathogenesis-related proteins, is believed to play an important role in defending against external stress in plants. However, a comprehensive analysis of the chitin-binding gene family has not been reported to date in cabbage (Brassica oleracea L.), especially regarding the roles that chitinases play in response to various diseases. In this study, a total of 20 chitinase genes were identified using a genome-wide search method. Phylogenetic analysis was employed to classify these genes into two groups. The genes were distributed unevenly across six chromosomes in cabbage, and all of them contained few introns (≤ 2). The results of collinear analysis showed that the cabbage genome contained 1-5 copies of each chitinase gene (excluding Bol035470) identified in Arabidopsis. The heatmap of the chitinase gene family showed that these genes were expressed in various tissues and organs. Two genes (Bol023322 and Bol041024) were relatively highly expressed in all of the investigated tissues under normal conditions, exhibiting the expression characteristics of housekeeping genes. In addition, under four different stresses, namely, Fusarium wilt, powdery mildew, black spot and downy mildew, we detected 9, 5, 8 and 8 genes with different expression levels in different treatments, respectively. Our results may help to elucidate the roles played by chitinases in the responses of host plants to various diseases.

Langerhans Cells Control Lymphatic Vessel Function during Inflammation via LIGHT-LTßR Signaling.

The lymphatic vasculature is an important route for dendritic cell (DC) or tumor cell migration from peripheral tissues to draining lymph nodes (DLNs). However, the underlying molecular and cellular mechanisms remain poorly understood. In this study, using conventional bone marrow chimeric mice and additional UVB radiation, we found that deficiency of LIGHT but not lymphotoxin (LT) α1ß2, likely on radioresistant Langerhans cells (LCs), resulted in impaired skin DC migration to DLNs during LPS-induced inflammation. In addition, LT ß receptor (LTßR), but not herpes virus entry mediator, was found to be the receptor of LIGHT controlling DC migration. Furthermore, conditional deficiency of LTßR in Tie2 cre or Lyve1 cre mice, but not in LTßR-deficient bone marrow chimeric mice, impaired DC migration, suggesting an important role of LTßR in radioresistant lymphatic endothelial cells (LECs), although the role of LTßR in blood endothelial cells remains intriguing. Mechanistically, the gene expression of both CCL21 and CCL19 was found to be reduced in skin LECs isolated from LC-LIGHT-conditionally deficient or Lyve1 cre Ltbr fl/fl mice compared with their controls upon LPS stimulation. Soluble recombinant LIGHT was able to upregulate CCL21 and CCL19 gene expression on SVEC4-10 endothelial cells. Doxycycline, an inhibitor of soluble LIGHT release in the inflamed skin, impaired skin CCL21 and CCL19 expression and DC migration. In addition, melanoma cell metastasis to DLNs was also inhibited in LC-LIGHT-conditionally deficient or Lyve1 cre Ltbr fl/fl mice. Together, our data suggest, to our knowledge, a previously unrecognized scenario in which LCs activate LECs via the LIGHT-LTßR signaling axis to promote DC migration or tumor cell metastasis.

Molecular Mechanism for Attractant Signaling to DHMA by E. coli Tsr.

The attractant chemotaxis response of Escherichia coli to norepinephrine requires that it be converted to 3,4-dihydroxymandelic acid (DHMA) by the monoamine oxidase TynA and the aromatic aldehyde dehydrogenase FeaB. DHMA is sensed by the serine chemoreceptor Tsr, and the attractant response requires that at least one subunit of the periplasmic domain of the Tsr homodimer (pTsr) has an intact serine-binding site. DHMA that is generated in vivo by E. coli is expected to be a racemic mixture of the (R) and (S) enantiomers, so it has been unclear whether one or both chiral forms are active. Here, we used a combination of state-of-the-art tools in molecular docking and simulations, including an in-house simulation-based docking protocol, to investigate the binding properties of (R)-DHMA and (S)-DHMA to E. coli pTsr. Our studies computationally predicted that (R)-DHMA should promote a stronger attractant response than (S)-DHMA because of a consistently greater-magnitude piston-like pushdown of the pTsr α-helix 4 toward the membrane upon binding of (R)-DHMA than upon binding of (S)-DHMA. This displacement is caused primarily by interaction of DHMA with Tsr residue Thr156, which has been shown by genetic studies to be critical for the attractant response to L-serine and DHMA. These findings led us to separate the two chiral species and test their effectiveness as chemoattractants. Both the tethered cell and motility migration coefficient assays validated the prediction that (R)-DHMA is a stronger attractant than (S)-DHMA. Our study demonstrates that refined computational docking and simulation studies combined with experiments can be used to investigate situations in which subtle differences between ligands may lead to diverse chemotactic responses.

RelB regulates the homeostatic proliferation but not the function of Tregs.

BACKGROUND: RelB, a member of the NF-κB family, plays a critical role in the development of T cells. However, the role of RelB in Foxp3+ regulatory T cells (Tregs) remains controversial. RESULTS: Using a bone marrow chimeric mouse model, we demonstrated that the expansion of Foxp3+ Tregs in vivo could be mediated by extrinsic mechanisms. RelB plays an important role in inhibiting the homeostatic proliferation of Tregs, but not their survival. Even with the heightened expansion, RelB-/- Treg cells displayed normal suppressive function in vitro. Among the expanded populations of Treg cells, most were nTreg cells; however, the population of iTregs did not increase. Mechanistically, RelB seems to regulate Treg proliferation independently of the signal transducer and activator of transcription 5 (STAT5) pathway. CONCLUSIONS: These data suggest that RelB regulates Treg proliferation independently of the STAT5 pathway, but does not alter the function of Tregs. Further studies are warranted to uncover such mechanisms.

Investigation of the mechanism of action of a potent pateamine A analog, des-methyl, des-amino pateamine A (DMDAPatA).

The natural product pateamineA (PatA) is a highly potent antiproliferative agent. PatA and the simplified analog desmethyl, desamino pateamineA (DMDAPatA) have exhibited cytotoxicity selective for rapidly proliferating cells, and have been shown to inhibit cap-dependent translation initiation through binding to eIF4A (eukaryotic initiation factor 4A) of the eIF4F complex. PatA and DMDAPatA are both known to stimulate the RNA-dependent ATPase, and ATP-dependent RNA helicase activities of eIF4A. The impact of other eIF4F components, eIF4E and eIF4G, on DMDAPatA action were investigated in vitro and in cultured mammalian cells. The perturbation of the eIF4A-eIF4G association was found to be eIF4E- and mRNA cap-dependent. An inhibitory effect on helicase activity of eIF4A was observed when it was part of a complex that mimicked the eIF4F complex. We propose a model of action for DMDAPatA (and by supposition PatA) where the cellular activity of the compound is dependent on an "active" eIF4F complex.

Synthetic Tigliane Intermediates Engage Thiols to Induce Potent Cell Line Selective Anti-Cancer Activity.

The tigliane ring system, which encompasses iconic members such as phorbol and TPA, is widely renowned due to numerous observations of displaying potent biological activity, and subsequent use as mainstream biochemical tools. Traditionally, naturally occurring phorboids are regarded as tumor promotors through PKC activation, although in recent times more highly oxidized natural derivatives have been identified as anti-tumor agents. In the view that only limited synthetic investigations toward skeletal stereochemical modification have been undertaken, non-natural systems could be useful for a better understanding of the tigliane pharmacophore via interrogation of cellular sensitivity. In this context the concise construction of a number of highly functionalized non-natural D-ring inverted phorbol esters were synthesized, via a rhodium-catalyzed [4+3] cycloaddition, and biologically evaluated using a range of cancer cell lines. The biological results highlight the notion that subtle changes in structure have dramatic effects on potency. Furthermore, although the non-natural derivatives did not outcompete the natural systems in the PKC-activation sensitive MCF7 cancer cell line, they outperformed in other cancer cell lines (MM96L and CAL27). This observation strongly suggested an alternate mode of action not involving activation of PKC, but instead involves thiol addition as indicated by glutathione addition and NF-κB reporter activity.

Deflating the lymph node.

Although the lymph node lymphatic vessel growth and development is positively regulated by B cells and macrophages, Kataru et al. (2011), in this issue of Immunity, show negative regulation of lymphatic vessels by interferon-γ from T cells.

Differential Roles of LTßR in Endothelial Cell Subsets for Lymph Node Organogenesis and Maturation.

Cellular cross-talk mediated by lymphotoxin αß-lymphotoxin ß receptor (LTßR) signaling plays a critical role in lymph node (LN) development. Although the major role of LTßR signaling has long been considered to occur in mesenchymal lymphoid tissue organizer cells, a recent study using a VE-cadherincreLtbrfl/fl mouse model suggested that endothelial LTßR signaling contributes to the formation of LNs. However, the detailed roles of LTßR in different endothelial cells (ECs) in LN development remain unknown. Using various cre transgenic mouse models (Tekcre , a strain targeting ECs, and Lyve1cre , mainly targeting lymphatic ECs), we observed that specific LTßR ablation in Tekcre+ or Lyve1cre+ cells is not required for LN formation. Moreover, double-cre-mediated LTßR depletion does not interrupt LN formation. Nevertheless, TekcreLtbrfl/fl mice exhibit reduced lymphoid tissue inducer cell accumulation at the LN anlagen and impaired LN maturation. Interestingly, a subset of ECs (VE-cadherin+Tekcre-low/neg ECs) was found to be enriched in transcripts related to hematopoietic cell recruitment and transendothelial migration, resembling LN high ECs in adult animals. Furthermore, endothelial Tek was observed to negatively regulate hematopoietic cell transmigration. Taken together, our data suggest that although Tekcre+ endothelial LTßR is required for the accumulation of hematopoietic cells and full LN maturation, LTßR in VE-cadherin+Tekcre-low/neg ECs in embryos might represent a critical portal-determining factor for LN formation.

T Cell-Derived Lymphotoxin Is Essential for the Anti-Herpes Simplex Virus 1 Humoral Immune Response.

B cell-derived lymphotoxin (LT) is required for the development of follicular dendritic cell clusters for the formation of primary and secondary lymphoid follicles, but the role of T cell-derived LT in antibody response has not been well demonstrated. We observed that lymphotoxin ß-receptor (LTßR) signaling is essential for optimal humoral immune response and protection against an acute herpes simplex virus 1 (HSV-1) infection. Blocking the LTßR pathway caused poor maintenance of germinal center B (GC-B) cells and follicular helper T (Tfh) cells. Using bone marrow chimeric mice and adoptive transplantation, we determined that T cell-derived LT played an indispensable role in the humoral immune response to HSV-1. Upregulation of gamma interferon by the LTßR-Ig blockade impairs the sustainability of Tfh-like cells, leading to an impaired humoral immune response. Our findings have identified a novel role of T cell-derived LT in the humoral immune response against HSV-1 infection.IMPORTANCE Immunocompromised people are susceptible to HSV-1 infection and lethal recurrence, which could be inhibited by anti-HSV-1 humoral immune response in the host. This study sought to explore the role of T cell-derived LT in the anti-HSV-1 humoral immune response using LT-LTßR signaling-deficient mice and the LTßR-Ig blockade. The data indicate that the T cell-derived LT may play an essential role in sustaining Tfh-like cells and ensure Tfh-like cells' migration into primary or secondary follicles for further maturation. This study provides insights for vaccine development against infectious diseases.

Ferritin nanoparticle-based SpyTag/SpyCatcher-enabled click vaccine for tumor immunotherapy.

Recently, tumor neoantigens have been attractive for development of personal therapeutic vaccines. However, how to instantly deliver multiple neoantigens for efficient anti-tumor immunity is still challenging. Here, we established a SpyCatcher-modified ferritin nanoparticle platform, which permits convenient and stable covalent conjugation with tumor specific antigens containing SpyTag in a click-link manner. These ferritin nanoparticles are rapidly drained to lymph nodes and target dendritic cells, especially CD8α+ population, upon subcutaneous immunization. Ferritin nanoparticles carrying HPV16 oncogene E7 peptide antigen or MC38 tumor derived mutant neoantigens elicit about 2-3 folds enhanced antigen-specific cytotoxic T lymphocyte (CTL) response than soluble peptide antigens and significantly suppress the growth of E7-related or MC38 tumors. The anti-tumor effect was further enhanced in combination with PD-1 checkpoint blockade. Together, our study provides a ferritin nanoparticle-based, SpyTag/SpyCatcher-enabled click vaccine platform, especially for personalized tumor immunotherapy.