House dust mite sensitization drives cross-reactive immune responses to homologous helminth proteins.

The establishment of type 2 responses driven by allergic sensitization prior to exposure to helminth parasites has demonstrated how tissue-specific responses can protect against migrating larval stages, but, as a consequence, allow for immune-mediated, parasite/allergy-associated morbidity. In this way, whether helminth cross-reacting allergen-specific antibodies are produced and play a role during the helminth infection, or exacerbate the allergic outcome awaits elucidation. Thus, the main objective of the study was to investigate whether house dust mite (HDM) sensitization triggers allergen-specific antibodies that interact with Ascaris antigens and mediate antibody-dependent deleterious effects on these parasites as well as, to assess the capacity of cross-reactive helminth proteins to trigger allergic inflammation in house dust mite presensitized mice. Here, we show that the sensitization with HDM-extract drives marked IgE and IgG1 antibody responses that cross-react with Ascaris larval antigens. Proteomic analysis of Ascaris larval antigens recognized by these HDM-specific antibodies identified Ascaris tropomyosin and enolase as the 2 major HDM homologues based on high sequence and structural similarity. Moreover, the helminth tropomyosin could drive Type-2 associated pulmonary inflammation similar to HDM following HDM tropomyosin sensitization. The HDM-triggered IgE cross-reactive antibodies were found to be functional as they mediated immediate hypersensitivity responses in skin testing. Finally, we demonstrated that HDM sensitization in either B cells or FcγRIII alpha-chain deficient mice indicated that the allergen driven cell-mediated larval killing is not antibody-dependent. Taken together, our data suggest that aeroallergen sensitization drives helminth reactive antibodies through molecular and structural similarity between HDM and Ascaris antigens suggesting that cross-reactive immune responses help drive allergic inflammation.

Serosurvey of Immunity to Monkeypox (Mpox) Virus Antigens in People Living with HIV in South Florida.

Mpox is an infectious disease caused by the monkeypox virus (MPXV) belonging to the Orthopoxvirus (OPXV) genus, which includes smallpox and vaccinia virus (VACV). A global mpox outbreak which began in May 2022 has infected more than 88,000 people. VACV-based vaccines provide protection against mpox disease but complicate the use of serological assays for disease surveillance. We tested the reactivity of serum IgG from Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN)-vaccinated (n = 12) and convalescent mpox-infected (n = 5) individuals and uninfected, non-vaccinated controls (n = 32) to MPXV/VACV proteins A27, A29, A30, A35, B16, B21, C19, D6, E8, H3, I1, and L1. Using a subset of MPXV antigen-based assays (A35, B16, E8, H3, and I1), we conducted a mpox antibody survey of serum from 214 individuals, including 117 (54.7%) people with HIV (PWH) collected between June 2022 and January 2023, excluding individuals who reported recent mpox vaccination or infection, and 32 young, pre-pandemic controls. The convalescent sera reacted strongly to most tested antigens. Vaccine sera responses were limited to A35, E8, H3, and I1. IgG antibody to E8 was markedly elevated in all vaccinated individuals. B16 IgG showed high sensitivity (100% [95% CI: 56.55-100.0%]) and specificity (91.67% [64.61-99.57%]) for distinguishing infection from MVA-BN vaccination, while E8 IgG showed 100% [75.75-100] sensitivity and 100% [79.61-100] specificity for detecting and distinguishing vaccinated individuals from controls. We identified 11/214 (5.1%) recent serum samples and 1/32 (3.1%) young, pre-pandemic controls that were seropositive for ≥2 MPXV antibodies, including 6.8% of PWH. Seropositivity was 10/129 (7.8%) among males compared to 1/85 (1.2%) among females. Our findings provide insight into the humoral immune response to mpox and demonstrate the usefulness of inexpensive, antigen-based serosurveillance in identifying asymptomatic or unreported infections.

Secreted heat shock protein gp96-Ig and OX40L-Fc combination vaccine enhances SARS-CoV-2 Spike (S) protein-specific B and T cell immune responses.

Encouraging protection results from current mRNA-based SARS-CoV-2 vaccine platforms are primarily due to the induction of SARS- CoV-2- specific B cell antibody and CD4 + T cell. Even though, current mRNA vaccine platforms are adept in inducing SARS-CoV2-specific CD8 + T cell, much less is known about CD8 T cells contribution to the overall vaccine protection. Our allogeneic cellular vaccine, based on a secreted form of the heat-shock protein gp96-Ig, achieves high frequencies of polyclonal CD8 + T cell responses to tumor and infectious antigens through antigen cross-priming in vivo. We and others have shown that gp96-Ig, in addition to antigen-specific CD8 + T cell anti-tumor and anti-pathogen immunity, primes antibody responses as well. Here, we generated a cell-based vaccine that expresses SARS-Cov-2 Spike (S) protein and simultaneously secretes gp96-Ig and OX40L-Fc fusion proteins. We show that co-secretion of gp96-Ig-S peptide complexes and the OX40L-Fc costimulatory fusion protein in allogeneic cell lines results in enhanced activation of S protein-specific IgG antibody responses. These findings were further strengthened by the observation that this vaccine platform induces T follicular helper cells (TFH) and protein-S -specific CD8 + T cells. Thus, a cell-based gp96-Ig vaccine/OX40-L fusion protein regimen provides encouraging translational data that this vaccine platform induces pathogen-specific CD8+, CD4 + T and B cell responses, and may cohesively work as a booster for FDA-approved vaccines. Our vaccine platform can be rapidly engineered and customized based on other current and future pathogen sequences.

Helminth-Induced Human Gastrointestinal Dysbiosis: a Systematic Review and Meta-Analysis Reveals Insights into Altered Taxon Diversity and Microbial Gradient Collapse.

High-throughput 16S rRNA sequencing has allowed the characterization of helminth-uninfected (HU) and helminth-infected (HI) gut microbiomes, revealing distinct profiles. However, there have been no qualitative or quantitative syntheses of these studies, which show marked variation in participant age, diet, pathogen of interest, and study location. A predefined minimally biased search strategy identified 23 studies in humans. For each of these studies, we qualitatively addressed the effects of helminth infection on within-individual (alpha) and between-individual (beta) fecal microbiome diversity, infection-associated microbial taxa, the effect of helminth clearance on microbiome composition, microbiome composition as a predictor of infection status or treatment outcome, and treatment-specific effects on the fecal microbiome. Concomitantly, we performed a meta-analysis on a subset of 7 of these studies containing raw, paired-end 16S reads and individual-level metadata, comprising 424 pretreatment or untreated HI individuals and 497 HU controls. After reducing the batch effect and adjusting for age, our data demonstrated that intestinal helminth parasites can alter the host gut microbiome by increasing alpha diversity and promoting taxonomic reassortment and gradient collapse. Most strongly influencing the microbiome composition were the helminths found in the large intestine, Enterobius vermicularis and Trichuris trichiura, suggesting that this influence appears to be specific to soil-transmitted helminths (STH) species and host anatomical niche. In summary, using a large and diverse sample set captured in the meta-analysis, we were able to evaluate the influence of individual helminth species as well as species-species interactions, each of which explained a significant portion of the variation in the microbiome. IMPORTANCE The gut microbiome has established importance in regulating many aspects of human health, including nutrition and immunity. While many internal and environmental factors are known to influence the microbiome, less is known about the effects of intestinal helminth parasites (worms), which together affect one-sixth of the world's population. Through a comprehensive qualitative systematic review and quantitative meta-analysis of existing literature, we provide strong evidence that helminth infection dynamically shifts the intestinal microbiome structure. Moreover, we demonstrated that such influence seems to be specific to helminth species and host anatomical niche. Our findings suggest that the gut microbiome may underlie some of the pathology associated with intestinal worm infection and support future work to understand the precise nature of the helminth-microbiome relationship.

Isolation and characterization of a novel bacteriophage WO from Allonemobius socius crickets in Missouri.

Wolbachia are endosymbionts of numerous arthropod and some nematode species, are important for their development and if present can cause distinct phenotypes of their hosts. Prophage DNA has been frequently detected in Wolbachia, but particles of Wolbachia bacteriophages (phage WO) have been only occasionally isolated. Here, we report the characterization and isolation of a phage WO of the southern ground cricket, Allonemobius socius, and provided the first whole-genome sequence of phage WO from this arthropod family outside of Asia. We screened A. socius abdomen DNA extracts from a cricket population in eastern Missouri by quantitative PCR for Wolbachia surface protein and phage WO capsid protein and found a prevalence of 55% and 50%, respectively, with many crickets positive for both. Immunohistochemistry using antibodies against Wolbachia surface protein showed many Wolbachia clusters in the reproductive system of female crickets. Whole-genome sequencing using Oxford Nanopore MinION and Illumina technology allowed for the assembly of a high-quality, 55 kb phage genome containing 63 open reading frames (ORF) encoding for phage WO structural proteins and host lysis and transcriptional manipulation. Taxonomically important regions of the assembled phage genome were validated by Sanger sequencing of PCR amplicons. Analysis of the nucleotides sequences of the ORFs encoding the large terminase subunit (ORF2) and minor capsid (ORF7) frequently used for phage WO phylogenetics showed highest homology to phage WOAu of Drosophila simulans (94.46% identity) and WOCin2USA1 of the cherry fruit fly, Rhagoletis cingulata (99.33% identity), respectively. Transmission electron microscopy examination of cricket ovaries showed a high density of phage particles within Wolbachia cells. Isolation of phage WO revealed particles characterized by 40-62 nm diameter heads and up to 190 nm long tails. This study provides the first detailed description and genomic characterization of phage WO from North America that is easily accessible in a widely distributed cricket species.

Whipworm-Associated Intestinal Microbiome Members Consistent Across Both Human and Mouse Hosts.

The human whipworm Trichuris trichiura infects 289 million people worldwide, resulting in substantial morbidity. Whipworm infections are difficult to treat due to low cure rates and high reinfection rates. Interactions between whipworm and its host's intestinal microbiome present a potential novel target for infection control or prevention but are very complicated and are identified using inconsistent methodology and sample types across the literature, limiting their potential usefulness. Here, we used a combined 16S rRNA gene OTU analysis approach (QIIME2) for samples from humans and mice infected with whipworm (T. trichiura and T. muris, respectively) to identify for the first time, bacterial taxa that were consistently associated with whipworm infection spanning host species and infection status using four independent comparisons (baseline infected vs uninfected and before vs after deworming for both humans and mice). Using these four comparisons, we identified significant positive associations for seven taxa including Escherichia, which has been identified to induce whipworm egg hatching, and Bacteroides, which has previously been identified as a major component of the whipworm internal microbiome. We additionally identified significant negative associations for five taxa including four members of the order Clostridiales, two from the family Lachnospiraceae, including Blautia which was previously identified as positively associated with whipworm in independent human and mouse studies. Using this approach, bacterial taxa of interest for future association and mechanistic studies were identified, and several were validated by RT-qPCR. We demonstrate the applicability of a mouse animal model for comparison to human whipworm infections with respect to whipworm-induced intestinal microbiome disruption and subsequent restoration following deworming. Overall, the novel cross-species analysis approach utilized here provides a valuable research tool for studies of the interaction between whipworm infection and the host intestinal microbiome.

Systems analysis-based assessment of post-treatment adverse events in lymphatic filariasis.

BACKGROUND: Lymphatic filariasis (LF) is a neglected tropical disease, and the Global Program to Eliminate LF delivers mass drug administration (MDA) to 500 million people every year. Adverse events (AEs) are common after LF treatment. METHODOLOGY/PRINCIPAL FINDINGS: To better understand the pathogenesis of AEs, we studied LF-patients from a treatment trial. Plasma levels of many filarial antigens increased post-treatment in individuals with AEs, and this is consistent with parasite death. Circulating immune complexes were not elevated in these participants, and the classical complement cascade was not activated. Multiple cytokines increased after treatment in persons with AEs. A transcriptomic analysis was performed for nine individuals with moderate systemic AEs and nine matched controls. Differential gene expression analysis identified a significant transcriptional signature associated with post-treatment AEs; 744 genes were upregulated. The transcriptional signature was enriched for TLR and NF-κB signaling. Increased expression of seven out of the top eight genes upregulated in persons with AEs were validated by qRT-PCR, including TLR2. CONCLUSIONS/SIGNIFICANCE: This is the first global study of changes in gene expression associated with AEs after treatment of lymphatic filariasis. Changes in cytokines were consistent with prior studies and with the RNAseq data. These results suggest that Wolbachia lipoprotein is involved in AE development, because it activates TLR2-TLR6 and downstream NF-κB. Additionally, LPS Binding Protein (LBP, which shuttles lipoproteins to TLR2) increased post-treatment in individuals with AEs. Improved understanding of the pathogenesis of AEs may lead to improved management, increased MDA compliance, and accelerated LF elimination.