CRISPR/Cas9-based genome editing has yet to be reported in species of the Platyhelminthes. We tested this approach by targeting omega-1 (ω1) of Schistosoma mansoni as proof of principle. This secreted ribonuclease is crucial for Th2 polarization and granuloma formation. Schistosome eggs were exposed to Cas9 complexed with guide RNA complementary to ω1 by electroporation or by transduction with lentiviral particles. Some eggs were also transfected with a single stranded donor template. Sequences of amplicons from gene-edited parasites exhibited Cas9-catalyzed mutations including homology directed repaired alleles, and other analyses revealed depletion of ω1 transcripts and the ribonuclease. Gene-edited eggs failed to polarize Th2 cytokine responses in macrophage/T-cell co-cultures, while the volume of pulmonary granulomas surrounding ω1-mutated eggs following tail-vein injection into mice was vastly reduced. Knock-out of ω1 and the diminished levels of these cytokines following exposure showcase the novel application of programmed gene editing for functional genomics in schistosomes.

Allergen-specific immunotherapy (AIT) facilitates long-term resolution of allergic morbidity resulting in reduced drug use and increased refractoriness to new sensitization. AIT effectiveness has been demonstrated in seasonal and perennial allergies, and insect stings. However, data and studies in AIT relative to cockroach (CR) allergy are relatively scarce. In this study, mice allergic to American CR (Periplaneta americana) were treated with a liposome (L)-entrapped vaccine made of mouse Tregitope289-Per a 9 of the CR, Tregitope167-Per a 9, or Per a 9 alone – or placebo. Allergic mice that received an individual vaccine intranasally had reduced Th2 response, reduced lung inflammation, and reduced respiratory tissue remodeling. However, only L-Tregitope289-Per a 9 and L-Tregitope167-Per a 9 induced expression of immunosuppressive cytokine genes (IL-10, TGF-β, and IL-35 for L-Tregitope289-Per a 9, and IL-10 and TGF-β for L-Tregitope167-Per a 9) and increment of idoleamine-2,3-dioxygenase 1 (IDO1), indicating that these vaccines caused allergic disease suppression and reversal of respiratory tissue remodeling via generation of regulatory lymphocytes. Liposome entrapped-recombinant Per a 9 (L-Per a 9) did not cause upregulation of immunosuppressive cytokine genes and IDO1 increment; rather, L-Per a 9 induced high expression of IFN-γ in lungs of treated mice, which resulted in mitigation of allergic manifestations. This study provides compelling evidence that both liposome-entrapped vaccines made of single refined major allergen alone and single refined major allergen linked with Tregitopes are effective for reducing allergen-mediated respiratory tissue inflammation and remodeling, but through different mechanisms.

34 35 CRISPR/Cas9 based genome editing has not yet been reported in schistosomes. Here, we tested 36 this approach by targeting omega-1 (ω1) of Schistosoma mansoni as a proof of principle. This 37 secreted ribonuclease is crucial for Th2 priming and granuloma formation, providing informative 38 immuno-pathological readouts for programmed genome editing. Schistosome eggs were either 39 exposed to recombinant Cas9 complexed with a synthetic guide RNA (sgRNA) complementary 40 to exon 6 of ω1 by electroporation or transduced with pseudotyped lentivirus encoding Cas9 and 41 the sgRNA. Some eggs were also transduced with a single stranded oligodeoxynucleotide donor 42 transgene that encoded six stop codons, flanked by 50 nt-long 5'-and 3'-microhomology arms 43 matching the predicted Cas9-catalyzed double stranded break (DSB) within ω1. CRISPResso 44 analysis of amplicons spanning the DSB revealed ~4.5% of the reads were mutated by insertions, 45deletions and/or substitutions, with an efficiency for homology directed repair of 0.19% insertion 46 of the donor transgene. Transcripts encoding ω1 were reduced >80%, and lysates of ω1-edited 47 eggs displayed diminished ribonuclease activity indicative that programmed editing mutated the 48 ω1 gene. Whereas soluble lysates of wild type eggs polarized Th2 cytokine responses including 49 IL-4 and IL-5 in human macrophage/T cell co-cultures, diminished levels of these cytokines 50followed the exposure to those of ω1-mutated schistosome eggs. Following injection of 51 schistosome eggs into the tail vein of BALB/c mice, the volume of pulmonary granulomas 52surrounding ω1-mutated eggs was 18-fold smaller than wild type eggs. Programmed genome 53 editing was active in schistosomes, Cas9-catalyzed chromosomal breakage was repaired by 54 homology directed repair and/or non-homologous end joining, and mutation of ω1 impeded the 55 capacity of schistosome eggs both to drive Th2 polarization and to provoke formation of 56 pulmonary circumoval granulomas. Knock-out of ω1 and the impaired immunological phenotype 57showcase the novel application of programmed gene editing in and functional genomics for 58 schistosomes. 59 60 61 Introduction 62 63Schistosomiasis is considered the most problematic of the human helminth diseases in terms of 64 morbidity and mortality [1][2][3][4]. The past decade has seen major advances in knowledge and 65 understanding of the pathophysiology, developmental biology, evolutionary relationships and 66 genome annotation of the human schistosomes [5][6][7][8][9][10][11][12][13][14][15][16]. Establishing CRISPR/Cas9 genome 67 editing in schistosomiasis would greatly enable effective functional genomics approaches. The 68 stable CRISPR/Cas9-based site-specific gene mutation and phenotyping will drive innovation 69 and a deeper understanding of schistosome pathogenesis, biology and evolution [17]. 70 71The schistosome egg plays a central role both in disease transmission and pathogenesis [1]. The 72 appearance of S. mansoni eggs in host tissues by six to seven week...

Allergen-specific-immunotherapy (ASIT) can cause long-term resolution of allergic diseases, reduces drug use and chances of new allergen sensitization. Nevertheless, therapeutic vaccine and data on ASIT efficacy for cockroach (CR) allergy are relatively scarce. In this study, efficacy and mechanism of a novel intranasal vaccine consisting of liposome (L)-entrapped mixture of American CR (Periplaneta americana) major allergen (Per a 9) and immunosuppressive protein of Brugia malayi nematode named transforming growth factor-beta homologue (TGH) in treatment of CR allergy were investigated along with two other vaccines (L-Per a 9 alone and L-TGH alone). All three vaccines could reduce pathogenic type 2 response and lung immunopathology in the vaccines-treated CR-allergic mice, but by different mechanisms. L-Per a 9 caused a deviation of the pathogenic type 2 to type 1 response (IFN-γ-upregulation), whereas the L-(TGH + Per a 9) and L-TGH generated regulatory immune responses including up-expression of immunosuppressive cytokine genes and increment of serum adenosine and lung indoleamine-2,3-dioxygenase-1 which are signatures of regulatory T cells (Tregs) and tolerogenic dendritic cells, respectively. The L-(TGH + Per a 9) should be further evaluated towards clinical application, as this vaccine has a propensity to induce broadly effective therapeutic effects for inhalant allergies.

BACKGROUND In a number of patients, post-acute COVID syndrome develops after acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Long COVID [LC]). Here, we examined the immune responses and clinical characteristics of individuals with LC compared to age- and gender-matched healthy recovered COVID individuals (HC) during the Omicron pandemic. Immune responses following BNT162b2 (Pfizer) booster are also determined. METHODS This retrospective cohort study included 292 patients (LC, 158; HC, 134) confirmed to have SARS-CoV-2 infection from January to August 2022. We determined anti-SARS-CoV-2 receptor-binding domain immunoglobulin G (anti-RBD IgG), surrogate virus neutralization test (sVNT), T-cell subsets, and neutralization of wild-type, BA.1 and BA.5. A subset of patients was voluntarily recruited for booster vaccination with BNT162b2 vaccine and immunogenicity was assessed 4weeks after vaccination. RESULTS Cycle thresholds were higher in the HC group than in the LC group (20.7 vs. 19.7; P<0.039). Anti-RBD IgG was higher at ≤56 days after COVID-19 onset (PC) in 3-dose vaccines compared with 2-dose vaccines in the LC group (P=0.02) and after 57-84 days PC in 3-dose vaccines in the HC group (P<0.001). The sVNT in LC was significantly high against Wuhan and sVNT was 30% lower against the Omicron than the Wuhan. sVNT was relatively sustained in 3-dose vaccines than ≤ 2-dose vaccines. sVNT in the HC group reached its peak at 57-84 days PC as compared with the LC group. CONCLUSIONS These findings imply that LC produced increased neutralizing antibody responses than those with HC. During the Omicron pandemic, immunity after LC has still waned; therefore, a booster vaccine may be needed after 2-3 months from last infection. (ClinicalTrials.gov number, NCT05484700)

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