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Carrier lifetime measurements were performed on deliberately Ti-doped multicrystalline silicon wafers using a temperature controlled photoconductance device. The dominant recombination center was found to be the double-donor level associated with interstitial titanium. The interstitial Ti concentrations in multicrystalline silicon wafers were determined by measuring the Shockley–Read–Hall time constant for holes and using the known values of the thermal velocity and capture cross section for holes of the double-donor level at different temperatures. The measured values of the Ti concentration were then used to determine the electron capture cross section of the double-donor level over the temperature range of 140–270 °C via the measured values of the Shockley–Read–Hall time constant for electrons and the known thermal velocity. Multiphonon emission was found to be the most likely capture mechanism for this temperature range for electron capture into the double-donor level of Ti in silicon. The effective segregation coefficient for Ti was estimated by fitting Scheil’s equation to the measured values of the Ti concentrations and their respective vertical positions in the ingot. If all Ti were present as the interstitial double-donor, a lower limit of 1.8×10-6 can be ascribed to the segregation coefficient, which is very close to the equilibrium value. [ABSTRACT FROM AUTHOR]

We report the case of 58-year-old man with pulmonary artery intimal sarcoma. He initially presented with cough, right-sided chest pain, and shortness of breath. Although the diagnosis of pulmonary embolism had been considered, chest radiograph and pulmonary perfusion scintigraphy showed a mass in the right hilum and no perfusion in the right lung. (18)F-fluorodeoxyglucose positron emission computed tomography (FDGPET) showed increased FDG uptake in the mass obstructing the right pulmonary artery. Fine-needle biopsy revealed a pathological diagnosis of pulmonary artery intimal sarcoma. The patient was successfully treated with radiotherapy and adjuvant chemotherapy. FDG-PET was used for monitoring the response to therapy. [ABSTRACT FROM AUTHOR]

Objective: In-111 ((111)In)-labeled octreotide has been clinically used for imaging somatostatin receptor-positive tumors, and radiolabeled octreotide analogs for positron emission tomography (PET) have been developed. Cu-64 ((64)Cu; half-life, 12.7 h) is an attractive radionuclide for PET imaging and is produced with high specific activity using a small biomedical cyclotron. The aim of this study is to produce and fundamentally examine a (64)Cu-labeled octreotide analog, (64)Cu-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-D: -Phe(1)-Tyr(3)-octreotide ((64)Cu-DOTA-TOC). Methods: (64)Cu produced using a biomedical cyclotron was reacted with DOTA-TOC for 30 min at 45 degrees C. The stability of (64)Cu-DOTA-TOC was evaluated in vitro (incubated with serum) and in vivo (blood collected after administration) by HPLC analysis. Biodistribution studies were performed in normal mice by administration of mixed solution of (64)Cu-DOTA-TOC and (111)In-DOTA-TOC and somatostatin receptor-positive U87MG tumor-bearing mice by administration of (64)Cu-DOTA-TOC or (64)Cu-1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid-octreotide ((64)Cu-TETA-OC). The tumor was imaged using (64)Cu-DOTA-TOC, (64)Cu-TETA-OC, and FDG with an animal PET scanner. Results: (64)Cu-DOTA-TOC can be produced in amounts sufficient for clinical study with high radiochemical yield. (64)Cu-DOTA-TOC was stable in vitro, but time-dependent transchelation to protein was observed after injection into mice. In biodistribution studies, the radioactivity of (64)Cu was higher than that of (111)In in all organs except kidney. In tumor-bearing mice, (64)Cu-DOTA-TOC showed a high accumulation in the tumor, and the tumor-to-blood ratio reached as high as 8.81 +/- 1.17 at 6 h after administration. (64)Cu-DOTA-TOC showed significantly higher accumulation in the tumor than (64)Cu-TETA-OC. (64)Cu-DOTA-TOC PET showed a very clear image of the tumor, which was comparable to that of (18)F-FDG PET and very similar to that of (64)Cu-TETA-OC. Conclusions: (64)Cu-DOTA-TOC clearly imaged a somatostatin receptor-positive tumor and seemed to be a potential PET tracer in the clinical phase. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the maximum-slope (MS) and dual-input one-compartment model (DOCM) methods in hepatic perfusion computed tomography (CT).Materials and Methods: A total of 37 patients with known or suspected liver disease underwent single-location dynamic CT after arterial or venous bolus injection of contrast material. Perfusion CT images were created by the MS (dividing the peak gradient of the time-attenuation curve by the peak vessel CT number) and DOCM-calculating from the equation dC ( L )(t)/dt = k ( a ) C ( a )(t - tau( a )) + k ( p ) C ( p )(t - tau( p )) - k ( v ) C ( L )(t)-methods. The perfusion parameters hepatic arterial perfusion (HAP), portal venous perfusion (PVP), and hepatic perfusion index (HPI) were determined.Results: The PVP of the tumor-free hepatic parenchyma determined by the MS method was lower than that obtained by the DOCM method (P < 0.001) with both injections. HAP determined by the MS method was lower than that obtained by the DOCM method with venous injection (P = 0.001), although there was no difference between the methods for HAP with arterial injection (P = 0.154). Most of the perfusion parameters showed linear correlations between the two analytical methods.Conclusion: Except for HAP with arterial injection, the perfusion parameters obtained with the MS method were lower than those obtained with the DOCM method. [ABSTRACT FROM AUTHOR]

We report the results of (18)F-fluorodeoxyglucose positron emission tomography (FDG PET) and immunohistochemical staining of glucose transporter 1 (Glut-1) and hexokinase II (HK-II) in patients with hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CCC) to observe the variation in (18)F-FDG uptake and variation in expression of Glut-1 and HK-II in these hepatic tumors. In the case of HCC, moderate (18)F-FDG uptake and strong expression of HK-II were detected, whereas Glut-1 was not expressed. Conversely, CCC showed high (18)F-FDG uptake and increased expression of Glut-1 but HK-II was not expressed. The variation in the (18)F-FDG uptake and expression of Glut 1 and HK-II in HCC and CCC might be owing to the difference in origin and the different mechanisms involved in glucose uptake, rate of glucose transporters, and hexokinase activity involved in the glycolytic pathway. [ABSTRACT FROM AUTHOR]

An analysis of all poisoning cases admitted in medical and pediatric wards of Patan Hospital for one year (1st Jan to 31st Dec 2004) was carried out. A total of 154 cases were admitted which was 0.8% of total hospital admissions. Females outnumbered males and almost two-thirds patients were young adults (15-34 years). Seasonal variation in poisoning was observed with more cases in the summer months. Organophosphorus compounds (42%), drugs (25%), and zinc phosphide (6.5%) were common poisonings in total and in adult populations, whereas kerosene was the most frequent poisoning in pediatric age group. Paracetamol, benzodiazepines, and tricyclic antidepressants were the most frequently used drugs. The circumstances of poisoning were intentional (75%) and accidental (20%);most of the childhood poisonings were accidental in nature. The mean hospital stay for all type of poisoning was 7.5 days; whereas it was 10.2 days for organophosphorus, 2.5 days for paracetamol, and 1.5 days each for zinc phosphide and kerosene ingestion. Intensive care unit (ICU) service was required in 17% of patients; and almost 25% developed complications. Aspiration pneumonia and respiratory failure were the most frequently observed complications. Ninety four percent of admitted patients recovered completely; leaving a mortality rate of 5%. [ABSTRACT FROM AUTHOR]

Background: Malignant peripheral sheath tumor (MPNST) is a rare, aggressive form of soft-tissue sarcoma that presents a unique set of diagnostic and treatment challenges and is associated with major unmet treatment medical needs., Objective: The chief aim of this review is to consider the epidemiology, histology, anatomic distribution, pathologic signaling pathways, diagnosis, and management of MPNST, with a focus on potential targeted therapies. A subordinate objective was to establish benchmarks for the antitumor activity of such treatments., Results: MPNST has an incidence of 1:100,000 in the general population and 1:3500 among patients with the inherited condition of neurofibromatosis-1. Spindle-cell sarcomas of neural-crest origin, MPNSTs are frequently situated in the extremities and pelvis/trunk, often at the confluence of large nerve roots and bundles. Highly copy-number aberrant and enriched in chromosome 8, MPNSTs have a complex molecular pathogenesis that likely involves the interplay of multiple signaling pathways, including Ras/AKT/mTOR/MAPK, EGFR, p53, PTEN, and PRC2, as well as factors in the tumor microenvironment. A combination of magnetic resonance imaging (MRI) and positron emission tomography with 18 F-fluorodeoxyglucose (FDG-PET) enables comprehensive assessment of both morphology and metabolism, while MRI- and ultrasound-guided core needle biopsy can confirm histopathology. Although surgery with wide excisional margins is now the chief curative approach to localized disease, MPNST-specific survival has not improved in decades. For advanced and metastatic MPNST, radiation and chemotherapy (chiefly with anthracyclines plus ifosfamide) have somewhat promising but still largely uncertain treatment roles, chiefly in local control, downstaging, and palliation. No single druggable target has emerged, no objective responses have been observed with a number of targeted therapies (cumulative disease control rate in our review = 22.9-34.8%), and combinatorial approaches directed toward multiple signal transduction mechanisms are hallmarks of ongoing clinical trials., Conclusions: Despite advances in our understanding of the genetics and molecular biology of MPNST, further research is warranted to: (1) unravel the complex pathogenesis of this condition; (2) improve diagnostic yield; (3) delineate the appropriate roles of chemotherapy and radiation; and (4) develop a targeted therapy (or combination of such treatments) that is well tolerated and prolongs survival., (© 2024. The Author(s).)

The pig is a natural host for influenza viruses and integrally involved in virus evolution through interspecies transmissions between humans and swine. Swine have many physiological, anatomical, and immunological similarities to humans, and are an excellent model for human influenza. Here, we employed single cell RNA-sequencing (scRNA-seq) and flow cytometry to characterize the major leukocyte subsets in bronchoalveolar lavage (BAL), twenty-one days after H1N1pdm09 infection or respiratory immunization with an adenoviral vector vaccine expressing hemagglutinin and nucleoprotein with or without IL-1β. Mapping scRNA-seq clusters from BAL onto those previously described in peripheral blood facilitated annotation and highlighted differences between tissue resident and circulating immune cells. ScRNA-seq data and functional assays revealed lasting impacts of immune challenge on BAL populations. First, mucosal administration of IL-1β reduced the number of functionally active Treg cells. Second, influenza infection upregulated IFI6 in BAL cells and decreased their susceptibility to virus replication in vitro. Our data provide a reference map of porcine BAL cells and reveal lasting immunological consequences of influenza infection and respiratory immunization in a highly relevant large animal model for respiratory virus infection., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Muir et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Mucosal-associated invariant T (MAIT) cells are a subset of unconventional T cells that recognize small molecule metabolites presented by major histocompatibility complex class I related protein 1 (MR1), via an αβ T cell receptor (TCR). MAIT TCRs feature an essentially invariant TCR α-chain, which is highly conserved between mammals. Similarly, MR1 is the most highly conserved major histocompatibility complex-I-like molecule. This extreme conservation, including the mode of interaction between the MAIT TCR and MR1, has been shown to allow for species-mismatched reactivities unique in T cell biology, thereby allowing the use of selected species-mismatched MR1-antigen (MR1-Ag) tetramers in comparative immunology studies. However, the pattern of cross-reactivity of species-mismatched MR1-Ag tetramers in identifying MAIT cells in diverse species has not been formally assessed. We developed novel cattle and pig MR1-Ag tetramers and utilized these alongside previously developed human, mouse, and pig-tailed macaque MR1-Ag tetramers to characterize cross-species tetramer reactivities. MR1-Ag tetramers from each species identified T cell populations in distantly related species with specificity that was comparable to species-matched MR1-Ag tetramers. However, there were subtle differences in staining characteristics with practical implications for the accurate identification of MAIT cells. Pig MR1 is sufficiently conserved across species that pig MR1-Ag tetramers identified MAIT cells from the other species. However, MAIT cells in pigs were at the limits of phenotypic detection. In the absence of sheep MR1-Ag tetramers, a MAIT cell population in sheep blood was identified phenotypically, utilizing species-mismatched MR1-Ag tetramers. Collectively, our results validate the use and define the limitations of species-mismatched MR1-Ag tetramers in comparative immunology studies., Competing Interests: Conflict of interest J. Y. W. M., L. L., D. P. F., A. J. C., J. M., and S. B. G. E. are inventors on university owned patent rights (patent families WO/2015/149130 and WO/2014/005194) licensed for commercial use to Immudex and for non-profit use to the NIH Tetramer Core Facility. All other authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Meningitis, though commonly caused by various infectious agents, may also have non-infectious aetiologies. The clinical presentation, however may be identical to infectious meningitis. We present a case of a female in her 50s who presented with fever, headache, vomiting and neck rigidity. She had features of inflammatory polyarthritis, cold sensitivity, puffy digits, alopecia and easy fatigability. No evidence of infection was found, and serological features consistent with mixed connective tissue disease (MCTD) were revealed, which led to the diagnosis of MCTD-related aseptic meningitis., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction/aims: Efgartigimod is a neonatal Fc receptor blocker and was the first approved medication in its class for the treatment of generalized myasthenia gravis (gMG). As a novel therapy, little is known about the use of efgartigimod in clinical practice. This study aims to describe how efgartigimod is being incorporated into the current therapeutic landscape of MG., Methods: We reviewed the charts of 17 patients with gMG treated with efgartigimod at the University of Pennsylvania between January 2022 and June 2023., Results: Efgartigimod was selected mainly for patients who were treatment refractory, had side effects to other treatments, and/or required quick improvement in their symptoms. All patients had been previously treated with at least one medication for MG and had an average baseline Myasthenia Gravis Activities of Daily Living (MG-ADL) score of 9.1. The patients treated with efgartigimod improved their MG-ADL score by an average of 5.5 points at 3 months (p < .001) and 7.1 points by 6 months (p < .001). Forty percent of patients achieved minimal symptom expression. Adverse events (AEs) were reported in 43.7% of patients on efgartigimod, the most common being mild infection (urinary tract infection and thrush). There were no serious AEs., Discussion: This study found efgartigimod to be efficacious, well tolerated, and safe in patients with MG. Efgartigimod should be considered as an add-on therapy, a bridge therapy, or as a monotherapy if patients have difficulty tolerating other treatments., (© 2023 Wiley Periodicals LLC.)

Cattle possess three IgG subclasses. However, the key immune functions, including complement and NK cell activation, and enhancement of phagocytosis, are not fully described for bovine IgG1, 2 and 3. We produced chimeric monoclonal antibodies (mAbs) consisting of a defined variable region linked to the constant regions of bovine IgG1, 2 and 3, and expressed His-tagged soluble recombinant bovine Fc gamma receptors (FcγRs) IA (CD64), IIA (CD32A), III (CD16) and Fcγ2R. Functional assays using bovinized mAbs were developed. IgG1 and IgG3, but not IgG2, activated complement-dependent cytotoxicity. Only IgG1 could activate cattle NK cells to mobilize CD107a after antigen crosslinking, a surrogate assay for antibody-dependent cell cytotoxicity. Both IgG1 and IgG2 could trigger monocyte-derived macrophages to phagocytose fluorescently labelled antigen-expressing target cells. IgG3 induced only weak antibody-dependent cellular phagocytosis (ADCP). By contrast, monocytes only exhibited strong ADCP when triggered by IgG2. IgG1 bound most strongly to recombinant FcγRs IA, IIA and III, with weaker binding by IgG3 and none by IgG2, which bound exclusively to Fcγ2R. Immune complexes containing IgG1, 2 and 3 bound differentially to leukocyte subsets, with IgG2 binding strongly to neutrophils and monocytes and all subclasses binding platelets. Differential expression of the FcγRs on leukocyte subsets was demonstrated by surface staining and/or RT-qPCR of sorted cells, e.g., Fcγ2R mRNA was expressed in monocytes/macrophages, neutrophils, and platelets, potentially explaining their strong interactions with IgG2, and FcγRIII was expressed on NK cells, presumably mediating IgG1-dependent NK cell activation. These data reveal differences in bovine IgG subclass functionality, which do not correspond to those described in humans, mice or pigs, which is relevant to the study of these IgG subclasses in vaccine and therapeutic antibody development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2023 Noble, Paudyal, Schwartz, Mwangi, Munir, Tchilian, Hammond and Graham.)

Monoclonal antibodies (mAbs) can be used to complement immunization for the therapy of influenza virus infection. We have established the pig, a natural large animal host for influenza A, with many physiological, immunological, and anatomical similarities to humans, as an appropriate model for testing mAbs. We have evaluated the protective efficacy of the strongly neutralizing human anti-hemagglutinin mAb, 2-12C in the pig influenza model. Intravenous administration of recombinant 2-12C reduced virus load and lung pathology, however, it did not prevent virus nasal shedding and, consequently, transmission. This may be because the pigs were directly infected intranasally with a high dose of the H1N1pdm09 virus. To address this, we developed a contact challenge model in which the animals were given 2-12C and one day later co-housed with donor pigs previously infected intra-nasally with H1N1pdm09. 2-12C pre-treatment completely prevented infection. We also administered a lower dose of 2-12C by aerosol to the respiratory tract, but this did not prevent shedding in the direct challenge model, although it abolished lung infection. We propose that the direct contact challenge model of pig influenza may be useful for evaluating candidate mAbs and emerging delivery platforms prior to clinical trials., Competing Interests: Author RM is an employee of the company Aerogen Limited. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 McNee, Vanover, Rijal, Paudyal, Lean, MacLoughlin, Núñez, Townsend, Santangelo and Tchilian.)

Porcine respiratory disease is multifactorial and most commonly involves pathogen co-infections. Major contributors include swine influenza A (swIAV) and porcine reproductive and respiratory syndrome (PRRSV) viruses. Experimental co-infection studies with these two viruses have shown that clinical outcomes can be exacerbated, but how innate and adaptive immune responses contribute to pathogenesis and pathogen control has not been thoroughly evaluated. We investigated immune responses following experimental simultaneous co-infection of pigs with swIAV H3N2 and PRRSV-2. Our results indicated that clinical disease was not significantly exacerbated, and swIAV H3N2 viral load was reduced in the lung of the co-infected animals. PRRSV-2/swIAV H3N2 co-infection did not impair the development of virus-specific adaptive immune responses. swIAV H3N2-specific IgG serum titers and PRRSV-2-specific CD8β + T-cell responses in blood were enhanced. Higher proportions of polyfunctional CD8β + T-cell subset in both blood and lung washes were found in PRRSV-2/swIAV H3N2 co-infected animals compared to the single-infected groups. Our findings provide evidence that systemic and local host immune responses are not negatively affected by simultaneous swIAV H3N2/PRRSV-2 co-infection, raising questions as to the mechanisms involved in disease modulation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Chrun, Maze, Roper, Vatzia, Paudyal, McNee, Martini, Manjegowda, Freimanis, Silesian, Polo, Clark, Besell, Booth, Carr, Edmans, Nunez, Koonpaew, Wanasen, Graham and Tchilian.)

T cell responses directed against highly conserved viral proteins contribute to the clearance of the influenza virus and confer broadly cross-reactive and protective immune responses against a range of influenza viruses in mice and ferrets. We examined the protective efficacy of mucosal delivery of adenoviral vectors expressing hemagglutinin (HA) and nucleoprotein (NP) from the H1N1 virus against heterologous H3N2 challenge in pigs. We also evaluated the effect of mucosal co-delivery of IL-1β, which significantly increased antibody and T cell responses in inbred Babraham pigs. Another group of outbred pigs was first exposed to pH1N1 as an alternative means of inducing heterosubtypic immunity and were subsequently challenged with H3N2. Although both prior infection and adenoviral vector immunization induced strong T-cell responses against the conserved NP protein, none of the treatment groups demonstrated increased protection against the heterologous H3N2 challenge. Ad-HA/NP+Ad-IL-1β immunization increased lung pathology, although viral load was unchanged. These data indicate that heterotypic immunity may be difficult to achieve in pigs and the immunological mechanisms may differ from those in small animal models. Caution should be applied in extrapolating from a single model to humans., Competing Interests: CT and SiS are employees of SIRION Biotech GmbH, a wholly-owned subsidiary of PerkinElmer Inc.. CT receives shares from the company. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Schmidt, Paudyal, Villanueva-Hernández, Mcnee, Vatzia, Carr, Schmidt, Mccarron, Martini, Schroedel, Thirion, Waters, Salguero, Gerner, Tenbusch and Tchilian.)

There is an urgent need for influenza vaccines providing broader protection that may decrease the need for annual immunization of the human population. We investigated the efficacy of heterologous prime boost immunization with chimpanzee adenovirus (ChAdOx2) and modified vaccinia Ankara (MVA) vectored vaccines, expressing conserved influenza virus nucleoprotein (NP), matrix protein 1 (M1) and neuraminidase (NA) in H1N1pdm09 pre-exposed pigs. We compared the efficacy of intra-nasal, aerosol and intra-muscular vaccine delivery against H3N2 influenza challenge. Aerosol prime boost immunization induced strong local lung T cell and antibody responses and abrogated viral shedding and lung pathology following H3N2 challenge. In contrast, intramuscular immunization induced powerful systemic responses and weak local lung responses but also abolished lung pathology and reduced viral shedding. These results provide valuable insights into the development of a broadly protective influenza vaccine in a highly relevant large animal model and will inform future vaccine and clinical trial design., (© 2023. The Author(s).)

The pig is an important agricultural species and powerful biomedical model. We have established the pig, a large natural host animal for influenza with many physiological similarities to humans, as a robust model for testing the therapeutic potential of monoclonal antibodies. Antibodies provide protection through neutralization and recruitment of innate effector functions through the Fc domain. However very little is known about the Fc-mediated functions of porcine IgG subclasses. We have generated 8 subclasses of two porcine monoclonal anti influenza hemagglutinin antibodies. We characterized their ability to activate complement, trigger cytotoxicity and phagocytosis by immune cells and assayed their binding to monocytes, macrophages, and natural killer cells. We show that IgG1, IgG2a, IgG2b, IgG2c and IgG4 bind well to targeted cell types and mediate complement mediated cellular cytotoxicity (CDCC), antibody dependent cellular cytotoxicity (ADCC) and antibody mediated cell phagocytosis (ADCP). IgG5b and IgG5c exhibited weak binding and variable and poor functional activity. Immune complexes of porcine IgG3 did not show any Fc-mediated functions except for binding to monocytes and macrophages and weak binding to NK cells. Interestingly, functionally similar porcine IgG subclasses clustered together in the genome. These novel findings will enhance the utility of the pig model for investigation of therapeutic antibodies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Paudyal, Mwangi, Rijal, Schwartz, Noble, Shaw, Sealy, Bonnet-Di Placido, Graham, Townsend, Hammond and Tchilian.)

In the light of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, we have developed a porcine respiratory coronavirus (PRCV) model for in depth mechanistic evaluation of the pathogenesis, virology and immune responses of this important family of viruses. Pigs are a large animal with similar physiology and immunology to humans and are a natural host for PRCV. Four PRCV strains were investigated and shown to induce different degrees of lung pathology. Importantly, although all four strains replicated equally well in porcine cell lines in vitro and in the upper respiratory tract in vivo , PRCV strains causing more severe lung pathology were also able to replicate in ex vivo tracheal organ cultures as well as in vivo in the trachea and lung. The time course of infection of PRCV 135, which caused the most severe pulmonary pathology, was investigated. Virus was shed from the upper respiratory tract until day 10 post infection, with infection of the respiratory mucosa, as well as olfactory and sustentacular cells, providing an excellent model to study upper respiratory tract disease in addition to the commonly known lower respiratory tract disease from PRCV. Infected animals made antibody and T cell responses that cross reacted with the four PRCV strains and Transmissible Gastroenteritis Virus. The antibody response was reproduced in vitro in organ cultures. Comparison of mechanisms of infection and immune control in pigs infected with PRCVs of differing pathogenicity with human data from SARS-CoV-2 infection and from our in vitro organ cultures, will enable key events in coronavirus infection and disease pathogenesis to be identified., Competing Interests: RM is an employee of company Aerogen. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Keep, Carr, Lean, Fones, Newman, Dowgier, Freimanis, Vatzia, Polo, Everest, Webb, Mcnee, Paudyal, Thakur, Nunez, MacLoughlin, Maier, Hammond, Bailey, Waters, Charleston, Tuthill, Britton, Bickerton and Tchilian.)

For the first time we have defined naïve, central memory, effector memory and differentiated effector porcine CD8 T cells and analyzed their distribution in lymphoid and respiratory tissues after influenza infection or immunization, using peptide-MHC tetramers of three influenza nucleoprotein (NP) epitopes. The hierarchy of response to the three epitopes changes during the response in different tissues. Most NP-specific CD8 T cells in broncho-alveolar lavage (BAL) and lung are tissue resident memory cells (TRM) that express CD69 and downregulate CD45RA and CCR7. NP-specific cells isolated from BAL express genes characteristic of TRM, but gene expression differs at 7, 21 and 63 days post infection. In all tissues the frequency of NP-specific CD8 cells declines over 63 days almost to background levels but is best maintained in BAL. The kinetic of influenza specific memory CD8 T cell in this natural host species differs from that in small animal models., (© 2022. The Author(s).)

We have established the pig, a large natural host animal for influenza, with many physiological similarities to humans, as a robust model for testing the therapeutic potential of monoclonal antibodies (mAbs). In this study we demonstrated that prophylactic intravenous administration of 15 mg/kg of porcine mAb pb18, against the K160-163 site of the hemagglutinin, significantly reduced lung pathology and nasal virus shedding and eliminated virus from the lung of pigs following H1N1pdm09 challenge. When given at 1 mg/kg, pb18 significantly reduced lung pathology and lung and BAL virus loads, but not nasal shedding. Similarly, when pb18 was given in combination with pb27, which recognized the K130 site, at 1 mg/kg each, lung virus load and pathology were reduced, although without an apparent additive or synergistic effect. No evidence for mAb driven virus evolution was detected. These data indicate that intravenous administration of high doses was required to reduce nasal virus shedding, although this was inconsistent and seldom complete. In contrast, the effect on lung pathology and lung virus load is consistent and is also seen at a one log lower dose, strongly indicating that a lower dose might be sufficient to reduce severity of disease, but for prevention of transmission other measures would be needed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Paudyal, McNee, Rijal, Carr, Nunez, McCauley, Daniels, Townsend, Hammond and Tchilian.)