The effect of gastrointestinal graft-versus-host disease and diarrhea on the pharmacokinetic profile of sotrovimab in hematopoietic stem cell transplant recipients.

BACKGROUND: Monoclonal antibodies (mAbs) are utilized broadly to treat cancer and infectious diseases, and mAb exposure (serum concentration over time) is one predictor of overall treatment efficacy. Herein, we present findings from a clinical trial evaluating the pharmacokinetics (PK) of the long-acting mAb sotrovimab targeting SARS-CoV-2 in hematopoietic cell transplant (HCT) recipients. METHODS: All participants received an intravenous infusion of sotrovimab within one week prior to initiating the pre-transplant preparative regimen. The serum concentration of sotrovimab was measured longitudinally for up to 24 weeks post-transplant. RESULTS: Compared to non-HCT participants, we found that mAb clearance was 10% and 26% higher in autologous and allogeneic HCT recipients, respectively. Overall sotrovimab exposure was approximately 15% lower in HCT recipients compared to non-HCT recipients. Exposure was significantly reduced in HCT recipients who developed diarrhea and lower gastrointestinal (GI) graft-versus-host disease (GVHD) post-transplant. CONCLUSIONS: These data show that sotrovimab exposure may be reduced in HCT recipients, possibly related to increased GI clearance in patients with GVHD. This phenomenon has implications for dose selection and duration of efficacy with sotrovimab and potentially other mAbs in this vulnerable patient population. Thus, mAb dose regimens developed in non-HCT populations may have to be optimized when applied to HCT populations.

Expansion of the HSV-2-specific T cell repertoire in skin after immunotherapeutic HSV-2 vaccine.

The skin at the site of HSV-2 reactivation is enriched for HSV-2-specific T cells. To evaluate whether an immunotherapeutic vaccine could elicit skin-based memory T cells, we studied skin biopsies and HSV-2-reactive CD4+ T cells from peripheral blood mononuclear cells (PBMCs) by T cell receptor ß (TRB) sequencing before and after vaccination with a replication-incompetent whole virus HSV-2 vaccine candidate (HSV529). The representation of HSV-2-reactive CD4+ TRB sequences from PBMCs in the skin TRB repertoire increased after the first vaccine dose. We found sustained expansion after vaccination of unique, skin-based T-cell clonotypes that were not detected in HSV-2-reactive CD4+ T cells isolated from PBMCs. In one participant a switch in immunodominance occurred with the emergence of a T cell receptor (TCR) αß pair after vaccination that was not detected in blood. This TCRαß was shown to be HSV-2-reactive by expression of a synthetic TCR in a Jurkat-based NR4A1 reporter system. The skin in areas of HSV-2 reactivation possesses an oligoclonal TRB repertoire that is distinct from the circulation. Defining the influence of therapeutic vaccination on the HSV-2-specific TRB repertoire requires tissue-based evaluation.

Repeated mRNA vaccination sequentially boosts SARS-CoV-2-specific CD8+ T cells in persons with previous COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) hybrid immunity is more protective than vaccination or previous infection alone. To investigate the kinetics of spike-reactive T (TS) cells from SARS-CoV-2 infection through messenger RNA vaccination in persons with hybrid immunity, we identified the T cell receptor (TCR) sequences of thousands of index TS cells and tracked their frequency in bulk TCRß repertoires sampled longitudinally from the peripheral blood of persons who had recovered from coronavirus disease 2019 (COVID-19). Vaccinations led to large expansions in memory TS cell clonotypes, most of which were CD8+ T cells, while also eliciting diverse TS cell clonotypes not observed before vaccination. TCR sequence similarity clustering identified public CD8+ and CD4+ TCR motifs associated with spike (S) specificity. Synthesis of longitudinal bulk ex vivo single-chain TCRß repertoires and paired-chain TCRÉ‘ß sequences from droplet sequencing of TS cells provides a roadmap for the rapid assessment of T cell responses to vaccines and emerging pathogens.

Characterizing Acute Low Back Pain in a Community-Based Cohort.

Acute low back pain (LBP) is a common experience, however, the associated pain severity, pain frequency, and characteristics of individuals with acute LBP in community settings have yet to be well understood. In this manuscript, three acute LBP severity categorization definitions were used based on LBP frequency combined with either 1) pain impact frequency (impact-based) or 2) pain intensity (intensity-based), as well as LBP pain interference frequency (interference only-based) severity categories. The purpose of this manuscript is to describe and then compare these acute LBP severity groups in the following characteristics: 1) sociodemographic, 2) general and physical health, and 3) psychological. This cross-sectional study used baseline data from 131 community-based participants with acute LBP (<4 weeks duration before screening and ≥30 pain-free days before acute LBP onset). Descriptive associations were calculated as prevalence ratios for categorical variables and Hedges' g for continuous variables. Our analyses identified several large associations for impact-based and intensity-based categories with global mental health, global physical health, STarT Back Screening Tool risk category, and general health. Larger associations were found with social constructs (racially and ethnically minoritized, performance of social roles, and isolation) when using the intensity-based versus impact-based categorization. The interference-based category did not capture as much variability between acute LBP severity categories. This study adds to the literature by providing standard ways to characterize community-based individuals experiencing acute LBP. The robust differences observed between these categorization approaches suggest that how we define acute LBP severity is consequential; these different approaches may be used to improve the early identification of factors potentially contributing to the development of chronic LBP.

Recruitment of naive CD4+ T cells by the recombinant zoster vaccine correlates with persistent immunity.

Herpes zoster (HZ) is a substantial problem for people with decreased cell-mediated immunity, including older adults. The first vaccine approved for HZ prevention, the zoster vaccine live (ZVL), which provided limited and short-lived protection, has been supplanted by the superior recombinant zoster vaccine (RZV), which provides robust and durable protection. To understand the mechanisms underlying the differential immunologic characteristics of the 2 vaccines, we used T cell receptor ß chain sequencing and peptide-MHC class II tetramer staining to analyze recombinant glycoprotein E-specific (gE-specific) CD4+ T cell clonotypes in RZV and ZVL recipients. Compared with ZVL, RZV expanded more gE-specific CD4+ clonotypes, with greater breadth and higher frequency of public clonotypes. RZV recruited a higher proportion of clonotypes from naive than from memory cells, while ZVL recruited equally from memory and naive compartments. Compared with memory-derived, naive-derived clonotypes were more likely to last 5 or more years after immunization. Moreover, the frequency of tetramer+ persistent clones correlated with the frequency of tetramer+ naive CD4+ prevaccination T cells. We conclude that the ability of RZV to recruit naive CD4+ T cells into the response may contribute to the durability of its effect. The abundance, breadth, and frequency of public clonotypes may further add to its protective effect.

Instrumental Color Measurements Have Relationships to Fat Smearing in Fresh Sausage.

Fat smearing, or poor fat particle definition, impacts the visual quality of sausage. However, objective methods of assessing fat smearing have not been identified. Therefore, the objective of this experiment was to determine the relationship between fat smearing and instrumental color analysis for fresh sausages to create a standard method for using instrumental color in fat smearing analysis. Meat blocks of pork (PK), beef (BF), and a mixture of pork and beef (P/B) were formed and processed at three different temperatures to create varying degrees of fat smearing. The average fat smearing score of each sausage was used to determine if a relationship existed with instrumental color measurements (CIE L*, a*, b*, and reflectance percentage at 580 nm and 630 nm) and color calculations. A correlation was observed for L* (R = -0.704) and the reflectance at 580 nm (R = -0.775) to PK fat smearing (p < 0.05). In P/B sausage, both reflectances at ratios between 630 nm and 580 nm were correlated to P/B fat smearing. No measurement or calculation was correlated with BF fat smearing (p > 0.05). Therefore, it is possible to use instrumental color analysis for the evaluation of fat smearing in pork and pork/beef blended sausage products, but not in beef sausage products.

Successful Treatment of Persistent Symptomatic Coronavirus Disease 19 Infection With Extended-Duration Nirmatrelvir-Ritonavir Among Outpatients With Hematologic Cancer.

Persistent symptomatic coronavirus disease 2019 (COVID-19) is a distinct clinical entity among patients with hematologic cancer and/or profound immunosuppression. The optimal medical management is unknown. We describe 2 patients who had symptomatic COVID-19 for almost 6 months and were successfully treated in the ambulatory setting with extended courses of nirmatrelvir-ritonavir.

Are equitable physical performance tests perceived to be fair? Understanding officer cadets' perceptions of fitness standards.

In the last few decades, the armed forces in Western countries such as Canada and the United States have accepted women into virtually all military occupations. Despite this, a growing body of research confirms that female service members face prejudiced treatment while conducting their work in these organizations that continue to be predominately masculine and male-dominated. In particular, women attending the Canadian Military Colleges (CMCs) experience gender-related conflicts arising from the dissimilar fitness test standards between male and female cadets. There have been, however, few studies that scrutinize the psychological mechanisms of these tensions. The aim of this study was to unpack the existing biased perceptions against women pertaining to physical fitness through ambivalent sexism, social dominance orientation, and right-wing authoritarianism. Officer and naval cadets (n = 167, 33.5% women) at the Royal Military College of Canada (RMC) completed survey measures. Indirect effect analyses showed that cadets who viewed the fitness standards to be unfair expressed more hostile rather than benevolent sexist outlooks against women, and these negative feelings were connected to greater levels of social dominance and right-wing authoritarianism. These results indicate that sexist beliefs, competitive worldviews, and authoritarianism are underlying attitudes that should be addressed by militaries striving to fully integrate women into their forces.

Spike-specific T cells are enriched in breastmilk following SARS-CoV-2 mRNA vaccination.

Human breastmilk is rich in T cells; however, their specificity and function are largely unknown. We compared the phenotype, diversity, and antigen specificity of T cells in breastmilk and peripheral blood of lactating individuals who received SARS-CoV-2 messenger RNA (mRNA) vaccination. Relative to blood, breastmilk contained higher frequencies of T effector and central memory populations that expressed mucosal-homing markers. T cell receptor sequence overlap was limited between blood and breastmilk. Overabundant breastmilk clones were observed in all individuals, were diverse, and contained complementarity-determining regions in three sequences with known epitope specificity, including to SARS-CoV-2 spike. SARS-CoV-2 spike-specific T cell receptors were more frequent in breastmilk compared to blood and expanded in breastmilk following a 3rd mRNA vaccine dose. Our observations indicate that the lactating breast contains a distinct T cell population that can be modulated by maternal vaccination with potential implications for passive infant protection.

Successful Treatment of Prolonged, Severe Coronavirus Disease 2019 Lower Respiratory Tract Disease in a B cell Acute Lymphoblastic Leukemia Patient With an Extended Course of Remdesivir and Nirmatrelvir/Ritonavir.

A patient with B-cell acute lymphoblastic leukemia (ALL) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had persistent, progressive pneumonia with viremia after 5 months of infection despite monoclonal antibodies, intravenous (IV) remdesivir and prolonged oral steroids. Twenty days of nirmatrelvir/ritonavir and 10 days of IV remdesivir led to full recovery.

Association between ambient temperature and stroke risk in high-risk populations: a systematic review.

Background: Significant associations exist between ambient temperature and stroke risk, but results in high cardiovascular risk populations are lacking. This systemic review summarised current evidence on ambient temperature and overall stroke risk in a high cardiovascular risk population. Methods: We performed a systematic literature search across MEDLINE, Embase, PsycINFO, CINAHL, Web of Science, and GEOBASE, from inception to 3 July 2023, to identify all population-based studies. Eligible studies screened by independent reviewers recruited individuals aged 18 years and over, where minimum 80% of participants had a high cerebral vascular disease (CVD) risk profile. The primary outcomes are stroke morbidity and mortality, while the secondary outcomes are morbidity and mortality of ischaemic stroke (IS), intracranial cerebral haemorrhage (ICH), and subarachnoid haemorrhage (SH). Results: The database searches identified 9,025 articles. After removing duplicates, 7,647 articles were screened in title and abstract to identify 380 articles for full-text screening. After the full-text screening of 380 articles by two independent reviewers, 23 articles were included in the review. Conclusion: The evidence for an association between ambient temperature and stroke incidence is that lower temperatures were more likely to increase morbidity and mortality risk of both haemorrhagic and ischaemic stroke in older people. Conversely, higher ambient temperature is significantly associated with intracranial haemorrhage risk, but decreased risk with IS. Higher and lower ambient temperatures consistently increase stroke risks in patients with comorbidities of congestive heart failure and dyslipidaemia. This evidence implies the need to establish clinical guidelines for preventive intervention in patients with high stroke risks during extreme ambient temperatures.

Spike-specific T cells are enriched in breastmilk following SARS-CoV-2 mRNA vaccination.

Human breastmilk is rich in T cells; however, their specificity and function are largely unknown. We compared the phenotype, diversity, and antigen specificity of T cells in the breastmilk and peripheral blood of lactating individuals who received SARS-CoV-2 mRNA vaccination. Relative to blood, breastmilk contained higher frequencies of T effector and central memory populations that expressed mucosal-homing markers. T cell receptor (TCR) sequence overlap was limited between blood and breastmilk. Overabundan t breastmilk clones were observed in all individuals, were diverse, and contained CDR3 sequences with known epitope specificity including to SARS-CoV-2 Spike. Spike-specific TCRs were more frequent in breastmilk compared to blood and expanded in breastmilk following a third mRNA vaccine dose. Our observations indicate that the lactating breast contains a distinct T cell population that can be modulated by maternal vaccination with potential implications for infant passive protection. One-Sentence Summary: The breastmilk T cell repertoire is distinct and enriched for SARS-CoV-2 Spike-specificity after maternal mRNA vaccination.

CD8+ T cell clonotypes from prior SARS-CoV-2 infection predominate during the cellular immune response to mRNA vaccination.

Almost three years into the SARS-CoV-2 pandemic, hybrid immunity is highly prevalent worldwide and more protective than vaccination or prior infection alone. Given emerging resistance of variant strains to neutralizing antibodies (nAb), it is likely that T cells contribute to this protection. To understand how sequential SARS-CoV-2 infection and mRNA-vectored SARS-CoV-2 spike (S) vaccines affect T cell clonotype-level expansion kinetics, we identified and cross-referenced TCR sequences from thousands of S-reactive single cells against deeply sequenced peripheral blood TCR repertoires longitudinally collected from persons during COVID-19 convalescence through booster vaccination. Successive vaccinations recalled memory T cells and elicited antigen-specific T cell clonotypes not detected after infection. Vaccine-related recruitment of novel clonotypes and the expansion of S-specific clones were most strongly observed for CD8+ T cells. Severe COVID-19 illness was associated with a more diverse CD4+ T cell response to SARS-CoV-2 both prior to and after mRNA vaccination, suggesting imprinting of CD4+ T cells by severe infection. TCR sequence similarity search algorithms revealed myriad public TCR clusters correlating with human leukocyte antigen (HLA) alleles. Selected TCRs from distinct clusters functionally recognized S in the predicted HLA context, with fine viral peptide requirements differing between TCRs. Most subjects tested had S-specific T cells in the nasal mucosa after a 3rd mRNA vaccine dose. The blood and nasal T cell responses to vaccination revealed by clonal tracking were more heterogeneous than nAb boosts. Analysis of bulk and single cell TCR sequences reveals T cell kinetics and diversity at the clonotype level, without requiring prior knowledge of T cell epitopes or HLA restriction, providing a roadmap for rapid assessment of T cell responses to emerging pathogens.

Heat Stress and an Immune Challenge Influence Turkey Meat Quality, but Conspecific-Directed Pecking Behavior Does Not.

Heat stress (HS), immune challenges (IC) and pecking behavior are some of the many stressors poultry can experience in commercial settings that may affect bird welfare and meat quality after harvest. The first objective was to determine if HS or IC turkeys displayed greater negative effects on meat quality, and the second objective was to determine if the frequency of non-aggressive pecking behaviors among the birds was related to meat quality. Ninety-two, commercial male, beak-trimmed turkeys were used with a total of 15 rooms and 4-7 birds per room. Each treatment was applied for 1 week prior to harvest: the Control (CON) group had no stressors added, the HS group ambient temperature was approximately 29 °C for 120 min, and the IC group involved inoculating birds with a live vaccine for hemorrhagic enteritis virus. Birds were recorded and scored to quantify pecking behavior. Once harvested, carcasses were evaluated for feather retention force, pH, color, proximate analysis, fatty acid composition, shear force, and drip loss. Stress treatment resulted in HS breasts having the lowest protein content, and IC breasts having the lowest CIE L* values and the greatest shear force values. Pecking behavior had no impact on any meat quality attributes.

Impact of Antimicrobial Carcass Washes and Processing Techniques on Quality Attributes of Beef Frankfurters.

The objective of this study was to determine the impact of antimicrobial carcass washes on beef trim in the production of frankfurters. Twenty-four beef carcasses had different antimicrobial wash treatments (TRTs) randomly applied during the harvest procedure: 82 °C water (CON), peroxyacetic acid (PAA), or lactic acid (LA). Frankfurters were produced using carcass trim at two different batter temperature processes (PROC): 4 °C (LTP) and 21 °C (HTP). Frankfurters were analyzed for processing yield (PY), emulsion stability (ES), instrumental external and internal color (CIE L*, a*, b*), purge loss, texture, and sensory analysis. TRT had very little impact on frankfurter characteristics with a difference found in ES water and instrumental hardness (p < 0.05). PROC impacted ES water, ES fat, PY, instrumental springiness, external and internal color, sensory hardness, cohesion, and juiciness (p < 0.05). However, no TRT × PROC interactions were found to be significant (p > 0.05). These data indicate that antimicrobial carcass washes had little impact on frankfurter quality, while the processing technique impacted several frankfurter quality characteristics. This indicates that processors can impact frankfurter composition via processing techniques without concern of antimicrobial washes influencing frankfurter quality.

Methods to Measure Antibody Neutralization of Live Human Coronavirus OC43.

The human Betacoronavirus OC43 is a common cause of respiratory viral infections in adults and children. Lung infections with OC43 are associated with mortality, especially in hematopoietic stem cell transplant recipients. Neutralizing antibodies play a major role in protection against many respiratory viral infections, but to date a live viral neutralization assay for OC43 has not been described. We isolated a human monoclonal antibody (OC2) that binds to the spike protein of OC43 and neutralizes the live virus derived from the original isolate of OC43. We used this monoclonal antibody to develop and test the performance of two readily accessible in vitro assays for measuring antibody neutralization, one utilizing cytopathic effect and another utilizing an ELISA of infected cells. We used both methods to measure the neutralizing activity of the OC2 monoclonal antibody and of human plasma. These assays could prove useful for studying humoral responses to OC43 and cross-neutralization with other medically important betacoronaviruses.

Evaluation of Cell-Based and Surrogate SARS-CoV-2 Neutralization Assays.

Determinants of protective immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection require the development of well-standardized, reproducible antibody assays. This need has led to the emergence of a variety of neutralization assays. Head-to-head evaluation of different SARS-CoV-2 neutralization platforms could facilitate comparisons across studies and laboratories. Five neutralization assays were compared using 40 plasma samples from convalescent individuals with mild to moderate coronavirus disease 2019 (COVID-19): four cell-based systems using either live recombinant SARS-CoV-2 or pseudotyped viral particles created with lentivirus (LV) or vesicular stomatitis virus (VSV) packaging and one surrogate enzyme-linked immunosorbent assay (ELISA)-based test that measures inhibition of the spike protein receptor binding domain (RBD) binding its receptor human angiotensin converting enzyme 2 (hACE2). Vero cells, Vero E6 cells, HEK293T cells expressing hACE2, and TZM-bl cells expressing hACE2 and transmembrane serine protease 2 were tested. All cell-based assays showed 50% neutralizing dilution (ND50) geometric mean titers (GMTs) that were highly correlated (Pearson r = 0.81 to 0.89) and ranged within 3.4-fold. The live virus assay and LV pseudovirus assays with HEK293T/hACE2 cells showed very similar mean titers, 141 and 178, respectively. ND50 titers positively correlated with plasma IgG targeting SARS-CoV-2 spike protein and RBD (r = 0.63 to 0.89), but moderately correlated with nucleoprotein IgG (r = 0.46 to 0.73). ND80 GMTs mirrored ND50 data and showed similar correlation between assays and with IgG concentrations. The VSV pseudovirus assay and LV pseudovirus assay with HEK293T/hACE2 cells in low- and high-throughput versions were calibrated against the WHO SARS-CoV-2 IgG standard. High concordance between the outcomes of cell-based assays with live and pseudotyped virions enables valid cross-study comparison using these platforms.

Outcomes of Hematopoietic Cell Transplantation in Patients with Mixed Response to Pretransplantation Treatment of Confirmed or Suspected Invasive Fungal Infection.

Patients with hematologic malignancy or bone marrow failure are typically required to achieve radiographic improvement or stabilization of invasive fungal infection (IFI) before hematopoietic cell transplantation (HCT) owing to a concern for progression before engraftment. Refractory IFI with a mixture of improvement and progression on serial imaging (ie, mixed response) poses a clinical dilemma, because a delay in HCT may allow for a hematologic relapse or other complications. Furthermore, HCT itself may yield the immune reconstitution necessary for clearance of infection. We sought to describe the characteristics and outcomes of patients who underwent HCT with mixed response IFI. We performed a chart review of all patients who underwent HCT between 2014 and 2020 in whom imaging within 6 weeks before HCT indicated a mixed response to treatment of a diagnosed IFI. Fourteen patients had evidence of a mixed response in low-to-moderate burden of diagnosed IFI by imaging before HCT, including 9 with pulmonary aspergillosis, 2 with hepatosplenic candidiasis (1 also with aspergillosis), and 4 with pulmonary nodules of presumed fungal etiology. Five had refractory severe neutropenia at evaluation for HCT (median, 95 days). All 14 patients showed radiographic stability or improvement in imaging following engraftment; no IFI-related surgeries were required, and no IFI-related deaths occurred. For patients without relapse who underwent HCT more than 1 year earlier, 7 of 8 (88%) were alive at 1 year. Our findings suggest that low-to-moderate burden IFI with mixed response is unlikely to progress on appropriate therapy before engraftment during allogeneic HCT.

B cells, antibody-secreting cells, and virus-specific antibodies respond to herpes simplex virus 2 reactivation in skin.

Tissue-based T cells are important effectors in the prevention and control of mucosal viral infections; less is known about tissue-based B cells. We demonstrate that B cells and antibody-secreting cells (ASCs) are present in inflammatory infiltrates in skin biopsy specimens from study participants during symptomatic herpes simplex virus 2 (HSV-2) reactivation and early healing. Both CD20+ B cells, most of which are antigen inexperienced based on their coexpression of IgD, and ASCs - characterized by dense IgG RNA expression in combination with CD138, IRF4, and Blimp-1 RNA - were found to colocalize with T cells. ASCs clustered with CD4+ T cells, suggesting the potential for crosstalk. HSV-2-specific antibodies to virus surface antigens were also present in tissue and increased in concentration during HSV-2 reactivation and healing, unlike in serum, where concentrations remained static over time. B cells, ASCs, and HSV-specific antibody were rarely detected in biopsies of unaffected skin. Evaluation of samples from serial biopsies demonstrated that B cells and ASCs followed a more migratory than resident pattern of infiltration in HSV-affected genital skin, in contrast to T cells. Together, these observations suggest the presence of distinct phenotypes of B cells in HSV-affected tissue; dissecting their role in reactivation may reveal new therapeutic avenues to control these infections.