Safety and Immunogenicity of the ID93 + GLA-SE Tuberculosis Vaccine in BCG-Vaccinated Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Phase 2 Trial

INTRODUCTION

This randomized, double-blind, placebo-controlled, phase 2a trial was conducted to evaluate the safety and immunogenicity of the ID93 + glucopyranosyl lipid adjuvant (GLA)-stable emulsion (SE) vaccine in human immunodeficiency virus (HIV)-negative, previously Bacillus Calmette-Guérin (BCG)-vaccinated, and QuantiFERON-TB-negative healthy adults in South Korea.

METHODS

Adults (n = 107) with no signs or symptoms of tuberculosis were randomly assigned to receive three intramuscular injections of 2 μg ID93 + 5 μg GLA-SE, 10 μg ID93 + 5 μg GLA-SE, or 0.9% normal saline placebo on days 0, 28, and 56. For safety assessment, data on solicited adverse events (AEs), unsolicited AEs, serious AEs (SAEs), and special interest AEs were collected. Antigen-specific antibody responses were measured using serum enzyme-linked immunosorbent assay. T-cell immune responses were measured using enzyme-linked immunospot and intracellular cytokine staining.

RESULTS

No SAEs, deaths, or AEs leading to treatment discontinuation were found. The solicited local and systemic AEs observed were consistent with those previously reported. Compared with adults administered with the placebo, those administered with three intramuscular vaccine injections exhibited significantly higher antigen-specific antibody levels and Type 1 T-helper cellular immune responses.

CONCLUSION

The ID93 + GLA-SE vaccine induced antigen-specific cellular and humoral immune responses, with an acceptable safety profile in previously healthy, BCG-vaccinated, Mycobacterium tuberculosis-uninfected adult healthcare workers.

TRIAL REGISTRATION

This clinical trial was retrospectively registered on 16 January 2019 at Clinicaltrials.gov (NCT03806686).

TB Vaccines Update: is an RNA-based vaccine feasible for TB?

OBJECTIVES

Despite concerted efforts, Mycobacterium tuberculosis (M.tb), the pathogen that causes tuberculosis (TB), continues to be a burden on global health, regaining its dubious distinction in 2022 as the world's biggest infectious killer with global COVID-19 deaths steadily declining. The complex nature of M.tb, coupled with different pathogenic stages, has highlighted the need for development of novel immunization approaches to combat this ancient infectious agent. Intensive efforts over the last couple of decades have identified alternative approaches to improve upon traditional vaccines that are based on killed pathogens, live attenuated agents, or subunit recombinant antigens formulated with adjuvants. Massive funding and rapid advances in RNA-based vaccines for immunization have recently transformed the possibility of protecting global populations from viral pathogens, such as SARS-CoV-2. Similar efforts to combat bacterial pathogens such as M.tb have been significantly slower to implement.

METHODS

In this review, we discuss the application of a novel replicating RNA (repRNA)-based vaccine formulated and delivered in nanostructured lipids.

RESULTS

Our preclinical data are the first to report that RNA platforms are a viable system for TB vaccines and should be pursued with high priority M.tb antigens containing CD4+ and CD8+ T cell epitopes.

CONCLUSION

This RNA vaccine shows promise for use against intracellular bacteria such as M.tb as demonstrated by the feasibility of construction, enhanced induction of cell mediated and humoral immune responses, and improved bacterial burden outcomes in in vivo aerosol challenged preclinical TB models.

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.

An RNA-Based Vaccine Platform for Use against Mycobacterium tuberculosis

Mycobacterium tuberculosis (M.tb), a bacterial pathogen that causes tuberculosis disease (TB), exerts an extensive burden on global health. The complex nature of M.tb, coupled with different TB disease stages, has made identifying immune correlates of protection challenging and subsequently slowing vaccine candidate progress. In this work, we leveraged two delivery platforms as prophylactic vaccines to assess immunity and subsequent efficacy against low-dose and ultra-low-dose aerosol challenges with M.tb H37Rv in C57BL/6 mice. Our second-generation TB vaccine candidate ID91 was produced as a fusion protein formulated with a synthetic TLR4 agonist (glucopyranosyl lipid adjuvant in a stable emulsion) or as a novel replicating-RNA (repRNA) formulated in a nanostructured lipid carrier. Protein subunit- and RNA-based vaccines preferentially elicit cellular immune responses to different ID91 epitopes. In a single prophylactic immunization screen, both platforms reduced pulmonary bacterial burden compared to the controls. Excitingly, in prime-boost strategies, the groups that received heterologous RNA-prime, protein-boost or combination immunizations demonstrated the greatest reduction in bacterial burden and a unique humoral and cellular immune response profile. These data are the first to report that repRNA platforms are a viable system for TB vaccines and should be pursued with high-priority M.tb antigens containing CD4+ and CD8+ T-cell epitopes.

Immunogenicity and protection against Mycobacterium avium with a heterologous RNA prime and protein boost vaccine regimen

Prophylactic efficacy of two different delivery platforms for vaccination against Mycobacterium avium (M. avium) were tested in this study; a subunit and an RNA-based vaccine. The vaccine antigen, ID91, includes four mycobacterial antigens: Rv3619, Rv2389, Rv3478, and Rv1886. We have shown that ID91+GLA-SE is effective against a clinical NTM isolate, M. avium 2-151 smt. Here, we extend these results and show that a heterologous prime/boost strategy with a repRNA-ID91 (replicon RNA) followed by protein ID91+GLA-SE boost is superior to the subunit protein vaccine given as a homologous prime/boost regimen. The repRNA-ID91/ID91+GLA-SE heterologous regimen elicited a higher polyfunctional CD4+ TH1 immune response when compared to the homologous protein prime/boost regimen. More significantly, among all the vaccine regimens tested only repRNA-ID91/ID91+GLA-SE induced IFN-γ and TNF-secreting CD8+ T cells. Furthermore, the repRNA-ID91/ID91+GLA-SE vaccine strategy elicited high systemic proinflammatory cytokine responses and induced strong ID91 and an Ag85B-specific humoral antibody response a pre- and post-challenge with M. avium 2-151 smt. Finally, while all prophylactic prime/boost vaccine regimens elicited a degree of protection in beige mice, the heterologous repRNA-ID91/ID91+GLA-SE vaccine regimen provided greater pulmonary protection than the homologous protein prime/boost regimen. These data indicate that a prophylactic heterologous repRNA-ID91/ID91+GLA-SE vaccine regimen augments immunogenicity and confers protection against M. avium.

Characterizing in vivo loss of virulence of an HN878 Mycobacterium tuberculosis isolate from a genetic duplication event

The increase of global cases of drug resistant (DR) Mycobacterium tuberculosis (M.tb) is a serious problem for the tuberculosis research community and the goals to END TB by 2030. Due to the need for advancing and screening next generation therapeutics and vaccines, we aimed to design preclinical DR models of Beijing lineage M.tb HN878 strain in different mouse backgrounds. We found escalating sensitivities of morbidity due to low dose aerosol challenge (50-100 bacilli) in CB6F1, C57BL/6 and SWR mice, respectively. We also observed that pulmonary bacterial burden at morbidity endpoints correlated inversely with survival over time between mouse strains. Interestingly, with in vitro passaging and in the process of selecting individual DR mutant colonies, we observed a significant decrease in in vivo HN878 strain virulence, which correlated with the acquisition of a large genetic duplication. We confirmed that low passage infection stocks with no or low prevalence of the duplication, including stocks directly acquired from the BEI resources biorepository, retained virulence, measured by morbidity over time. These data help confirm previous reports and emphasize the importance of monitoring virulence and stock fidelity.

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.

Therapeutic efficacy against Mycobacterium tuberculosis using ID93 and liposomal adjuvant formulations

Mycobacterium tuberculosis (M.tb) has led to approximately 1.3 million deaths globally in 2020 according to the World Health Organization (WHO). More effective treatments are therefore required to prevent the transmission of M.tb. Although Bacille Calmette-Guérin (BCG), a prophylactic vaccine against M.tb, already exists, other vaccines are being developed that could help boost BCG's noted incomplete protection. This includes ID93 + GLA-SE, an adjuvanted protein vaccine which is being tested in Phase 2 clinical trials. The aim of this study was to test new lipid-based adjuvant formulations with ID93 in the context of a therapeutic vaccine, which we hypothesize would act as an adjunct to drug treatment and provide better outcomes, such as survival, than drug treatment alone. The recent success of another adjuvanted recombinant protein vaccine, M72 + AS01_E (GlaxoSmithKline Biologicals), which after 3 years provided approximately 50% efficacy against TB pulmonary disease, is paving the way for new and potentially more effective vaccines. We show that based on selected criteria, including survival, T helper 1 cytokine responses, and resident memory T cells in the lung, that a liposomal formulation of GLA with QS-21 (GLA-LSQ) combined with ID93 provided enhanced protection over drug treatment alone.

It Takes a Village: The Multifaceted Immune Response to Mycobacterium tuberculosis Infection and Vaccine-Induced Immunity

Despite co-evolving with humans for centuries and being intensely studied for decades, the immune correlates of protection against Mycobacterium tuberculosis (Mtb) have yet to be fully defined. This lapse in understanding is a major lag in the pipeline for evaluating and advancing efficacious vaccine candidates. While CD4+ T helper 1 (TH1) pro-inflammatory responses have a significant role in controlling Mtb infection, the historically narrow focus on this cell population may have eclipsed the characterization of other requisite arms of the immune system. Over the last decade, the tuberculosis (TB) research community has intentionally and intensely increased the breadth of investigation of other immune players. Here, we review mechanistic preclinical studies as well as clinical anecdotes that suggest the degree to which different cell types, such as NK cells, CD8+ T cells, γ δ T cells, and B cells, influence infection or disease prevention. Additionally, we categorically outline the observed role each major cell type plays in vaccine-induced immunity, including Mycobacterium bovis bacillus Calmette-Guérin (BCG). Novel vaccine candidates advancing through either the preclinical or clinical pipeline leverage different platforms (e.g., protein + adjuvant, vector-based, nucleic acid-based) to purposefully elicit complex immune responses, and we review those design rationales and results to date. The better we as a community understand the essential composition, magnitude, timing, and trafficking of immune responses against Mtb, the closer we are to reducing the severe disease burden and toll on human health inflicted by TB globally.

Qualification of ELISA and neutralization methodologies to measure SARS-CoV-2 humoral immunity using human clinical samples

In response to the SARS-CoV-2 pandemic many vaccines have been developed and evaluated in human clinical trials. The humoral immune response magnitude, composition and efficacy of neutralizing SARS-CoV-2 are essential endpoints for these trials. Robust assays that are reproducibly precise, linear, and specific for SARS-CoV-2 antigens would be beneficial for the vaccine pipeline. In this work we describe the methodologies and clinical qualification of three SARS-CoV-2 endpoint assays. We developed and qualified Endpoint titer ELISAs for total IgG, IgG1, IgG3, IgG4, IgM and IgA to evaluate the magnitude of specific responses to the trimeric spike (S) antigen and total IgG specific to the spike receptor binding domain (RBD) of SARS-CoV-2. We also qualified a pseudovirus neutralization assay which evaluates functional antibody titers capable of inhibiting the entry and replication of a lentivirus containing the Spike antigen of SARS-CoV-2. To complete the suite of assays we qualified a plaque reduction neutralization test (PRNT) methodology using the 2019-nCoV/USA-WA1/2020 isolate of SARS-CoV-2 to assess neutralizing titers of antibodies in plasma from normal healthy donors and convalescent COVID-19 individuals.

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Precision, Linearity, and Specificity are essential for Clinical Assay Qualification.

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Vaccine or Infection-induced humoral response magnitude can be evaluated by high-throughput ELISAs.

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Neutralization of SARS-CoV-2 is the gold-standard for in vitro vaccine efficacy evaluations.

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ELISA, pseudovirus neutralization and PRNT assays are Clinically Qualified for SARS-CoV-2 vaccine trials.

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Positive WHO control sample of 250 ABU equals 4.7 EPT for total IgG against SARS-CoV-2 trimeric spike antigen in ELISAs.

Qualification of ELISA and neutralization methodologies to measure SARS-CoV-2 humoral immunity using human clinical samples

In response to the SARS-CoV-2 pandemic many vaccines have been developed and evaluated in human clinical trials. The humoral immune response magnitude, composition and efficacy of neutralizing SARS-CoV-2 are essential endpoints for these trials. Robust assays that are reproducibly precise, linear, and specific for SARS-CoV-2 antigens would be beneficial for the vaccine pipeline. In this work we describe the methodologies and clinical qualification of three SARS-CoV-2 endpoint assays. We developed and qualified Endpoint titer ELISAs for total IgG, IgG1, IgG3, IgG4, IgM and IgA to evaluate the magnitude of specific responses to the trimeric spike (S) antigen and total IgG specific to the spike receptor binding domain (RBD) of SARS-CoV-2. We also qualified a pseudovirus neutralization assay which evaluates functional antibody titers capable of inhibiting the entry and replication of a lentivirus containing the Spike antigen of SARS-CoV-2. To complete the suite of assays we qualified a plaque reduction neutralization test (PRNT) methodology using the 2019-nCoV/USA-WA1/2020 isolate of SARS-CoV-2 to assess neutralizing titers of antibodies in plasma from normal healthy donors and convalescent COVID-19 individuals.

The relative effectiveness of two expanding bullet designs in young harp seals (Pagophilus groenlandicus): A randomised controlled field study in the Norwegian harp seal hunt

The aim of this study was to investigate the relative effectiveness of a rapidly expanding Bonded hunting bullet and an explosively expanding Varmint bullet in young harp seals (P). The study was conducted as an open, controlled and randomised parallel-group designed field trial. The animals were pre-randomised (1:1) into one explosively expanding (Varmint) and one expanding (Bonded) bullet type group, with 75 animals in each. The study sample consisted of young, weaned harp seals, 2–7 weeks of age, of both sexes, from the Greenland Sea harp seal population. The study was conducted during the regular hunt. Instantaneous death rate (IDR) and time to death (TTD) were the main variables. The observed IDR was 84 in both bullet groups. Correcting for Weather Condition Index, the IDR for the Varmint bullet was significantly higher compared to the Bonded. The mean TTD was shortest in the Varmint group, but the difference did not reach significance. Compared to the Bonded, a significantly higher total cranial damage score and bleeding intensity, and significantly lower frequencies of bullet exit wounds were detected in the Varmint group. The post mortem reflex movements caused by the Varmint bullet were significantly more powerful with longer duration and higher frequencies of clonic contractions. In conclusion, the results indicate a higher effectiveness of the Varmint bullet relative to the Bonded. The Varmint bullet may thus improve animal welfare in the hunt of young harp seals.

Subunit vaccine protects against a clinical isolate of Mycobacterium avium in wild type and immunocompromised mouse models

The nontuberculous mycobacteria (NTM) Mycobacterium avium is a clinically significant pathogen that can cause a wide range of maladies, including tuberculosis-like pulmonary disease. An immunocompromised host status, either genetically or acutely acquired, presents a large risk for progressive NTM infections. Due to this quietly emerging health threat, we evaluated the ability of a recombinant fusion protein ID91 combined with GLA-SE [glucopyranosyl lipid adjuvant, a toll like receptor 4 agonist formulated in an oil-in-water stable nano-emulsion] to confer protection in both C57BL/6 (wild type) and Beige (immunocompromised) mouse models. We optimized an aerosol challenge model using a clinical NTM isolate: M. avium 2-151 smt, observed bacterial growth kinetics, colony morphology, drug sensitivity and histopathology, characterized the influx of pulmonary immune cells, and confirmed the immunogenicity of ID91 in both mouse models. To determine prophylactic vaccine efficacy against this M. avium isolate, mice were immunized with either ID91 + GLA-SE or bacillus Calmette-Guérin (BCG). Immunocompromised Beige mice displayed a delayed influx of innate and adaptive immune cells resulting in a sustained and increased bacterial burden in the lungs and spleen compared to C57BL/6 mice. Importantly, both ID91 + GLA-SE and BCG vaccines significantly reduced pulmonary bacterial burden in both mouse strains. This work is a proof-of-concept study of subunit vaccine-induced protection against NTM.

Prophylactic efficacy against Mycobacterium tuberculosis using ID93 and lipid-based adjuvant formulations in the mouse model

An estimated 10 million people developed tuberculosis (TB) disease in 2019 which underscores the need for a vaccine that prevents disease and reduces transmission. The aim of our current studies is to characterize and test a prophylactic tuberculosis vaccine comprised of ID93, a polyprotein fusion antigen, and a liposomal formulation [including a synthetic TLR4 agonist (glucopyranosyl lipid adjuvant, GLA) and QS-21] in a preclinical mouse model of TB disease. Comparisons of the ID93+GLA-LSQ vaccines are also made to the highly characterized ID93+GLA-SE oil-in-water emulsion adjuvant, which are also included these studies. The recent success of vaccine candidate M72 combined with adjuvant AS01E (GlaxoSmithKline Biologicals) in reducing progression to active disease is promising and has renewed excitement for experimental vaccines currently in the TB vaccine pipeline. The AS01E adjuvant contains monophosphoryl lipid A (MPL) and QS-21 (a saponin) in a liposomal formulation. While AS01E has demonstrated potent adjuvant activity as a component of both approved and experimental vaccines, developing alternatives to this adjuvant system will become important to fill the high demand envisioned for future vaccine needs. Furthermore, replacement sources of potent adjuvants will help to supply the demand of a TB vaccine [almost one-quarter of the world's population are estimated to have latent Mycobacterium tuberculosis (Mtb) according to the WHO 2019 global TB report], addressing (a) cost of goods, (b) supply of goods, and (c) improved efficacy of subunit vaccines against Mtb. We show that both ID93+GLA-SE (containing an emulsion adjuvant) and ID93+GLA-LSQ (containing a liposomal adjuvant) induce ID93-specific TH1 cellular immunity including CD4+CD44+ T cells expressing IFNγ, TNF, and IL-2 (using flow cytometry and intracellular cytokine staining) and vaccine-specific IgG2 antibody responses (using an ELISA). In addition, both ID93+GLA-SE and ID93+GLA-LSQ effectively decrease the bacterial load within the lungs of mice infected with Mtb. Formulations based on this liposomal adjuvant formulation may provide an alternative to AS01 adjuvant systems.

Long-term protective efficacy with a BCG-prime ID93/GLA-SE boost regimen against the hyper-virulent Mycobacterium tuberculosis strain K in a mouse model

Since ID93/GLA-SE was developed as a targeted BCG-prime booster vaccine, in the present study, we evaluated the protective efficacy of ID93/GLA-SE as a boost to a BCG-prime against the hypervirulent Mycobacterium tuberculosis (Mtb) K challenge to provide further information on the development and application of this vaccine candidate. Boosting BCG with the ID93/GLA-SE vaccine significantly reduced bacterial burden at 16 weeks post-challenge while the BCG vaccine alone did not confer significant protection against Mtb K. The pathological analysis of the lung from the challenged mice also showed the remarkably protective boosting effect of ID93/GLA-SE on BCG-immunised animals. Moreover, qualitative and quantitative analysis of the immune responses following ID93/GLA-SE-immunisation demonstrated that ID93/GLA-SE was able to elicit robust and sustained Th1-biased antigen-specific multifunctional CD4⁺ T-cell responses up to 16 weeks post-challenge as well as a high magnitude of an antigen-specific IgG response. Our findings demonstrate that the ID93/GLA-SE vaccine candidate given as a BCG-prime boost regimen confers a high level of long-term protection against the hypervirulent Mtb Beijing infection. These findings will provide further and more feasible validation for the potential utility of this vaccine candidate particularly in East-Asian countries, with the predominance of the Beijing genotype, after BCG vaccination.

Subunit vaccine candidate with adjuvant confers protection against clinical Mycobacterium avium in wild type and immunocompromised mouse models

Nontuberculous mycobacteria (NTM) are a group of 170 species of mycobacteria that are steadily increasing in incidence and prevalence. NTM cause a significant amount of morbidity and mortality and overtake Mycobacterium tuberculosis in prevalence in certain regions of the world, including the United States. M. avium, a clinically significant NTM, is known to cause a tuberculosis-like pulmonary disease that is often difficult to treat. Due to this quietly emerging health threat, we evaluated the ability of a subunit vaccine (ID91) with the Toll-like receptor agonist glucopyranosyl lipid adjuvant formulated in an oil-in-water stable nano-emulsion (GLA-SE) to confer protection in both the C57BL/6 (wild type) and Beige (immunocompromised) mouse models. We first established a challenge model with a low dose aerosol of the virulent clinical isolate M. avium 2–151 smt and monitored bacterial burden and immune responses to infection over time. Next, cohorts of mice immunized prophylactically with ID91+GLA-SE or bacillus Calmette–Guérin (BCG) were subsequently challenged with M. avium 2–151 smt. Not surprisingly, the immunocompromised Beige mice sustained a larger bacterial burden in the lungs and spleen compared to C57BL/6 mice regardless of treatment. However, both ID91+GLA-SE and BCG significantly reduced pulmonary bacterial burden in both models. Variable innate and adaptive pulmonary immune response kinetics in C57BL/6 and Beige mice in response to M. avium 2–151 smt infection were observed. This work demonstrates the first proof-of-concept study that a subunit vaccine candidate (ID91+GLA-SE) confers prophylactic protection against NTM and suggests further vaccine development may help reduce the burden of disease.

The complexities and challenges of preventing and treating nontuberculous mycobacterial diseases

Seemingly innocuous nontuberculous mycobacteria (NTM) species, classified by their slow or rapid growth rates, can cause a wide range of illnesses, from skin ulceration to severe pulmonary and disseminated disease. Despite their worldwide prevalence and significant disease burden, NTM do not garner the same financial or research focus as Mycobacterium tuberculosis. In this review, we outline the most abundant of over 170 NTM species and inadequacies of diagnostics and treatments and weigh the advantages and disadvantages of currently available in vivo animal models of NTM. In order to effectively combat this group of mycobacteria, more research focused on appropriate animal models of infection, screening of chemotherapeutic compounds, and development of anti-NTM vaccines and diagnostics is urgently needed.

Memory CD4+ T cells enhance B-cell responses to drifting influenza immunization

Influenza A annually infects 5-10% of the world's human population resulting in one million deaths. Influenza causes annual epidemics and reinfects previously exposed individuals because of antigenic drift in the glycoprotein hemagglutinin. Due to antigenic drift, the immune system is simultaneously exposed to novel and conserved parts of the influenza virus via vaccination and/or infection throughout life. Preexisting immunity has long been known to augment subsequent hemagglutination inhibitory antibody (hAb) responses. However, the preexisting immunological contributors that influence hAb responses are not understood. Therefore, we adapted and developed sequential infection and immunization mouse models using drifted influenza strains to show that MHC Class II haplotype and T-cell reactivity influences subsequent hAb responses. We found that CB6F1 mice infected with A/CA followed by immunization with A/PR8 have increased hAb responses to A/PR8 compared to C57BL/6 mice. Increased hAb responses in CB6F1 mice were CD4⁺  T-cell and B-cell dependent and corresponded to increased germinal center A/PR8-specific B and T-follicular helper cells. These results suggest conserved MHC Class II restricted epitopes within HA are essential for B cells to respond to drifting influenza and could be leveraged to boost hAb responses.

Enhanced Anti-Mycobacterium tuberculosis Immunity over Time with Combined Drug and Immunotherapy Treatment

It is estimated that one third of the world’s population is infected with Mycobacterium tuberculosis (Mtb). This astounding statistic, in combination with costly and lengthy treatment regimens make the development of therapeutic vaccines paramount for controlling the global burden of tuberculosis. Unlike prophylactic vaccination, therapeutic immunization relies on the natural pulmonary infection with Mtb as the mucosal prime that directs boost responses back to the lung. The purpose of this work was to determine the protection and safety profile over time following therapeutic administration of our lead Mtb vaccine candidate, ID93 with a synthetic TLR4 agonist (glucopyranosyl lipid adjuvant in a stable emulsion (GLA-SE)), in combination with rifampicin, isoniazid, and pyrazinamide (RHZ) drug treatment. We assessed the host inflammatory immune responses and lung pathology 7–22 weeks post infection, and determined the therapeutic efficacy of combined treatment by enumeration of the bacterial load and survival in the SWR/J mouse model. We show that drug treatment alone, or with immunotherapy, tempered the inflammatory responses measured in brochoalveolar lavage fluid and plasma compared to untreated cohorts. RHZ combined with therapeutic immunizations significantly enhanced TH1-type cytokine responses in the lung over time, corresponding to decreased pulmonary pathology evidenced by a significant decrease in the percentage of lung lesions and destructive lung inflammation. These data suggest that bacterial burden assessment alone may miss important correlates of lung architecture that directly contribute to therapeutic vaccine efficacy in the preclinical mouse model. We also confirmed our previous finding that in combination with antibiotics therapeutic immunizations provide an additive survival advantage. Moreover, therapeutic immunizations with ID93/GLA-SE induced differential T cell immune responses over the course of infection that correlated with periods of enhanced bacterial control over that of drug treatment alone. Here we advance the immunotherapy model and investigate reliable correlates of protection and Mtb control.

Use of GLA-nanoalum as an effective adjuvant for a therapeutic ID93 TB vaccine

Tuberculosis (TB) caused by the intracellular bacterium Mycobacterium tuberculosis (Mtb) reportedly killed 1.3 million people in 2016 and is the leading cause of death caused by a single infectious organism. Increasingly worrisome is the ability of Mtb to develop extensive drug resistance. According to the 2017 WHO global TB report, there were 600,000 new rifampicin-resistant cases in 2016, and almost half a million cases with multiple drug resistant (MDR) TB. The development of new host-targeted therapeutic strategies that prevent the outgrowth of resistant mutants and/or modulate the immune response to combat Mtb infection and/or reduce disease pathology is one solution to prevent the generation of antibacterial resistance and treat drug resistant (DR)-TB. Here we evaluate a novel nanoalum adjuvant formulation containing a synthetic TLR4 agonist, glucopyranosyl lipid adjuvant (GLA), with our clinical ID93 protein as an immunotherapeutic vaccine. We show that immunotherapy with ID93+GLA-nanoalum is effective against Mtb when given as an adjunct to drug treatment in a mouse TB therapy model.

Improved Immune Responses in Young and Aged Mice with Adjuvanted Vaccines against H1N1 Influenza Infection

Elderly people are at high risk for influenza-related morbidity and mortality due to progressive immunosenescence. While toll-like receptor (TLR) agonist containing adjuvants, and other adjuvants, have been shown to enhance influenza vaccine-induced protective responses, the mechanisms underlying how these adjuvanted vaccines could benefit the elderly remain elusive. Here, we show that a split H1N1 influenza vaccine (sH1N1) combined with a TLR4 agonist, glucopyranosyl lipid adjuvant formulated in a stable oil-in-water emulsion (GLA-SE), boosts IgG2c:IgG1 ratios, enhances hemagglutination inhibition (HAI) titers, and increases protection in aged mice. We find that all adjuvanted sH1N1 vaccines tested were able to protect both young and aged mice from lethal A/H1N1/California/4/2009 virus challenge after two immunizations compared to vaccine alone. We show that GLA-SE combined with sH1N1, however, also provides enhanced protection from morbidity in aged mice given one immunization (based on change in weight percentage). While the GLA-SE-adjuvanted sH1N1 vaccine promotes the generation of cytokine-producing T helper 1 cells, germinal center B cells, and long-lived bone marrow plasma cells in young mice, these responses were muted in aged mice. Differential in vitro responses, dependent on age, were also observed from mouse-derived bone marrow-derived dendritic cells and lung homogenates following stimulation with adjuvants, including GLA-SE. Besides enhanced HAI titers, additional protective factors elicited with sH1N1 + GLA-SE in young mice were observed, including (a) rapid reduction of viral titers in the lung, (b) prevention of excessive lung inflammation, and (c) homeostatic maintenance of alveolar macrophages (AMs) following H1N1 infection. Collectively, our results provide insight into mechanisms of adjuvant-mediated immune protection in the young and elderly.

Arbuscular mycorrhizas are present on Spitsbergen

A previous study of 76 plant species on Spitsbergen in the High Arctic concluded that structures resembling arbuscular mycorrhizas were absent from roots. Here, we report a survey examining the roots of 13 grass and forb species collected from 12 sites on the island for arbuscular mycorrhizal (AM) colonisation. Of the 102 individuals collected, we recorded AM endophytes in the roots of 41 plants of 11 species (Alopecurus ovatus, Deschampsia alpina, Festuca rubra ssp. richardsonii, putative viviparous hybrids of Poa arctica and Poa pratensis, Poa arctica ssp. arctica, Trisetum spicatum, Coptidium spitsbergense, Ranunculus nivalis, Ranunculus pygmaeus, Ranunculus sulphureus and Taraxacum arcticum) sampled from 10 sites. Both coarse AM endophyte, with hyphae of 5-10 μm width, vesicles and occasional arbuscules, and fine endophyte, consisting of hyphae of 1-3 μm width and sparse arbuscules, were recorded in roots. Coarse AM hyphae, vesicles, arbuscules and fine endophyte hyphae occupied 1.0-30.7, 0.8-18.3, 0.7-11.9 and 0.7-12.8% of the root lengths of colonised plants, respectively. Principal component analysis indicated no associations between the abundances of AM structures in roots and edaphic factors. We conclude that the AM symbiosis is present in grass and forb roots on Spitsbergen.

Metabolic reprogramming and apoptosis sensitivity: Defining the contours of a T cell response

An effective adaptive immune response hinges on the rapid clonal expansion of T cells in response to antigen. The sensitivity of these T cells to programmed cell death (i.e. apoptosis) is carefully calibrated at various stages to ensure a robust yet measured reaction that resolves without inflicting unintended damage to host tissues. To meet bioenergetic demands associated with vigorous proliferation, acquisition of effector functions, and memory formation, T cells also undergo dynamic changes in their metabolism at every stage of this response. In this review, we focus on relatively recent studies that illuminate intimate links between metabolic programs and apoptosis sensitivity in T cells. We then examine how these connections ultimately influence T cell survival and function within the metabolically taxing environs of the tumor microenvironment.

Differential cytokine withdrawal-induced death sensitivity of effector T cells derived from distinct human CD8+ memory subsets

CD8⁺ central memory (CM) and effector memory (EM) T-cell subsets exhibit well-established differences in proliferative and protective capacity after infectious challenge. However, their relative sensitivity to apoptosis has been largely overlooked, despite the importance of programmed cell death in regulating effector T-cell homeostasis. Here we demonstrate that primary human effector T cells derived from the CD8⁺ EM subset exhibit significantly higher sensitivity to cytokine withdrawal-induced cell death (CWID), a critical intrinsic apoptosis program responsible for culling cells once an infection is cleared and interleukin-2 (IL-2) levels diminish. Interestingly, we found no differences in the expression of IL-2 or IL-2 receptor components in cells originating from either subset. Relative to CM-derived effectors, however, EM-derived T cells displayed more mitochondrial instability and greater caspase activity. Indeed, we found that heightened CWID sensitivity in EM-derived effectors coincided with higher expression of the pro-apoptotic Bcl-2 family protein BIM, both at steady state and with de novo induction following withdrawal of exogenous IL-2. These data point to ‘imprinted’ differences in BIM protein regulation, preserved by CD8⁺ CM and EM progeny, which govern their relative sensitivity to CWID. In addition, we detected a burst of autophagy after IL-2 withdrawal, which was better maintained in CM-derived T cells. Both subsets showed increased, equivalent CWID sensitivity upon treatment with autophagy inhibitors, suggesting sustained autophagy could preferentially protect CM-derived T cells from apoptosis. These findings offer new insight into how CM CD8⁺ T cells display superior effector cell expansion and more persistent memory responses in vivo relative to EM-derived T cells, based in part on decreased CWID sensitivity.

Inhibition of diacylglycerol kinase α restores restimulation-induced cell death and reduces immunopathology in XLP-1

X-linked lymphoproliferative disease (XLP-1) is an often-fatal primary immunodeficiency associated with the exuberant expansion of activated CD8(+) T cells after Epstein-Barr virus (EBV) infection. XLP-1 is caused by defects in signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), an adaptor protein that modulates T cell receptor (TCR)-induced signaling. SAP-deficient T cells exhibit impaired TCR restimulation-induced cell death (RICD) and diminished TCR-induced inhibition of diacylglycerol kinase α (DGKα), leading to increased diacylglycerol metabolism and decreased signaling through Ras and PKCθ (protein kinase Cθ). We show that down-regulation of DGKα activity in SAP-deficient T cells restores diacylglycerol signaling at the immune synapse and rescues RICD via induction of the proapoptotic proteins NUR77 and NOR1. Pharmacological inhibition of DGKα prevents the excessive CD8(+) T cell expansion and interferon-γ production that occur in SAP-deficient mice after lymphocytic choriomeningitis virus infection without impairing lytic activity. Collectively, these data highlight DGKα as a viable therapeutic target to reverse the life-threatening EBV-associated immunopathology that occurs in XLP-1 patients.

Sensitivity to Restimulation-Induced Cell Death Is Linked to Glycolytic Metabolism in Human T Cells

Restimulation-induced cell death (RICD) regulates immune responses by restraining effector T cell expansion and limiting nonspecific damage to the host. RICD is triggered by re-engagement of the TCR on a cycling effector T cell, resulting in apoptosis. It remains unclear how RICD sensitivity is calibrated in T cells derived from different individuals or subsets. In this study we show that aerobic glycolysis strongly correlates with RICD sensitivity in human CD8⁺ effector T cells. Reducing glycolytic activity or glucose availability rendered effector T cells significantly less sensitive to RICD. We found that active glycolysis specifically facilitates the induction of proapoptotic Fas ligand upon TCR restimulation, accounting for enhanced RICD sensitivity in highly glycolytic T cells. Collectively, these data indicate that RICD susceptibility is linked to metabolic reprogramming, and that switching back to metabolic quiescence may help shield T cells from RICD as they transition into the memory pool.

Sensitivity to restimulation-induced cell death is linked to glycolytic metabolism in human T cells

Restimulation-induced cell death (RICD) helps to regulate immune responses by setting an upper threshold for effector T cell expansion and limiting nonspecific damage to the host. RICD is triggered by re-engagement of the T cell receptor (TCR) on a cycling, activated T cell, resulting in apoptosis. However, it remains unclear how RICD sensitivity is calibrated in T cells derived from different individuals and subsets. As effector T cells expand and become responsive to RICD, they have also switched from a quiescent metabolic state into active aerobic glycolysis (Warburg effect). We hypothesized that in addition to facilitating proliferation and effector function, metabolic programming directly influences RICD sensitivity. We found that secretion of L-lactate, the end product of glycolysis, positively correlated with greater RICD sensitivity in CD8+ effector T cells from different human donors. Strikingly, replacing glucose in culture media for galactose, which results in almost exclusive use of oxidative phosphorylation (OXPHOS), rendered T cells significantly less sensitive to RICD. Consistent with this, blocking glycolysis with 2-deoxy-glucose (2-DG) significantly reduced RICD sensitivity, while inhibiting OXPHOS increased RICD sensitivity. Glycolysis promoted RICD sensitivity in part through mTOR signaling. Moreover, we found that active glycolysis facilitated induction of pro-apoptotic effector molecules like Fas ligand upon TCR restimulation, which was blocked with 2-DG treatment. Collectively, these data suggest that RICD susceptibility is dependent on glycolytic metabolism in effector T cells, and that switching back to OXPHOS may help shield cells transitioning into the memory pool from RICD.

Differential apoptosis sensitivity of human effector CD8+ T cells derived from central versus effector memory subsets in response to IL-2 withdrawal

CD8+ central memory (CM) and effector memory (EM) T cell subsets exhibit well-established differences in proliferative and protective capacity after infectious challenge. However, their relative sensitivity to apoptosis has been largely overlooked, despite the importance of programmed cell death in regulating effector T cell homeostasis. Here we demonstrate that primary human effector T cells derived from the CD8+ EM subset exhibit significantly higher sensitivity to cytokine withdrawal induced cell death (CWID), a critical intrinsic apoptosis program responsible for culling cells once an infection is cleared and interleukin-2 (IL-2) levels diminish. Interestingly, we found no differences in the expression of IL-2 or IL-2 receptor components in cells originating from either subset. Relative to CM-derived effectors, however, EM-derived T cells display more mitochondrial instability and greater basal caspase activation. Indeed, we found that heightened CWID sensitivity in EM-derived effectors is linked to higher expression of the pro-apoptotic Bcl-2 family protein BIM, both at steady state and with de novo induction following withdrawal of exogenous IL-2. These data point to “imprinted” differences in BIM protein regulation preserved between CD8+ CM and EM progeny that govern their relative sensitivity to CWID. These findings offer new insight into why CM-derived T cells display superior effector cell expansion and more persistent memory responses in vivo relative to EM-derived T cells, based on differential apoptosis sensitivity.

SAP facilitates recruitment and activation of LCK at NTB-A receptors during restimulation-induced cell death

Upon TCR restimulation, activated, cycling T cells can undergo a self-regulatory form of apoptosis known as restimulation-induced cell death (RICD). We previously demonstrated that RICD is impaired in T cells from patients with X-linked lymphoproliferative disease, which lack SLAM-associated protein (SAP) expression. Both SAP and the specific SLAM receptor NK, T, and B cell Ag (NTB-A) are required for RICD, but the mechanism by which these molecules promote a strong, proapoptotic signal through the TCR remains unclear. In this article, we show that the Src-family kinase LCK, but not FYN, associates with NTB-A in activated human T cells. This association increased after TCR restimulation in a SAP-dependent manner, requiring both immunoreceptor tyrosine-based switch motifs in the NTB-A cytoplasmic tail. Both NTB-A-associated LCK phosphorylation and kinase activity were enhanced in restimulated T cells, amplifying proximal TCR signaling. In contrast, TCR-induced LCK association with NTB-A, as well as phosphorylation and kinase activity, was reduced in T cells from patients with X-linked lymphoproliferative disease or normal T cells transfected with SAP-specific small interfering RNA, consistent with RICD resistance. Collectively, our data reveal how SAP nucleates a previously unknown signaling complex involving NTB-A and LCK to potentiate RICD of activated human T cells.

Prevalence of Dirofilaria immitis (Spirurida: Onchocercidae) infection in Aedes, Culex, and Culiseta mosquitoes from north San Joaquin Valley, CA

Canine heartworm is one of the most serious infections primarily affecting domestic dogs but will also infect cats and wild canids. To evaluate the potential of mosquitoes as vectors of dog heartworm, Dirofilaria immitis (Leidy) in San Joaquin County, CA, we collected mosquitoes in 2011 and analyzed for infection with heartworm by using polymerase chain reaction. Of 3,000 mosquito pools (total number of specimens = 36,554), D. immitis DNA was detected in 97 pools of seven species, and the overall minimum infection rate (MIR) for all mosquito species was 2.69: Culex pipiens L. (n = 40; MIR = 3.66), Culex tarsalis Coquillett (n = 25; MIR = 1.89), Culiseta incidens (Thomson) (n = 11; MIR = 2.81), Aedes vexans (Meigen) (n = 7; MIR = 2.18), Aedes melanimon Dyar (n = 5; MIR = 4.64), Culex erythrothorax Dyar (n = 5; MIR = 3.96), and Culiseta inornata (Williston) (n = 4; MIR = 2.65). Cx. pipiens and Cx. tarsalis had the highest number of D. immitis infections and collectively accounted for 67% of all positive pools. Ae. melanimon, Ae. vexans, and Cx. erythrothorax were found to be infected with D. immitis only in rural and agriculture areas, whereas infections in other species were identified in rural and agriculture areas, and urban and residential settings. The majority of positive pools were identified from June through November and peaked during August through October. This is the first report of D. immitis infection in Ae. melanimon, Cx. erythrothorax, Cx. tarsalis, Cs. incidens, and Cs. inornata. The frequent detection of D. immitis in field-collected Cx. pipiens and Cx. tarsalis in concert with their seasonal abundance and widespread distribution suggest a central role for these species in dog heartworm transmission. Other species, including Ae. vexans, Ae. melanimon, Cs. incidens, Cs. inornata, and Cx. erythrothorax, may play a secondary role in transmission.

A comprehensive, model-based review of vaccine and repeat infection trials for filariasis

SUMMARY Filarial worms cause highly morbid diseases such as elephantiasis and river blindness. Since the 1940s, researchers have conducted vaccine trials in 27 different animal models of filariasis. Although no vaccine trial in a permissive model of filariasis has provided sterilizing immunity, great strides have been made toward developing vaccines that could block transmission, decrease pathological sequelae, or decrease susceptibility to infection. In this review, we have organized, to the best of our ability, all published filaria vaccine trials and reviewed them in the context of the animal models used. Additionally, we provide information on the life cycle, disease phenotype, concomitant immunity, and natural immunity during primary and secondary infections for 24 different filaria models.

Particle fluxes above forests: observations, methodological considerations and method comparisons

This paper reports a study designed to test, evaluate and compare micro-meteorological methods for determining the particle number flux above forest canopies. Half-hour average particle number fluxes above a representative broad-leaved forest in Denmark derived using eddy covariance range from -7x10(7) m(-2) s(-1) (1st percentile) to 5x10(7) m(-2) s(-1) (99th percentile), and have a median value of -1.6x10(6) m(-2) s(-1). The statistical uncertainties associated with the particle number flux estimates are larger than those for momentum fluxes and imply that in this data set approximately half of the particle number fluxes are not statistically different to zero. Particle number fluxes from relaxed eddy accumulation (REA) and eddy covariance are highly correlated and of almost identical magnitude. Flux estimates from the co-spectral and dissipation methods are also correlated with those from eddy covariance but exhibit higher absolute magnitude of fluxes.

Identifying the European fossil fuel plumes in the atmosphere over the Northeast Atlantic Region through isotopic observations and numerical modelling

As part of the Danish NEAREX project the origin and variability of anthropogenic atmospheric CO(2) over the Northeast Atlantic Region (NEAR) has been studied. The project consisted of a combination of experimental and modelling activities. Local volunteers operated CO(2) sampling stations, built at University of Copenhagen, for (14)C analysis at four locations (East Denmark, Shetland Isles, Faroe Isles and Iceland). The samples were only collected during winter periods of south-easterly winds in an attempt to trace air enriched in fossil-fuel derived CO(2) due to combustion of fossil fuels within European countries. In order to study the transport and concentration fields over the region in detail, a three-dimensional Eulerian hemispheric air pollution model has been extended to include the main anthropogenic sources for atmospheric CO(2). During the project period (1998-2001) only a few episodes of transport from Central Europe towards NEAR arose, which makes the data set for the evaluation of the method sparse. The analysed samples indicate that the signal for fossil CO(2), as expected, is largest (up to 3.7+/-0.4% fossil CO(2)) at the Danish location closest to the European emissions areas and much weaker (up to approximately 1.5+/-0.6% fossil CO(2)) at the most remote location. As the anthropogenic signal is weak in the clean atmosphere over NEAR these numbers will, however, be very sensitive to the assumed background (14)CO(2) activity and the precision of the measurements. The model simulations include the interplay between the driving processes from the emission into the boundary layer and the following horizontal/vertical mixing and atmospheric transport and are used to analyse the meteorological conditions leading to the observed events of high fossil CO(2) over NEAR. This information about the history of the air masses is essential if an observed signal is to be utilised for identifying and quantifying sources for fossil CO(2).

Buffer zones as a sink for sediment and phosphorus between the field and stream: Danish field experiences

Rill erosion, surface runoff and storage of sediment and phosphorus in buffer zones were investigated during three winters on ca. 140 arable field slope units in twenty places in Denmark covering all landscape types, climate gradients and dominant soil types. The dominant soils are Alfisols and Spodosols, with textural composition typically ranging from sand to loam. The average slope is 7% (range: 2-20%) and median buffer zone width was 8.3 m (range: 0.6-125 m). The geometric mean annual rill erosion was 0.33 m3 ha(-1) equalling to 495 kg sediment ha(-1) and 0.25 kg P ha(-1). The deposition of sediment on the field, in the buffer zone and delivery of soil to the stream was surveyed within the 140 slope units following three winters. Deposition of sediment in the buffer zone was observed in 31% (1997/98), 31% (1998/99) and 29% (1999/2000) of the slope units. Delivery of soil across the edge of the stream was observed in 23% (1997/98), 17% (1998/99) and 25% (1999/2000) of the 140 slope units. Median dissolved P concentration in surface runoff was 0.18 mg Pl(-1) (range: 0.029-16.294 mg Pl(-1)). A probability model was developed to predict the efficiency of different widths of buffer zones.

[Diluted injectable quinine in the intramuscular and intrarectal route: comparative efficacity and tolerance in malaria treatment for children ]

The intramuscular (i.m.) route is generally used for treatment of childhood falciparum malaria in outlying health care units in Togo. The purpose of this randomized therapeutic trial was to compare the efficacy and tolerance of diluted injectable quinine administered by the i.m. versus intrarectal (IR) route. A total of 64 children ranging in age from 8 months to 15 years were treated, i.e. 32 for each administration route. All children presented uncomplicated falciparum malaria in association with vomiting in 30 cases, a single unrecurring seizure with postictal coma lasting less than 30 minutes in 25 patients, or prostration without neurological manifestations in 9. Injectable quinimax (an association of cinchona alkaloids) was diluted to a concentration of 60 mg base/ml for i.m. injection into the thigh and 30 mg base/ml for use by the IR route. Administration was performed every 12 hours for 72 hours at a dose of 12.5 mg/kg for patients in the i.m. group or at a dose of 15 mg/kg in the IR group. The anus and lower rectal mucosa were examined using an anal valve before and after treatment using the IR route. Analysis of mean temperature curves demonstrated no significant difference between the clinical effectiveness of quinimax administered by the i.m. versus IR route (p > 0.05). Similar effect were also observed on parasitemia which disappeared completely in all patients by the end of the 72-hour treatment. The main problems were insufficient product retention requiring re-administration in 25% of patients in IR group and residual pain at the injection site in 12.5% of patients in the i.m. group. Endoscopic examination revealed no evidence of ulceration or necrosis of the anorectal mucosa. These findings indicate that administration of diluted injectable quinine by IR route is an effective, well-tolerated alternative for treatment of childhood falciparum malaria. It should be used preferentially in outlying health care units in patients presenting severe malaria pending transfer to an hospital, or signs of "intermediate severity" such as hyperpyrexia, hyperparasitemia, unrepeated seizure, or intensive vomiting.

Treatment of femoral shaft fractures with Grosse-Kempf intramedullary nail

Ninety consecutive femoral shaft fractures in 87 patients treated by reamed Grosse-Kempf intramedullary nailing were reviewed. The median observation time was 45 months. The functional results were excellent or good in 82% of the fractures, fair in 16%, and poor in 2%. Four non-unions and two superficial infections were observed. Leg shortening of more than 2 cm was recorded in 2 patients. Rotatory malalignment exceeded more than 15 degrees in 2 patients. We conclude that reamed Grosse-Kempf intramedullary nailing is an excellent treatment for femoral shaft fractures. Although this study represents the first period during which we used the nail, the number of complications was acceptable.

[Inhaled budesonide versus intramuscular dexamethasone in the treatment of pseudo-croup]

We randomised 59 children hospitalized for croup to treatment with either inhaled budesonide or injected dexamethasone. Group A were treated with two inhalations of 1000 micrograms budesonide and group B received dexamethasone 0.6 mg/kg intramuscularly. We used a modified Westley-score, based on chest-wall retractions, barking cough, respiratory frequency and stridor. The children was aged three months to six years (mean 20 months). Three hours after the first treatment there was significant improvement in score amongst all children (p < 0.001), but no difference between the two groups (p < 0.20). Six and 12 hours after the first treatment there were significantly better clinical scores in group B (p = 0.001, p = 0.0004). Based on this study we recommend dexamethasone 0.6 mg/kg intramuscularly for children to be treated for croup.

Sports injuries in school-aged children. A study of traumatologic and socioeconomic outcome

In this Danish study we attempted to identify the socioeconomic consequences of sports injuries in children. A total of 1320 children, 650 boys and 670 girls, aged 6-17, completed questionnaires covering the period from the injury to recovery. The incidence rate was 74 per 1000 per year. The hospitalization rate was 4.1%. Due to the injury 37.2% of the children were absent from school for an average of 1.2 days (range 0-60 days), resulting in 1598 days' absence from school. Most of the children were injured during training (34.7%) or competition (22.6%). The other injuries occurred during recreational sporting activities (32.0%) or at school (10.7%). Fifty-four percent were absent from training or games, on average 6.0 times (range 0-99), with a total loss of 7897 training sessions. Fifteen percent of the parents were absent from work, on average for 2.2 days. Two hundred and nineteen children were absent from an after-school job, for an average of 8.6 days. The total loss was 1896 working days. The study shows that the socioeconomic consequences of sports injuries in children are a complex consisting of different parts and that the injuries had a substantial impact on the functional and social status of the children and their families.

The epidemiology of sports injuries in school-aged children

In the 5-year-period 1988-1992, 6096 children aged 6-17 (54.5% boys and 45.5% girls) were treated at the Emergency Department at Esbjerg Central Hospital after having sustained a sports injury. The data were registered according to the European Home- and Leisure-Accident Surveillance System (EHLASS) protocol. We found a total incidence rate in the municipality of Esbjerg of 73.3 per 1000 per year. Boys were most often injured in soccer, skateboard, handball, gymnastics and basketball, and girls in handball, horse-riding, gymnastics, basketball and roller-skating. The types of injuries were contusions 37.1%, fractures 22.0%, sprains 24.8%, wounds 9.5%, strains 5.0% and luxations 1.4%. The hospitalization rate was 3.8%. Compared to other studies the total incidence rate was high.

[It is not always necessary to establish a "first aid station" at mass gatherings. Cutty Sark Tallships Race 1993]

Previous studies from outdoor music festivals have recommended medical service facilities at first-aid stations. The Cutty Sark Tallships Race was a large outdoor event that took place over four days in Esbjerg harbour with about 500,000 participants and spectators. A total of 68 patients were treated, 28 in the first-aid station at the harbour and 40 at the nearby located hospital. The disease and injuries presented were not severe. The orthopaedic casualties dominated (82%), wounds, contusions and fractures being the most common ones. Only seven casualties were related to alcohol abuse. No casualties were related to drug abuse. The economic expense was estimated to DKK 14,676. Thus, at outdoor mass gatherings of a nature like the Cutty Sark Tallships Race, located near a hospital, first-aid stations are not necessary.

Paradoxical effects of bleomycin and heavy water (D2O) in mice

Bleomycin (BLM) lacks many side effects of other cytostatic drugs. Pulmonary toxicity is the major dose-limiting effect of BLM. This is based in part on generation of free radicals. It is conceivable that deuterium in body fluids lessens the production of free radicals, thus preventing or diminishing the morphologic expression of pulmonary BLM toxicity. We therefore studied the effect of moderate deuteration of body fluids on BLM-induced lung damage in BALB/c-mice. In addition to conventional histopathological methods, we used a vertical sectioning design for stereological estimation of pulmonary volumes and surface areas. BLM (low/medium/high dose: 25/50/75 IU/kg body weight) was injected i.p. once a week for 6 weeks. Half the mice drank deuterated water before, during and after BLM treatment. Three weeks after the last injection, the lungs were fixed by airway instillation. Deuterated animals treated with BLM lacked signs of irreversible BLM-induced pulmonary damage. Conversely, focal sub-pleural fibrosis and fibrosing alveolitis were present in BLM-treated mice drinking tap water. Deuterated mice had stereological values for almost all lung parameters that were lower than in non-deuterated mice. The organ-specific advantage of deuteration was offset by marked enhancement of systemic toxicity of BLM. We conclude that (1) moderate concentrations of deuterium may prevent the development of fibrosing alveolitis in BLM-treated mice, possibly by reducing proliferation of alveolar fibroblasts, and, less probably, by impairing generation or enhancing capture of free radicals; (2) the toxicity of BLM was enhanced by ingestion of deuterium, resulting in morphological liver alterations and increased mortality.

Fluctuations of visual field interpretation related to cluster and scotoma analysis by one interpreter

A total of 189 numerical printouts of the visual fields of 189 eyes of individuals either suspected of or verified as having glaucoma and displaying varying degrees of glaucomatous visual field damage were analyzed by one expert interpreter. The amount of clusters (or scotomas) was counted and delineated in each visual field under both a more stringent and a more liberal criterion. The interpretations of the visual fields differed significantly in both groups, as did the subjective certainty the interpreter allotted to his assessment. In the group of certain decisions, only 144 defects were assessed as opposed to 364 when a more stringent rather than a more liberal criterion was adopted. In uncertain cases, a reverse trend was observed, since only 11 as opposed to 324 defects were assessed when a more liberal rather than a more stringent criterion was adopted. Both trends may be explained by an increase in sensitivity at the expense of specificity (i.e., a change in the receiver-operating characteristic of the expert when the latter is pressed to change the criterion in a subjective cluster or scotoma assessment task). The ambiguity of the task and the difference in the criterion adopted by the interpreter significantly influences the assessment of normality and pathology, in particular its extent and spatial distribution.

The efficacy of cw Nd:YAG laser trabeculoplasty

The long-term (mean follow up, 51 weeks) efficacy of cw Nd:YAG laser trabeculoplasty in reducing intraocular pressure (IOP) was studied in 106 eyes of 75 patients. Fifty patients (73 eyes) of this group had primary open-angle glaucoma; 11 (17), mixed glaucoma; 10 (12), pseudoexfoliation syndrome; and 4 (4), secondary glaucoma of varied etiology. Fifty laser impacts were delivered over 180 degrees of the circumference of the chamber angle with an Nd:YAG laser working in the cw mode (spot diameter, 100 microns; exposure duration, from 200 to 300 milliseconds; constant power level, 9 W, resulting in 1.8 to 2.7 J/pulse and a total energy dose/session of 90 to 135 J). In a few cases, an exposure duration of 400 milliseconds was used, corresponding to a pulse energy of 3.6 J/pulse and a total energy dose/session of 180 J. Success was defined as a reduction in IOP to 22 mm Hg or less without any further laser or surgical intervention. The cumulative success rate was 97.2% at 1 month, 93.3% at 3 months, 83.3% at 6 months, 78.7% at 12 months, and 71.5% at 24 months. Thus, the efficacy of cw Nd:YAG laser trabeculoplasty is comparable to that reported for trabeculoplasty performed using the argon laser (ALT), the Nd:YAG laser working in the free-running mode, and the diode laser. Biomicroscopy failed to reveal any serious inflammatory reactions persisting longer than 1 week. We conclude that cw Nd:YAG laser trabeculoplasty is a safe and effective alternative to ALT.

Doppler duplex for the evaluation of the degree of stenosis in carotid arteries in the rat

This study evaluates the accuracy of the Doppler duplex technique for providing reliable information about the level of stenosis in microanastomoses. Stenoses ranging between 30 and 85 percent of the cross-sectional area of carotid arteries were evaluated in rats. Peak systolic velocities were measured in prestenotic, stenotic, and poststenotic segments, using the duplex technique. Surgical results with duplex measurements were expressed as percentage of stenosis (calculated from a ratio of two cross-sectional areas), and later correlated. The correlation coefficient between the two sets of measurements was 0.82 (p < 0.01), and the hypothesis of a simple linear relationship was clearly accepted (p = 0.92). Results of the study show that duplex measurements become increasingly unreliable in stenoses with severity less than 50 percent. With increasing degrees of stenosis (50 percent and above), the variance of measurements with duplex decreases. According to the data, the limiting value for the duplex method appears to lie at about 85 percent. When methods for continuous measurement of flap perfusion indicate a hindrance of inflow, Doppler duplex can provide valuable information about the causes. This technique can be used clinically for the evaluation of microanastomoses in 1-mm vessels. In clinical cases, if a 50 percent or more stenosis is diagnosed by duplex technique, the measurement should be repeated within 1 to 2 hr. If the stenosis persists or intensifies, revision should be considered.

Evaluation of numerical displays of visual field data by human observers--the definition of scotomas and clusters by human interpreters

Numerical printouts of 23 visual field examinations performed with glaucoma program G1 were analyzed by 3 perimetrists. The task consisted of defining the existence of clusters or scotomas. Considerable discrepancy with regard to the existence or the size of clusters and/or scotomas was found among the three perimetrists. The median difference in number of clusters as compared for each pair of interpreters was found to differ from zero at a significance level of 5% (Wilcoxon's signed-rank nonparametric test). These findings suggest that the interpretation of a visual field status by human observers will always remain subjective and to a large extent contradictory. This situation calls for the implementation of interpretative computer software to supplement the currently available algorithms.

A functionally based approach to the treatment of self-injurious behavior

This study examined the efficacy of basing treatment interventions for self-injurious behavior on data gathered in functional assessment sessions designed to evaluate the environmental determinants that control the rate of responding. Two moderate and one severely retarded school-age children served as subjects in this study. Data from the assessments revealed that Subjects 1 and 2 emitted the highest rates of self-injury under positive reinforcement conditions, while Subject 3 exhibited higher rates during sensory-input alone conditions. Treatments, implemented by classroom teachers, consisted of differential reinforcement procedures that sought to replace the self-injury with functionally equivalent responses. Results of the interventions indicate that self-injury that is maintained by socially mediated reinforcers could be reduced through the training of alternative communicative responses. In addition, self-injury that functioned as sensory stimulation was reduced by the application of a mild restraint and differential reinforcement of incompatible response procedure. These results are discussed in relation to the identified motivational determinants of the responses and the limitations of such assessments.