Tailored anticoagulant treatment after a first venous thromboembolism: protocol of the Leiden Thrombosis Recurrence Risk Prevention (L-TRRiP) study - cohort-based randomised controlled trial.

INTRODUCTION: Patients with a first venous thromboembolism (VTE) are at risk of recurrence. Recurrent VTE (rVTE) can be prevented by extended anticoagulant therapy, but this comes at the cost of an increased risk of bleeding. It is still uncertain whether patients with an intermediate recurrence risk or with a high recurrence and high bleeding risk will benefit from extended anticoagulant treatment, and whether a strategy where anticoagulant duration is tailored on the predicted risks of rVTE and bleeding can improve outcomes. The aim of the Leiden Thrombosis Recurrence Risk Prevention (L-TRRiP) study is to evaluate the outcomes of tailored duration of long-term anticoagulant treatment based on individualised assessment of rVTE and major bleeding risks. METHODS AND ANALYSIS: The L-TRRiP study is a multicentre, open-label, cohort-based, randomised controlled trial, including patients with a first VTE. We classify the risk of rVTE and major bleeding using the L-TRRiP and VTE-BLEED scores, respectively. After 3 months of anticoagulant therapy, patients with a low rVTE risk will discontinue anticoagulant treatment, patients with a high rVTE and low bleeding risk will continue anticoagulant treatment, whereas all other patients will be randomised to continue or discontinue anticoagulant treatment. All patients will be followed up for at least 2 years. Inclusion will continue until the randomised group consists of 608 patients; we estimate to include 1600 patients in total. The primary outcome is the combined incidence of rVTE and major bleeding in the randomised group after 2 years of follow-up. Secondary outcomes include the incidence of rVTE and major bleeding, functional outcomes, quality of life and cost-effectiveness in all patients. ETHICS AND DISSEMINATION: The protocol was approved by the Medical Research Ethics Committee Leiden-Den Haag-Delft. Results are expected in 2028 and will be disseminated through peer-reviewed journals and during (inter)national conferences. TRIAL REGISTRATION NUMBER: NCT06087952.

A scoping review protocol on diagnostic strategies to detect occult malignancies in individuals with ischemic stroke.

BACKGROUND: Emerging data show an increased risk of ischemic stroke in patients with a new diagnosis of cancer. As the risk of stroke begins to increase 150 days before cancer is diagnosed, stroke may be the first clinical manifestation of undiagnosed cancer. About 6% of patients with cryptogenic ischemic stroke (unknown etiology after diagnostic evaluations) are diagnosed with cancer within one year. However, the optimal cancer screening strategy in this population is not known. We aim to conduct a scoping review of screening strategies for occult cancer in individuals with ischemic stroke. METHODS: Electronic databases including MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCOhost) and Scopus will be systematically searched to identify articles that report on screening strategies for occult cancer in individuals with ischemic stroke. At least two investigators will independently perform two-stage study selection consisting of title/abstract screening and full-text review, followed by data extraction. Thereafter, a thematic analysis will be conducted to provide an overview of what diagnostic tests/strategies have been used, and their clinical utility in terms of positive and negative predictive value (when available). CONCLUSION: We anticipate that the findings of this scoping review will identify strategies used to detect occult cancer in individuals with ischemic stroke and summarize their clinical utility (if reported). Addressing this knowledge gap will help guide the development of future clinical trials on occult cancer screening patients with ischemic stroke.

All-cause mortality after major gastrointestinal bleeding among patients receiving direct oral anticoagulants: a protocol for a systematic review and meta-analysis.

BACKGROUND: Gastrointestinal (GI) bleeding represents the single most frequent site of anticoagulant-related bleeding. Adverse outcomes after major GI bleeding including mortality are not well characterized and, as a result, may be underappreciated in clinical practice. We aim to conduct a systematic review and meta-analysis of the risk for 30-day all-cause mortality after major GI bleeding among patients receiving DOACs. METHODS: Electronic databases including MEDLINE, EMBASE, and Cochrane CENTRAL will be systematically searched to identify randomized controlled trials and prospective and retrospective cohort studies reporting 30-day all-cause mortality in adults with DOAC-related major GI bleeding. At least two investigators will independently perform study selection, risk of bias assessment, and data extraction. The proportion of deaths following a major GI event relative to the number of major GI bleeding events will be calculated for each individual study, and results across studies will be pooled using random-effects meta-analysis. We will assess risk of bias using criteria proposed by the GRADE group for prognostic studies. DISCUSSION: The findings of this systematic review and meta-analysis will provide clinicians and patients with estimates of mortality after the most common major bleeding event to support shared decision making about anticoagulation management. TRIAL REGISTRATION: PROSPERO CRD42022295815.

Practical recommendations to combine small-molecule inhibitors and direct oral anticoagulants in patients with nonsmall cell lung cancer.

BACKGROUND: The risk for thromboembolisms in nonsmall cell lung cancer (NSCLC) patients is increased and often requires treatment or prophylaxis with direct oral anticoagulants (DOACs). Small-molecule inhibitors (SMIs) to treat NSCLC may cause relevant drug-drug interactions (DDIs) with DOACs. Guidance on how to combine these drugs is lacking, leaving patients at risk of clotting or bleeding. Here, we give practical recommendations to manage these DDIs. METHODS: For all DOACs and SMIs approved in Europe and the USA up to December 2021, a literature review was executed and reviews by the US Food and Drug Administration and European Medicines Agency were analysed for information on DDIs. A DDI potency classification for DOACs was composed and brought together with DDI characteristics of each SMI, resulting in recommendations for each combination. RESULTS: Half of the combinations result in relevant DDIs, requiring an intervention to prevent ineffective or toxic treatment with DOACs. These actions include dose adjustments, separation of administration or switching between anticoagulant therapies. Combinations of SMIs with edoxaban never cause relevant DDIs, compared to more than half of combinations with other DOACs and even increasing to almost all combinations with rivaroxaban. CONCLUSIONS: Combinations of SMIs and DOACs often result in relevant DDIs that can be prevented by adjusting the DOAC dosage, separation of administration or switching between anticoagulants.

Effects of dalteparin on anti-Xa activities cannot be predicted in critically ill COVID-19 patients.

Critically ill COVID-19 patients are at high risk of thromboembolic events despite routine-dosed low-molecular-weight heparin thromboprophylaxis. However, in recent randomized trials increased-intensity thromboprophylaxis seemed futile and possibly even harmful. In this explorative pharmacokinetic (PK) study we measured anti-Xa activities on frequent timepoints in 15 critically ill COVID-19 patients receiving dalteparin and performed PK analysis by nonlinear mixed-effect modelling. A linear one-compartment model with first-order kinetics provided a good fit. However, wide interindividual variation in dalteparin absorption (variance 78%) and clearance (variance 34%) was observed, unexplained by routine clinical covariates. Using the final PK model for Monte Carlo simulations, we predicted increased-intensity dalteparin to result in anti-Xa activities well over prophylactic targets (0.2-0.4 IU/mL) in the majority of patients. Therapeutic-intensity dalteparin results in supratherapeutic anti-Xa levels (target 0.6-1.0 IU/mL) in 19% of patients and subtherapeutic levels in 22%. Therefore, anti-Xa measurements should guide high-intensity dalteparin in critically ill COVID-19 patients.

Prior use of therapeutic anticoagulation does not protect against COVID-19 related clinical outcomes in hospitalized patients: A propensity score-matched cohort study.

The hypercoagulable state observed in COVID-19 could be responsible for morbidity and mortality. In this retrospective study we investigated whether therapeutic anticoagulation prior to infection has a beneficial effect in hospitalized COVID-19 patients. This study included 1154 COVID-19 patients admitted to 6 hospitals in the Netherlands between March and May 2020. We applied 1:3 propensity score matching to evaluate the association between prior therapeutic anticoagulation use and clinical outcome, with in hospital mortality as primary endpoint. In total, 190 (16%) patients used therapeutic anticoagulation prior to admission. In the propensity score matched analyses, we observed no associations between prior use of therapeutic anticoagulation and overall mortality (risk ratio 1.02 [95% confidence interval; 0.80-1.30]) or length of hospital stay (7.0 [4-12] vs. 7.0 [4-12] days, P = .69), although we observed a lower risk of pulmonary embolism (0.19 [0.05-0.80]). This study shows that prior use of therapeutic anticoagulation is not associated with improved clinical outcome in hospitalized COVID-19 patients.

COVID-19-associated coagulopathy and antithrombotic agents-lessons after 1 year.

COVID-19 is associated with a high incidence of thrombotic complications, which can be explained by the complex and unique interplay between coronaviruses and endothelial cells, the local and systemic inflammatory response, and the coagulation system. Empirically, an intensified dose of thrombosis prophylaxis is being used in patients admitted to hospital with COVID-19 and several guidelines on this topic have been published, although the insufficiency of high quality and direct evidence has led to weak recommendations. In this Viewpoint we summarise the pathophysiology of COVID-19 coagulopathy in the context of patients who are ambulant, admitted to hospital, and critically ill or non-critically ill, and those post-discharge from hospital. We also review data from randomised controlled trials in the past year of antithrombotic therapy in patients who are critically ill. These data provide the first high-quality evidence on optimal use of antithrombotic therapy in patients with COVID-19. Pharmacological thromboprophylaxis is not routinely recommended for patients who are ambulant and post-discharge. A first ever trial in non-critically ill patients who were admitted to hospital has shown that a therapeutic dose of low-molecular-weight heparin might improve clinical outcomes in this population. In critically ill patients, this same treatment does not improve outcomes and prophylactic dose anticoagulant thromboprophylaxis is recommended. In the upcoming months we expect numerous data from the ongoing antithrombotic COVID-19 studies to guide clinicians at different stages of the disease.

Multicentric experience with interferon gamma therapy in sepsis induced immunosuppression. A case series.

BACKGROUND: The sepsis-induced immunodepression contributes to impaired clinical outcomes of various stress conditions. This syndrome is well documented and characterized by attenuated function of innate and adaptive immune cells. Several pharmacological interventions aimed to restore the immune response are emerging of which interferon-gamma (IFNγ) is one. It is of paramount relevance to obtain clinical information on optimal timing of the IFNγ-treatment, -tolerance, -effectiveness and outcome before performing a RCT. We describe the effects of IFNγ in a cohort of 18 adult and 2 pediatric sepsis patients. METHODS: In this open-label prospective multi-center case-series, IFNγ treatment was initiated in patients selected on clinical and immunological criteria early (< 4 days) or late (> 7 days) following the onset of sepsis. The data collected in 18 adults and 2 liver transplanted pediatric patients were: clinical scores, monocyte expression of HLA-DR (flow cytometry), lymphocyte immune-phenotyping (flow cytometry), IL-6 and IL-10 plasma levels (ELISA), bacterial cultures, disease severity, and mortality. RESULTS: In 15 out of 18 patients IFNγ treatment was associated with an increase of median HLA-DR expression from 2666 [IQ 1547; 4991] to 12,451 [IQ 4166; 19,707], while the absolute number of lymphocyte subpopulations were not affected, except for the decrease number of NK cells 94.5 [23; 136] to 32.5 [13; 90.8] (0.0625)]. Plasma levels of IL-6 464 [201-770] to 108 (89-140) ng/mL (p = 0.04) and IL-10 from IL-10 from 29 [12-59] to 9 [1-15] pg/mL decreased significantly. Three patients who received IFNγ early after ICU admission (<4 days) died. The other patients had a rapid clinical improvement assessed by the SOFA score and bacterial cultures that were repeatedly positive became negative. The 2 pediatric cases improved rapidly, but 1 died for hemorrhagic complication. CONCLUSION: Guided by clinical and immunological monitoring, adjunctive immunotherapy with IFNγ appears well-tolerated in our cases and improves immune host defense in sepsis induced immuno suppression. Randomized clinical studies to assess its potential clinical benefit are warranted.

[Checkpoint inhibitor induced diabetes mellitus]. / Checkpointremmer geïnduceerde diabetes mellitus.

BACKGROUND Checkpoint inhibitors are relatively new anti-cancer medicines that activate tumour cell immunity. CASE DESCRIPTION We describe two patients who presented to the emergency department due to severe ketoacidosis, this being the first symptom of diabetes in said patients. A few weeks prior to this, they each commenced treatment with the checkpoint inhibitor pembrolizumab. HbA1c level, assessed in one of the patients, was not elevated upon presentation. CONCLUSION Type 1 diabetes mellitus is a rare, but potentially life-threatening, complication of treatment with checkpoint inhibitors. However, routine measurement of glucose or HbA1c levels is not useful in patients who are treated with checkpoint inhibitors. Both patients and healthcare professionals should be (made) aware of the symptoms of hyperglycaemia, thereby ensuring immediate treatment with insulin in order to prevent severe ketoacidosis.

Trained Innate Immunity as a Novel Mechanism Linking Infection and the Development of Atherosclerosis.

RATIONALE: There is strong epidemiological evidence for an association between acute and chronic infections and the occurrence of atherosclerotic cardiovascular disease. The underlying pathophysiological mechanisms remain unclear. Monocyte-derived macrophages are the most abundant immune cells in atherosclerotic plaques. It has recently been established that monocytes/macrophages can develop a long-lasting proinflammatory phenotype after brief stimulation with micro-organisms or microbial products, which has been termed trained immunity. OBJECTIVE: The aim of this study is to assess whether trained immunity mediates the link between infections and atherosclerotic cardiovascular disease. METHODS AND RESULTS: Brief exposure of monocytes to various micro-organisms results in the development of macrophages with a persistent proinflammatory phenotype: this represents a de facto nonspecific innate immune memory, which has been termed trained immunity. This is mediated by epigenetic reprogramming at the level of histone methylation and a profound rewiring of intracellular metabolism. Although this mechanism offers powerful protection against reinfection, trained macrophages display an atherogenic phenotype in terms of cytokine production and foam cell formation. Trained monocytes are present up to 3 months after experimental infection in humans. Moreover, a trained immunity phenotype is present in patients with established atherosclerosis. CONCLUSIONS: We propose that trained immunity provides the missing mechanistic link that explains the association between infections and atherosclerosis. Therefore, pharmacological modulation of trained immunity has the potential to prevent infection-related atherosclerotic cardiovascular disease in the future.

Initial anticoagulation in patients with pulmonary embolism: thrombolysis, unfractionated heparin, LMWH, fondaparinux, or DOACs?

The initial treatment of haemodynamically stable patients with pulmonary embolism (PE) has dramatically changed since the introduction of low molecular weight heparins (LMWHs). With the recent discovery of the direct oral anticoagulant drugs (DOACs), initial treatment of PE will be simplified even further. In several large clinical trials it has been demonstrated that DOACs are not inferior to standard therapy for the initial treatment of PE, and because of their practicability they are becoming the agents of first choice. However, many relative contraindications to DOACs were exclusion criteria in the clinical trials. Therefore, LMWHs will continue to play an important role in initial PE treatment and in some cases there still is a role for unfractionated heparin (UFH). In this review we will give an overview of the biophysical, pharmacokinetic and pharmacodynamic properties of anticoagulants currently available for the initial management of PE. In addition, we will provide a comprehensive overview of the indications for the use of UFH, LMWHs and DOACs in the initial management of PE from a pharmacokinetic/-dynamic point of view.

Adjuvant interferon-gamma immunotherapy in a patient with progressive cerebral Nocardia abscesses.

Despite advances in medical care, mortality due to cerebral Nocardia abscesses remains unacceptably high. The case of a typical immunocompromised patient, who deteriorated clinically despite optimal antimicrobial treatment, is reported here. Adjuvant immunotherapy with interferon-gamma resulted in partial restoration of the immune response and a corresponding clinical and radiographic recovery.

Leukocyte phosphodiesterase expression after lipopolysaccharide and during sepsis and its relationship with HLA-DR expression.

Phosphodiesterases (PDEs) may modulate inflammatory pathways, but PDE expression is poorly documented in humans with sepsis. Using quantitative PCR on whole blood leukocytes, we characterized PDE mRNA expression in healthy volunteers (n = 20), healthy volunteers given lipopolysaccharide (LPS; n = 18), and critically ill patients with (n = 20) and without (n = 20) sepsis. PDE4B protein expression was also studied in magnetic-activated cell sorting (MACS)-isolated CD15+ neutrophils (from 7 healthy volunteers, 5 patients without and 5 with sepsis). We studied relationships between PDE expression, HLA-DR (mRNA and expression on CD14+ monocytes), tumor necrosis factor (TNF)-α, and interleukin (IL)-10 levels. LPS administration in volunteers was associated with increases in PDE4B and PDE4D and decreases in PDE4A and PDE7A mRNAs. The observed global down-regulation of the HLA-DR complex was correlated with PDE7A. Critically ill patients had lower TNF-α/IL-10 mRNA ratios than the volunteers had and global down-regulation of the HLA-DR complex. Septic patients had persistently lower mRNA levels of PDE7A, PDE4A, and 4B (also at a protein level) and decreasing levels of PDE4D over time. Low PDE4D mRNA levels correlated negatively with HLA-DMA and HLA-DMB. LPS administration and sepsis are, therefore, associated with different PDE mRNA expression patterns. The effect of PDE changes on immune dysfunction and HLA-DR expression requires further investigation.

Broad defects in the energy metabolism of leukocytes underlie immunoparalysis in sepsis.

The acute phase of sepsis is characterized by a strong inflammatory reaction. At later stages in some patients, immunoparalysis may be encountered, which is associated with a poor outcome. By transcriptional and metabolic profiling of human patients with sepsis, we found that a shift from oxidative phosphorylation to aerobic glycolysis was an important component of initial activation of host defense. Blocking metabolic pathways with metformin diminished cytokine production and increased mortality in systemic fungal infection in mice. In contrast, in leukocytes rendered tolerant by exposure to lipopolysaccharide or after isolation from patients with sepsis and immunoparalysis, a generalized metabolic defect at the level of both glycolysis and oxidative metabolism was apparent, which was restored after recovery of the patients. Finally, the immunometabolic defects in humans were partially restored by therapy with recombinant interferon-γ, which suggested that metabolic processes might represent a therapeutic target in sepsis.

Interferon-gamma Immunotherapy in a Patient With Refractory Disseminated Candidiasis.

Despite advances in supportive care and novel antifungal agents, mortality caused by invasive Candida infection is high. A 3-year-old boy with disseminated Candida dubliniensis infection during induction chemotherapy for acute lymphoblastic leukemia deteriorated despite resolution of neutropenia and appropriate antifungal treatment. Monocyte human leukocyte antigen-DR expression was extremely low, suggesting immunoparalysis. Adjuvant immunotherapy with interferon-gamma restored the immune response, which was accompanied by clinical and radiographic recovery.

EFFECTS OF EXPERIMENTAL HUMAN ENDOTOXEMIA ON DIAPHRAGM FUNCTION.

INTRODUCTION: Systemic inflammation is a well-known risk factor for respiratory muscle weakness. Studies using animal models of inflammation have shown that endotoxin administration induces diaphragm dysfunction. However, the effects of in vivo endotoxin administration on diaphragm function in humans have not been studied. Our aim was to evaluate diaphragm function in a model of systemic inflammation in healthy subjects. METHODS: Two groups of 12 male volunteers received an intravenous bolus of 2 ng/kg of Escherichia coli lipopolysaccharide (LPS) and were monitored until 8 h after LPS administration. In the first group, the twitch transdiaphragmatic pressure (Pditw) and compound muscle action potential of the diaphragm (CMAPdi) were measured. In addition, plasma levels of cytokines, heart rate, and arterial blood pressure were measured. In the second group, catecholamines as well as respiratory rate and blood gas values were measured. Diaphragm ultrasonography was performed in four subjects with severe shivering. RESULTS: Lipopolysaccharide administration resulted in flulike symptoms, hemodynamic alterations, and increased plasma levels of cytokines. The Pditw increased after LPS administration from 31.2 ±â€Š2.0 cmH2O (baseline) to 38.8 ±â€Š2.0 cmH2O (t = 1 h) and 35.4 ±â€Š2.0 cmH2O (t = 1.5 h). There was no correlation between cytokine plasma levels and the Pditw. We found a trend toward a gradual decrease in the CMAPdi from 0.78 ±â€Š0.07 mV (baseline) to 0.58 ±â€Š0.05 mV (t = 2 h). Respiratory rate increased after LPS administration from 16.8 ±â€Š0.5 breaths/min (baseline) to 20.3 ±â€Š0.6 breaths/min (t = 4 h), with a resulting decrease in PaCO2 of 0.5 ±â€Š0.1 kPa. Plasma levels of epinephrine peaked at t = 1.5 h, with an increase of 1.3 ±â€Š0.3 nmol/L from baseline. Rapid diaphragm contractions consistent with shivering were observed. CONCLUSIONS: This study shows that, in contrast to diaphragm dysfunction observed in animal models of inflammation, in vivo diaphragm contractility is augmented in the early phase after low-dose endotoxin administration in humans.

BCG Vaccination Enhances the Immunogenicity of Subsequent Influenza Vaccination in Healthy Volunteers: A Randomized, Placebo-Controlled Pilot Study.

BACKGROUND: Influenza-related morbidity and mortality remain high. Seasonal vaccination is the backbone of influenza management but does not always result in protective antibody titers. Nonspecific effects of BCG vaccination related to enhanced function of myeloid antigen-presenting cells have been reported. We hypothesized that BCG vaccination could also enhance immune responses to influenza vaccination. METHODS: Healthy volunteers received either live attenuated BCG vaccine (n = 20) or placebo (n = 20) in a randomized fashion, followed by intramuscular injection of trivalent influenza vaccine 14 days later. Hemagglutination-inhibiting (HI) antibodies and cellular immunity measured by ex vivo leukocyte responses were assessed. RESULTS: In BCG-vaccinated subjects, HI antibody responses against the 2009 pandemic influenza A(H1N1) vaccine strain were significantly enhanced, compared with the placebo group, and there was a trend toward more-rapid seroconversion. Additionally, apart from enhanced proinflammatory leukocyte responses following BCG vaccination, nonspecific effects of influenza vaccination were also observed, with modulation of cytokine responses against unrelated pathogens. CONCLUSIONS: BCG vaccination prior to influenza vaccination results in a more pronounced increase and accelerated induction of functional antibody responses against the 2009 pandemic influenza A(H1N1) vaccine strain. These results may have implications for the design of vaccination strategies and could lead to improvement of vaccination efficacy.

Gamma-irradiated bacille Calmette-Guérin vaccination does not modulate the innate immune response during experimental human endotoxemia in adult males.

Bacille Calmette-Guérin (BCG) vaccine exerts nonspecific immunostimulatory effects and may therefore represent a novel therapeutic option to treat sepsis-induced immunoparalysis. We investigated whether BCG vaccination modulates the systemic innate immune response in humans in vivo during experimental endotoxemia. We used inactivated gamma-irradiated BCG vaccine because of the potential risk of disseminated disease with the live vaccine in immunoparalyzed patients. In a randomized double-blind placebo-controlled study, healthy male volunteers were vaccinated with gamma-irradiated BCG (n = 10) or placebo (n = 10) and received 1 ng/kg lipopolysaccharide (LPS) intravenously on day 5 after vaccination to assess the in vivo immune response. Peripheral blood mononuclear cells were stimulated with various related and unrelated pathogens 5, 8 to 10, and 25 to 35 days after vaccination to assess ex vivo immune responses. BCG vaccination resulted in a scar in 90% of vaccinated subjects. LPS administration elicited a profound systemic immune response, characterized by increased levels of pro- and anti-inflammatory cytokines, hemodynamic changes, and flu-like symptoms. However, BCG modulated neither this in vivo immune response, nor ex vivo leukocyte responses at any time point. In conclusion, gamma-irradiated BCG is unlikely to represent an effective treatment option to restore immunocompetence in patients with sepsis-induced immunoparalysis. This trial is registered with NCT02085590.

The effects of orally administered Beta-glucan on innate immune responses in humans, a randomized open-label intervention pilot-study.

RATIONALE: To prevent or combat infection, increasing the effectiveness of the immune response is highly desirable, especially in case of compromised immune system function. However, immunostimulatory therapies are scarce, expensive, and often have unwanted side-effects. ß-glucans have been shown to exert immunostimulatory effects in vitro and in vivo in experimental animal models. Oral ß-glucan is inexpensive and well-tolerated, and therefore may represent a promising immunostimulatory compound for human use. METHODS: We performed a randomized open-label intervention pilot-study in 15 healthy male volunteers. Subjects were randomized to either the ß -glucan (n = 10) or the control group (n = 5). Subjects in the ß-glucan group ingested ß-glucan 1000 mg once daily for 7 days. Blood was sampled at various time-points to determine ß-glucan serum levels, perform ex vivo stimulation of leukocytes, and analyze microbicidal activity. RESULTS: ß-glucan was barely detectable in serum of volunteers at all time-points. Furthermore, neither cytokine production nor microbicidal activity of leukocytes were affected by orally administered ß-glucan. CONCLUSION: The present study does not support the use of oral ß-glucan to enhance innate immune responses in humans. TRIAL REGISTRATION: ClinicalTrials.gov NCT01727895.