Pilot study on the use of basophil activation tests and skin tests for the prevention of allergic transfusion reactions

Background and objectives

Management of severe allergic transfusion reactions (ATR) is challenging. In this study, we investigate the usefulness of skin tests and basophil activation tests (BAT) in chronically transfused patients for the prevention of future ATR.

Materials and methods

BAT and skin tests were carried with the supernatant of red blood cell (RBC) units for a sickle-cell disease patient under chronic exchange transfusion who has presented a severe ATR, in order to prevent potential future ATR. If the results for both BAT and skin tests were negative, the RBC units could be transfused to the patient. If either one of the results was positive, the tested RBC unit was discarded for the patient.

Results

192 RBC units were tested with both tests. The level of results concordance between the two tests was 95%. Out of the 169 negative units with both tests, 118 units were transfused to the patient for which he presented no ATR.

Conclusion

In our study, combining both BAT and skin tests was associated with a good negative predictive value since we were able to safely transfuse our patient. Further studies are still necessary to confirm this result but this pilot study indicates that skin tests and BAT might help prevent ATR. When BAT is not available, skin tests may also be useful in preventing ATR.

Chronic spontaneous urticaria: Evidence of systemic microcirculatory changes

BACKGROUND

Chronic spontaneous urticaria (CSU) is a chronic inflammatory skin disease where activation of endothelial cells (ECs) at sites of skin lesions leads to increased blood flow, leakage of fluid into the skin, cellular infiltration, and vascular remodeling. To understand the disease duration and the sometimes vague systemic symptoms accompanying flares, the objective of this study was to examine if CSU comes with systemic vascular changes at the microcirculatory level.

METHODS

We investigated CSU patients (n = 49) and healthy controls (HCs, n = 44) for microcirculatory differences by nailfold videocapillaroscopy (NVC) and for blood levels of the soluble EC biomarkers serum vascular endothelial growth factor (VEGF), soluble E-selectin, and stem cell factor (SCF). Patients were also assessed for clinical characteristics, disease activity, and markers of autoimmune CSU (aiCSU).

RESULTS

CSU patients had significantly lower capillary density, more capillary malformations, and more irregular capillary dilations than HCs on NVC. Serum levels of VEGF, soluble E selectin and SCF were similar in CSU patients and HCs. CSU patients with higher VEGF levels had significantly more abnormal capillaries. Patients with markers of aiCSU, that is, low IgE levels or increased anti-TPO levels, had significantly more capillaries and less capillary dilations than those without.

CONCLUSION

Our results suggest that CSU comes with systemic microcirculatory changes, which may be driven, in part, by VEGF.

Chronic Spontaneous Urticaria in Belgium: Deciphering the Clinical Profile and Treatment of Patients Visiting an Urban City Immunology Department

BACKGROUND

Chronic urticaria (CSU) is a chronic inflammatory mast cell-driven disorder of which reliable clinical data in Belgium are lacking. This study focusses on clinical characteristics of CSU patients presenting at an urban Immunology-Allergology department.

METHODS

Outpatients with CSU were included from 2018 to 2021. Clinical characteristics, Dermatology Life Quality Index (DLQI) and Urticaria activity score (UAS7) were collected by thorough anamnesis and questionnaires. Furthermore, patients underwent provocational testing, an autologous serum skin test (ASST) and a blood analysis.

RESULTS

The study included 49 CSU patients and 20 non-CSU subjects. CSU was distributed differently with age and sex, showing higher numbers in female patients below the age of 46 years. 67% of CSU patients had accompanying angioedema of which 9% were reported genital. CSU patients scored a mean 8/30 on their DLQI questionnaire. There was no significant difference in immunoglobulin E (IgE), C-reactive protein, and tryptase levels between CSU patients and controls. Oral glucocorticosteroids were prescribed in 23% of CSU patients during their disease course though only half of these patients had a severity grade 4 CSU. In 82% of the included CSU patients, Urticaria Control Test (UCT) scores were below 12. When we hypothetically considered low IgE levels and high IgG anti-thyroid peroxidase levels as differentiation marker for autoimmune (ai)CSU and non-aiCSU, we found that 4% of all included CSU patients could be considered aiCSU.

CONCLUSION

Generally, the inner-city population displayed the same clinical characteristics, as previous cohorts from Northern Europe. The relatively high rate of CSU patients receiving oral glucocorticosteroid treatment for their disease though not always classified as severe, underlines the need to train doctors of various specialties in the treatment algorithms of CSU. Furthermore, by looking at potential autoimmune characteristics, our findings open perspectives on the identification of new routinely used clinical parameters for the detection of aiCSU, a relatively small immunological subtype of CSU.

Sex-biased expression of selected chromosome x-linked microRNAs with potent regulatory effect on the inflammatory response in children with cystic fibrosis: A preliminary pilot investigation

Previous studies have reported sex disparity in cystic fibrosis (CF) disease, with females experiencing more pulmonary exacerbations and frequent microbial infections resulting in shorter survival expectancy. This concerns both pubertal and prepubertal females, which is in support to the prominent role of gene dosage rather than the hormonal status. The underlying mechanisms are still poorly understood. The X chromosome codes for a large number of micro-RNAs (miRNAs) that play a crucial role in the post-transcriptional regulation of several genes involved in various biological processes, including inflammation. However, their level of expression in CF males and females has not been sufficiently explored. In this study, we compared in male and female CF patients the expression of selected X-linked miRNAs involved in inflammatory processes. Cytokine and chemokine profiles were also evaluated at both protein and transcript levels and cross-analyzed with the miRNA expression levels. We observed increased expression of miR-223-3p, miR-106a-5p, miR-221-3p and miR-502-5p in CF patients compared to healthy controls. Interestingly, the overexpression of miR-221-3p was found to be significantly higher in CF girls than in CF boys and this correlates positively with IL-1β. Moreover, we found a trend toward lower expression in CF girls than in CF boys of suppressor of cytokine signaling 1 (SOCS1) and the ubiquitin-editing enzyme PDLIM2, two mRNA targets of miR-221-3p that are known to inhibit the NF-κB pathway. Collectively, this clinical study highlights a sex-bias in X-linked miR-221-3p expression in blood cells and its potential contribution to sustaining a higher inflammatory response in CF girls.

Novel role of UHRF1 in the epigenetic repression of the latent HIV-1

BACKGROUND

The multiplicity, heterogeneity, and dynamic nature of human immunodeficiency virus type-1 (HIV-1) latency mechanisms are reflected in the current lack of functional cure for HIV-1. Accordingly, all classes of latency-reversing agents (LRAs) have been reported to present variable ex vivo potencies. Here, we investigated the molecular mechanisms underlying the potency variability of one LRA: the DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-AzadC).

METHODS

We employed epigenetic interrogation methods (electrophoretic mobility shift assays, chromatin immunoprecipitation, Infinium array) in complementary HIV-1 infection models (latently-infected T-cell line models, primary CD4+ T-cell models and ex vivo cultures of PBMCs from HIV+ individuals). Extracellular staining of cell surface receptors and intracellular metabolic activity were measured in drug-treated cells. HIV-1 expression in reactivation studies was explored by combining the measures of capsid p24Gag protein, green fluorescence protein signal, intracellular and extracellular viral RNA and viral DNA.

FINDINGS

We uncovered specific demethylation CpG signatures induced by 5-AzadC in the HIV-1 promoter. By analyzing the binding modalities to these CpG, we revealed the recruitment of the epigenetic integrator Ubiquitin-like with PHD and RING finger domain 1 (UHRF1) to the HIV-1 promoter. We showed that UHRF1 redundantly binds to the HIV-1 promoter with different binding modalities where DNA methylation was either non-essential, essential or enhancing UHRF1 binding. We further demonstrated the role of UHRF1 in the epigenetic repression of the latent viral promoter by a concerted control of DNA and histone methylations.

INTERPRETATION

A better understanding of the molecular mechanisms of HIV-1 latency allows for the development of innovative antiviral strategies. As a proof-of-concept, we showed that pharmacological inhibition of UHRF1 in ex vivo HIV+ patient cell cultures resulted in potent viral reactivation from latency. Together, we identify UHRF1 as a novel actor in HIV-1 epigenetic silencing and highlight that it constitutes a new molecular target for HIV-1 cure strategies.

FUNDING

Funding was provided by the Belgian National Fund for Scientific Research (F.R.S.-FNRS, Belgium), the « Fondation Roi Baudouin », the NEAT (European AIDS Treatment Network) program, the Internationale Brachet Stiftung, ViiV Healthcare, the Télévie, the Walloon Region (« Fonds de Maturation »), « Les Amis des Instituts Pasteur à Bruxelles, asbl », the University of Brussels (Action de Recherche Concertée ULB grant), the Marie Skodowska Curie COFUND action, the European Union's Horizon 2020 research and innovation program under grant agreement No 691119-EU4HIVCURE-H2020-MSCA-RISE-2015, the French Agency for Research on AIDS and Viral Hepatitis (ANRS), the Sidaction and the "Alsace contre le Cancer" Foundation. This work is supported by 1UM1AI164562-01, co-funded by National Heart, Lung and Blood Institute, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Neurological Disorders and Stroke, National Institute on Drug Abuse and the National Institute of Allergy and Infectious Diseases.

Tocilizumab-Induced Unexpected Increase of Several Inflammatory Cytokines in Critically Ill COVID-19 Patients: The Anti-Inflammatory Side of IL-6

Early evidence during the coronavirus disease 2019 (COVID-19) pandemic indicated high levels of interleukin (IL)-6 in patients with severe COVID-19. This led to the off-label use of tocilizumab (TCZ) during the first wave of the pandemic. While the monoclonal antibody blocks IL-6 pathway, its effect on other inflammatory cytokines remains poorly described. To better understand the effect of TCZ on the biological inflammatory profile, we monitored a large panel of inflammatory cytokines in critically ill COVID-19 patients receiving off-label TCZ. Twenty-three patients with polymerase chain reaction-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection were included in the study, among which 15 patients received TCZ and 8 patients did not. Serum samples were collected for 8 days, before and following TCZ administration or hospital admission for the control group. Serum profile of 12 cytokines (IL-1β, -2, -4, -6, -8, -10, -12, -13, -17, -18, tumor necrosis factor α (TNF-α), interferon-gamma (IFN-γ), and sIL-6R were assessed in these two groups. Although the increased IL-6 concentrations after TCZ infusion were expected, we observed an unexpected increase in IL-1β, -2, -4, -10, -12p70, -18, and sIL-6R levels in the treated patients with maximal values reaching 2 to 4 days after TCZ. In contrast, no change in cytokine levels was observed in the control group. Our results suggested that some inflammatory pathways escape IL-6R blockade and even appeared amplified. This finding highlights an old observation of the anti-inflammatory effects of IL-6 as already suggested over 20 years ago. Clinical Trial Registration number: NCT04346017.

Helminth infection induces non-functional sensitization to house dust mites

BACKGROUND

IgE characterizes the humoral response of allergic sensitization but less is known about what modulates its function and why some patients present clinical symptoms for a given IgE level and others do not. An IgE response also occurs during helminth diseases, independently of allergic symptoms. This response could be a model of non-functional IgE.

OBJECTIVE

To study the IgE response against environmental allergens induced during natural helminth infection.

METHODS

In 28 non allergic subjects from the periphery of Ho Chi Minh city with (H+, n = 18) and without helminth infection (H-, n = 10), we measured IgE and IgG4 against several components of Dermatophagoïdes pteronyssinus (Dpt) and Ascaris (a marker of immunization against nematodes), and determined the IgE component sensitization profile using microarray ISAC biochips. The functional ability of IgE to induce degranulation of cultured mast cells was evaluated in the presence of Dpt.

RESULTS

Non allergic H+ subjects exhibited higher levels of IgE against Dpt compared to H- subjects. Dpt IgE were not functional in vitro and did not recognize usual Dpt major allergens. IgE recognized other component allergens that belong to different protein families, and most were glycosylated. Depletion of IgE recognizing carbohydrate cross-reactive determinant (CCD) did not induce a reduction in Dpt IgE. The Dpt IgG4 were not significantly different.

CONCLUSION

Helminth infections induced IgE against allergens such as Dpt and molecular components that belong to different sources as well as against CCD (such as β-1,2-xylose and/or ⍺-1,3-fucose substituted N-glycans). Dpt IgE were not able to induce degranulation of mast cells and were not explained by sensitization to usual major allergens or N-glycans.

Hookworm treatment induces a decrease of suppressive regulatory T cell associated with a Th2 inflammatory response

Background

Like other helminths, hookworms (HW) induce a regulatory immune response able to modulate and dampen reactivity of the host to antigens. No data about the evolution of the immune response after treatment are available. We aim to phenotype the regulatory immune response during natural HW infection and its evolution after treatment.

Methodology

Twenty hookworm infected (HW+) and 14 non-infected subjects HW–from endemic area in the periphery of Ho Chi Minh City were included. Blood and feces samples were obtained before, 2 and 4 weeks after treatment with Albendazole 400mg. Additional samples were obtained at 3 and 12 months in the HW+ group. Hematological parameters, Treg (CD4+CD25^hiFoxP3^hi) and surface molecules (CD39, CD62L, ICOS, PD-1, CD45RA) were measured as well as inflammatory and lymphocytes differentiation cytokines such as IL-1β, IL-6, IFNγ, IL-4, IL-17, IL-10, IL-2 and TGFβ.

Results

HW+ subjects showed higher Treg, TregICOS+, Treg PD1-, TregCD62L+ and CD45RA+FoxP3^lo resting Treg (rTreg). CD45RA-FoxP3^lo non-suppressive Treg cells were also increased. No preferential Th1/Th2 orientation was observed, nor difference for IL-10 between two groups. After treatment, Treg, TregICOS+, TregCD62L+, Treg PD1- and rTreg decreased while IL-4 and IL-6 cytokines increased.

Conclusion

During HW infection, Treg are increased and characterized by a heterogeneous population: a highly suppressive as well as a non-suppressive T cells phenotype. After treatment, Treg with immune-suppressive phenotype exhibited a decrease parallel to an inflammatory Th2 response.

Discrimination of COVID-19 From Inflammation-Induced Cytokine Storm Syndromes Using Disease-Related Blood Biomarkers

Objective

Infection with the novel coronavirus SARS–CoV‐2 triggers severe illness with high mortality in a subgroup of patients. Such a critical course of COVID‐19 is thought to be associated with the development of cytokine storm, a condition seen in macrophage activation syndrome (MAS) and secondary hemophagocytic lymphohistiocytosis (HLH). However, specific data demonstrating a clear association of cytokine storm with severe COVID‐19 are still lacking. The aim of this study was to directly address whether immune activation in COVID‐19 does indeed mimic the conditions found in these classic cytokine storm syndromes.

Methods

Levels of 22 biomarkers were quantified in serum samples from patients with COVID‐19 (n = 30 patients, n = 83 longitudinal samples in total), patients with secondary HLH/MAS (n = 50), and healthy controls (n = 9). Measurements were performed using bead array assays and single‐marker enzyme‐linked immunosorbent assay. Serum biomarker levels were assessed for correlations with disease outcome.

Results

In patients with secondary HLH/MAS, we observed pronounced activation of the interleukin‐18 (IL‐18)–interferon‐γ axis, increased serum levels of IL‐1 receptor antagonist, intercellular adhesion molecule 1, and IL‐8, and strongly reduced levels of soluble Fas ligand in the course of SARS–CoV‐2 infection. These observations appeared to discriminate immune dysregulation in critical COVID‐19 from the well‐recognized characteristics of other cytokine storm syndromes.

Conclusion

Serum biomarker profiles clearly separate COVID‐19 from MAS or secondary HLH in terms of distinguishing the severe systemic hyperinflammation that occurs following SARS–CoV‐2 infection. These findings could be useful in determining the efficacy of drugs targeting key molecules and pathways specifically associated with systemic cytokine storm conditions in the treatment of COVID‐19.

Tetanus seroprotection in people living with HIV: Risk factors for seronegativity, evaluation of medical history and a rapid dipstick test

OBJECTIVES

Tetanus is a vaccine-preventable disease. Booster immunization is required in order to induce long-lived tetanus-toxoid (TT) specific antibody response. We investigated the prevalence and risk factors of TT seronegativity in a cohort of people living with HIV (PWH) in Belgium along with the respective performance of vaccine history and a rapid dipstick test (Tetanus Quick Stick ® or TQS) compared to ELISA testing.

METHODS

PWH were prospectively enrolled and answered a questionnaire. ELISA was performed on serum or plasma using a commercial kit. A TT antibody level ≥ 0.15 IU / mL was considered protective. The TQS test was performed on a limited number of subjects.

RESULTS

Three-hundred forty-four subjects were included. The prevalence of tetanus seroprotection was 84,9%. Median age was 46.7 and 68% were born outside Belgium. Antiretroviral therapy coverage was almost universal (98.5%). After multivariable analysis, two risk factors were independently associated with TT seronegativity: an education level equivalent or below than secondary school and being born outside Europe. Vaccine history was shown to be unreliable (sensitivity: 43.8%; specificity: 76.5%; positive predictive value: 91.4% and negative predictive value :19.3%). The correlation between vaccine history and tetanus seroprotection was low (kappa coefficient = 0.09). The TQS performances were good (sensitivity 86.4%, specificity 96.0%, positive predictive value 99.3%, negative predictive value 52.17%). The correlation between TQS and tetanus seroprotection was substantial (kappa coefficient = 0.61).

CONCLUSIONS

In this cohort of PWH with a high proportion of migrants, socio-demographic and educational factors were associated with TT seronegativity while HIV-related factors were not, indicating that vaccine information should be tailored to cultural and educational background. As vaccine history is not reliable, TQS could represent an efficient tool for screening of TT-seronegativity.

Covid-19 and blood groups: ABO antibody levels may also matter

BACKGROUND

Susceptibility to Covid-19 has been found to be associated with the ABO blood group, with O type individuals being at a lower risk. However, the underlying mechanism has not been elucidated. Here, we aimed to test the hypothesis that Covid-19 patients might have lower levels of ABO antibodies than non-infected individuals as they could offer some degree of protection.

METHODS

After showing that the viral spike protein harbors the ABO glycan epitopes when produced by cells expressing the relevant glycosyltransferases, like upper respiratory tract epithelial cells, we enrolled 290 patients with Covid-19 and 276 asymptomatic controls to compare their levels of natural ABO blood group antibodies.

RESULTS

We found significantly lower IgM anti-A + anti-B agglutination scores in blood group O patients (76.93 vs 88.29, P-value = 0.034) and lower levels of anti-B (24.93 vs 30.40, P-value = 0.028) and anti-A antibodies (28.56 vs 36.50, P-value = 0.048) in blood group A and blood group B patients, respectively, compared to controls.

CONCLUSION

In this study, we showed that ABO antibody levels are significantly lower in Covid-19 patients compared to controls. These findings could indicate that patients with low levels of ABO antibodies are at higher risk of being infected.

Biomarkers for Early Diagnosis of Hemophagocytic Lymphohistiocytosis in Critically Ill Patients

Many biomarkers have been proposed for the diagnosis of secondary hemophagocytic lymphohistiocytosis (HLH) in adults, but comparative studies are lacking. We analyzed ferritin, glycosylated ferritin, soluble CD25, CD163 and CD14, IL-6, IFN-γ, IL-18, IL-10, IL-1ß, IL-12p70, IL-17α, IP-10, and CXCL9 levels to differentiate HLH from sepsis in critically ill patients. Of 120 patients, HLH was confirmed for 14 patients. Among the biomarkers tested, ferritin, IL-18, and glycosylated ferritin were the most efficient parameters for early diagnosis of HLH. With a sensitivity set at 85%, ferritin, IL-18, and glycosylated ferritin were the biomarkers with the highest specificity: 84, 79, and 71% respectively. Combining IL-18 with the HScore provided a new score with an increased specificity compared to the HScore alone, 86% compared to 70% with a sensitivity set at 100%. A distinct cytokine pattern was highlighted in patients with malignancy-triggered HLH, with highly increased levels of INF-ɣ and CXCL9, compared to HLH secondary to infection. This is the largest study available to date, comparing diagnostic biomarkers for HLH on a cohort of critically ill adult patients. Serum ferritin was the most discriminating parameter for early diagnosis of secondary HLH. IL18^*HScore was identified as a highly potential score.

Interleukine-6 in critically ill COVID-19 patients: A retrospective analysis

INTRODUCTION

Coronavirus disease 2019 (COVID-19) appeared in China in December 2019 and has spread around the world. High Interleukin-6 (IL-6) levels in COVID-19 patients suggest that a cytokine storm may play a major role in the pathophysiology and are considered as a relevant parameter in predicting most severe course of disease. The aim of this study was to assess repeated IL-6 levels in critically ill COVID-19 patients admitted to our Intensive Care Unit (ICU) and to evaluate their relationship with patient's severity and outcome.

METHODS

We conducted a retrospective study on patients admitted to the ICU with a diagnosis of COVID-19 between March 10 (i.e. the date of the first admitted patients) and April 30, 2020. Demographic, clinical and laboratory data were collected at admission. On the day of IL-6 blood concentration measurement, we also collected results of D-Dimers, C-Reactive Protein, white blood cells and lymphocytes count, lactate dehydrogenase (LDH) and ferritin as well as microbiological samples, whenever present.

RESULTS

Of a total of 65 patients with COVID-19 admitted to our ICU we included 41 patients with repeated measure of IL-6. There was a significant difference in IL-6 levels between survivors and non-survivors over time (p = 0.001); moreover, non survivors had a significantly higher IL-6 maximal value when compared to survivors (720 [349-2116] vs. 336 [195-646] pg/mL, p = 0.01). The IL-6 maximal value had a significant predictive value of ICU mortality (AUROC 0.73 [95% CI 0.57-0.89]; p = 0.01).

CONCLUSIONS

Repeated measurements of IL-6 can help clinicians in identifying critically ill COVID-19 patients with the highest risk of poor prognosis.

A score combining early detection of cytokines accurately predicts COVID-19 severity and intensive care unit transfer

OBJECTIVES

We aimed to explore cytokine profile in patients as it relates to Coronavirus Disease 2019 (COVID-19) severity, and to establish a predictive cytokine score to discriminate severe from non-severe cases and provide a prognosis parameter for patients that will require intensive care unit (ICU) transfer.

METHODS

Serum samples of 63 patients diagnosed with SARS-CoV-2 infection were collected early after hospital admission (day 0-3). Patients were categorized in five groups based on the clinical presentation, the PaO2/FiO2 ratio and the requirement of mechanical ventilation.

RESULTS

Three cytokines, IL-6, IL-8 and IL-10, were markedly higher in severe forms (n = 44) than in non-severe forms (n = 19) (p < 0.005). A score combining levels of these three cytokines (IL-6*IL-8*IL-10) had the highest performance to predict severity: sensitivity of 86.4% (95% CI, 72.4-94.8) and specificity of 94.7% (95% CI, 74.0-99.9) for a cutoff value of 2068 pg/mL. Elevated levels of IL-6, IL-8 and IL-10 were also found in critically ill patients. The combination of IL-6*IL-10 serum levels allowed the highest predictability for ICU transfer: AUC of 0.898 (p < 0.0001).

CONCLUSION

The combinatorial IL-6*IL-8*IL-10 score at presentation was highly predictive of the progression to a severe form of the disease, and could contribute to improve patient triage and to adapt therapeutic strategy within clinical trials more accurately and efficiently.

The protective effect of rural life on mite sensitization disappears among urban migrants in the South of Vietnam

Background

Rapid urbanization combined with rural migration to urban areas in southern Vietnam could be risk factors for allergen sensitization, contributing to chronic respiratory diseases (CRD). We aimed to evaluate the prevalence of mite sensitization and its relation to house dust characteristics among rural and urban native and migrating populations with CRD.

Methods

Rural (n = 19) and urban (n = 46) dwellings were defined on the basis of a home typology. Controls were western Belgian houses (n = 14). Besides the house characteristics, both endotoxin and mite allergens were measured in the settled dusts. The sensitization to mite allergens was defined by positive skin prick test (SPT) and concentration of specific IgE (sIgE)≥ 0.7 U/mL. The prevalence of mite sensitization was evaluated among 610 patients with CRD and compared according to both their home types and places of birth and residences.

Results

The concentration of endotoxin (but not mite allergen) was higher in rural compared to urban dusts (440 (95%CI: 314–566) versus 170 (95%CI: 115–226) EU/mg; p < 0.0001). The prevalence of positive sIgE to Der p1 and Der p2 was significantly lower in rural (9% and 5%) compared to urban (15% and 9%) population, consistent with the positive SPT to mite (14% and 21%, respectively). Among the urban migrants, the risk of mite sensitization (SPT) was higher compared to the rural natives (OR: 1.79 (1.02–3.15), p < 0.05) and not different to the urban ones (OR: 1.35 (0.82–2.23) p NS).

Conclusion

In Vietnam, associated with higher endotoxin (but not allergen) dust concentrations, the risk of mite sensitization was lower in rural compared to the native urban population, but this protective effect could disappear among rural to urban migrants.

Alteration of humoral, cellular and cytokine immune response to inactivated influenza vaccine in patients with Sickle Cell Disease

Introduction

Patients suffering from Sickle Cell Disease (SCD) are at increased risk for complications due to influenza virus. Annual influenza vaccination is strongly recommended but few clinical studies have assessed its immunogenicity in individuals with SCD. The aim of this study was to explore the biological efficacy of annual influenza vaccination in SCD patients by characterizing both their humoral and cell-mediated immunity against influenza antigen. We also aimed to investigate these immunological responses among SCD individuals according to their treatment (hydroxyurea (HU), chronic blood transfusions (CT), both HU and CT or none of them).

Methods

Seventy-two SCD patients (49 receiving HU, 9 on CT, 7 with both and 7 without treatment) and 30 healthy controls were included in the study. All subjects received the tetravalent influenza α-RIX-Tetra® vaccine from the 2016–2017 or 2017–2018 season.

Results

Protective anti-influenza HAI titers were obtained for the majority of SCD patients one month after vaccination but seroconversion rates in patient groups were strongly decreased compared to controls. Immune cell counts, particularly cellular memory including memory T and memory B cells, were greatly reduced in SCD individuals. Functional activation assays confirmed a poorer CD8⁺ T cell memory. We also document an imbalance of cytokines after influenza vaccination in SCD individuals with an INFγ/IL-10 ratio (Th1-type/Treg-type response) significantly lower in the SCD cohort.

Conclusion

SCD patients undergoing CT showed altered immune regulation as compared to other treatment subgroups. Altogether, the cytokine imbalance, the high regulatory T cell levels and the low memory lymphocyte subset levels observed in the SCD cohort, namely for those on CT, suggest a poor ability of SCD patients to fight against influenza infection. Nevertheless, our serological data support current clinical practice for annual influenza vaccination, though immunogenicity to other vaccines involving immunological memory might be hampered in SCD patients and should be further investigated.

The Number of X Chromosomes Influences Inflammatory Cytokine Production Following Toll-Like Receptor Stimulation

Sex differences are observed in the evolution of numerous inflammatory conditions. Women exhibit better clinical courses compared to men in acute inflammatory processes, yet worse prognosis in several chronic inflammatory diseases. Inflammatory markers are significantly different between prepubertal boys and girls, whose sex steroid levels are very low, suggesting genetics play a role. To evaluate the potential influence of the X chromosome, we studied cytokine production and protein phosphorylation following Toll-like receptor (TLR) activation in whole blood and purified neutrophils and monocytes of healthy adults of both sexes as well as subjects with Klinefelter syndrome. We recorded higher levels of inflammatory cytokines in men compared to both women and patients with Klinefelter syndrome following whole blood stimulation. In purified monocytes, production of inflammatory cytokines was also higher in men compared to women, while Klinefelter subjects expressed the same pattern of cytokine production as males, in contrast with whole blood analyses. These differences remained after adjusting for sex steroid levels. Our study revealed higher cytokine inflammatory responses in men than women, yet also compared to subjects with Klinefelter syndrome, who carry two copies of the X chromosome, like women, and thus potentially benefit from the cellular mosaicism of X-linked genes.

Immunologic mechanisms of a short-course of Lolium perenne peptide immunotherapy: A randomized, double-blind, placebo-controlled trial

BACKGROUND

A 3-week short-course of adjuvant-free hydrolysates of Lolium perenne peptide (LPP) immunotherapy for rhinoconjunctivitis with or without asthma over 4 physician visits is safe, well tolerated, and effective.

OBJECTIVE

We sought to investigate immunologic mechanisms of LPP immunotherapy in a subset of patients who participated in a phase III, multicenter, randomized, double-blind, placebo-controlled trial (clinical.govNCT02560948).

METHODS

Participants were randomized to receive LPP (n = 21) or placebo (n = 11) for 3 weeks over 4 visits. Grass pollen-induced basophil, T-cell, and B-cell responses were evaluated before treatment (visit [V] 2), at the end of treatment (V6), and after the pollen season (V8).

RESULTS

Combined symptom and rescue medication scores (CSMS) were lower during the peak pollen season (-35.1%, P = .03) and throughout the pollen season (-53.7%, P = .03) in the LPP-treated group compared with those in the placebo-treated group. Proportions of CD63⁺ and CD203c^brightCRTH2⁺ basophils were decreased following LPP treatment at V6 (10 ng/mL, P < .0001) and V8 (10 ng/mL, P < .001) compared to V2. No change in the placebo-treated group was observed. Blunting of seasonal increases in levels of grass pollen-specific IgE was observed in LPP-treated but not placebo-treated group. LPP immunotherapy, but not placebo, was associated with a reduction in proportions of IL-4⁺ T_H2 (V6, P = .02), IL-4⁺ (V6, P = .003; V8, P = .004), and IL-21⁺ (V6, P = .003; V8, P = .002) follicular helper T cells. Induction of FoxP3⁺, follicular regulatory T, and IL-10⁺ regulatory B cells were observed at V6 (all P < .05) and V8 (all P < .05) in LPP-treated group. Induction of regulatory B cells was associated with allergen-neutralizing IgG₄-blocking antibodies.

CONCLUSION

For the first time, we demonstrate that the immunologic mechanisms of LPP immunotherapy are underscored by immune modulation in the T- and B-cell compartments, which is necessary for its effect.

What Do We Know About Fish Allergy at the End of the Decade?

Fish allergy is one of the most common food allergies. It is usually considered to be IgE-mediated and correlates well with diagnostic tests such as prick tests and/or determination of specific IgE. Avoidance is the recommended treatment and is generally extended to all fish species. However, new clinical presentations have been described. These include non-IgE-mediated disease, monosensitization, and new syndromes that are sometimes associated, surprisingly, with cross-reactivity. Advances in molecular allergy have provided insights into new allergens and have increased our understanding of cross-reactivity. This paper focuses on recent publications providing information for clinicians involved in the management of fish allergy.

Evaluation of skin prick test to screen dust mite sensitization in chronic respiratory diseases in Southern Vietnam

Background

In the view of the epidemic growth of sensitization to indoor allergens in Southern Vietnam, there is a requirement to screen large population.

Objective

To evaluate skin prick tests (SPTs) as predictors of positive specific IgE (sIgE) to dust allergens, among patients with chronic respiratory diseases (CRDs).

Methods

The sensitization to Blomia tropicalis (Blo t), Dermatophagoides pteronissinus (Der p), and Blattella germanica allergens (Bla g) were evaluated among 610 CRD, both SPT (≥4 mm) and sIgE by immuno-CAP (≥0.7 kU_A/L).

Results

Based on sIgE, 45%, 32%, and 33% of patients with CRD were sensitized to Blo t, Der p, and Bla g, respectively, compared to 19%, 18%, and 13% by SPT. The association between SPT and sIgE was statistically significant, though the Kappa factor was fair (i.e., 0.39 to 0.23). While the specificity of SPT to detect sensitization (compared to sIgE) was >90% among the whole population, the sensitivity was only 34%, 41%, and 24% for Bo t, Der p, and Bla g, suggesting that SPT was not enough sensitive to screen the indoor allergen sensitization. Though, among the <10 pack-year (PY) smokers, the sensitivity was 43% for Blo t, 52% for Der p, and 61% for Blo t and/or Der p, compared to 27%, 30%, and 35% among the ≥10 PY smokers. The sensitivity/specificity was not associated with the diagnosis of asthma compared to chronic obstructive pulmonary disease.

Conclusion

In the present circumstance, SPT to dust mites allergens can be used to detect a sensitization among CRD population in Southern Vietnam.

Limited cross reactivity among arginine kinase allergens from mealworm and cricket edible insects

Insects are seen as a solution to the increasing demand for protein sources for food. However, entomophagy has unfortunately been linked to allergic reactions in Europe with people with professional contacts. As mealworms (Tenebrio molitor) and crickets (Acheta domesticus) have recently become commercially available (both whole or in food formulation) in several European countries, this research assessed the cross allergenicity of arginine kinase (AK). Based on the collection of sera from a entomology laboratory staff, oven cooked insects but also purified AK fractions were tested. Immunoblotting against the protein extracts revealed different Immunoglobulin E reactivity of sera according to the insect target species: two bands (40 and 14 kDa) for crickets and a pattern including light responses at 17, 25 and 37 kDa for mealworms. Focusing on AK, low specific allergenicity was here illustrated and discussed in relation to the development of a safe edible insect consumption by humans.

Diagnosis of Subtype 2B von Willebrand Disease in a Patient with 2A Phenotype of Plasma von Willebrand Factor

Type 2A of von Willebrand disease refers to qualitative variants with decreased platelet dependent function that is associated with the absence of high molecular weight forms of von Willebrand factor (vWF) multimers. Type 2B refers to qualitative variants with increased affinity for platelet glycoprotein lb. In this report we describe the study of a patient who has been previously diagnosed as having subtype 2A von Willebrand disease (vWD), because she had no heightened ristocetin-induced platelet aggregation, no large and intermediate molecular weight von Willebrand factor (vWF) multimers in plasma, and no increase in plasma vWF capacity to bind to normal platelets in the presence of low ristocetin concentrations. The DNA sequencing of the 3’ part of the exon 28 of the vWF gene where most of the subtype 2A mutations have already been identified, did not detect any nucleotide change. At variance, a G to A transition changing the encoded amino acid residue from Val 553 to Met in mature vWF, was found in the 5’ part of this exon. This mutation which has already been found in several unrelated families with 2B vWD and the increased binding of the patient platelet vWF on normal platelets in the presence of low ristocetin concentrations provide evidence for subtype 2B vWD. This study thus illustrates the importance of the molecular characterization of patients in the correct diagnosis and classification of type 2 vWD.

Relationship between mold exposure, specific IgE sensitization, and clinical asthma: A case-control study

BACKGROUND

Most of the findings related to the noxious effect of mold sensitization on asthma come from investigations based on Alternaria alternata, Cladosporium herbarum, and Aspergillus fumigatus. However, species such as Penicillium spp, Cladosporium sphaerospermum, Cladosporium cladosporioides, or Aspergillus versicolor display a more pronounced indoor tropism, and their potential harmful respiratory effects cannot be neglected.

OBJECTIVE

The goal of this work was to relate mold sensitizations with asthma severity and with the level of indoor mold contamination among mold-sensitized patients with asthma and nonsensitized patients with asthma.

METHODS

A case-control study was conducted and several asthma severity markers were compared between patients with asthma with and without mold sensitization. Indoor contamination of patients' dwellings was also investigated.

RESULTS

Our findings confirmed the association between sensitization to A fumigatus and severity for patients with asthma in contrast with sensitization to other species. Indoor mold contamination was detected in approximately 90% of dwellings. Overall mold exposure was not associated with asthma severity. However, regardless of the sensitization, exposure to A fumigatus and Penicillium spp in dust was linked to an increased risk of severe asthma.

CONCLUSION

The harmful nature of mold sensitization and mold exposure for patients with asthma was not confirmed in this study. However, sensitization to A fumigatus was associated with an increased risk for severe asthma. A better investigation of the properties of Penicillium spp is recommended because its exposure was found to be associated with a more pronounced impairment of lung function.

Lolium perenne peptide immunotherapy is well tolerated and elicits a protective B-cell response in seasonal allergic rhinitis patients

BACKGROUND

Systemic allergic reactions are a risk for allergen immunotherapy that utilizes intact allergen preparations. We evaluated the safety, efficacy and immune mechanisms of short-course treatment with adjuvant-free Lolium perenne peptides (LPP) following a 6-week dose-escalation protocol.

METHODS

In a prospective, dose-escalation study, 61 grass pollen-allergic patients received 2 subcutaneous injections of LPP once weekly for 6 weeks. Safety was assessed evaluating local reactions, systemic reactions and adverse events. The clinical effect of LPP was determined by reactivity to the conjunctival provocation test (CPT). Specific IgE, IgG4 and blocking antibodies were measured at baseline (V1), during (V6) and after treatment (V8).

RESULTS

No fatality, serious adverse event or epinephrine use was reported. Mean wheal diameters after injections were <0.6 cm and mean redness diameters <2.5 cm, independent of dose. Transient and mostly mild adverse events were reported in 33 patients. Two patients experienced a grade I and 4 patients a grade II reaction (AWMF classification). At V8, 69.8% of patients became nonreactive to CPT. sIgG4 levels were higher at V6 (8.1-fold, P < .001) and V8 (12.2-fold, P < .001) than at V1. The sIgE:sIgG4 ratio decreased at V6 (-54.6%, P < .001) and V8 (-71.6%, P < .001) compared to V1. The absolute decrease in IgE-facilitated allergen binding was 18% (P < .001) at V6 and 25% (P < .001) at V8.

CONCLUSION

Increasing doses of subcutaneous LPP appeared safe, substantially diminished reactivity to CPT and induced blocking antibodies as early as 4 weeks after treatment initiation. The benefit/risk balance of LPP immunotherapy remains to be further evaluated in large studies.

The Acid-Base Balance and Gender in Inflammation: A Mini-Review

In humans, acid–base balance is crucial to cell homeostasis. Acidosis is observed in numerous inflammatory processes, primarily acute conditions such as sepsis, trauma, or acute respiratory distress where females tend to exhibit better prognosis compared with males. The mechanisms underlying these gender-dependent differences are multiple, probably involving hormonal and genetic factors, particularly the X chromosome. Although pH influences multiple immunological functions, gender differences in acid–base balance have been poorly investigated. In this review, we provide an update on gender differences in human susceptibility to inflammatory diseases. We additionally discuss the potential impact of acid–base balance on the gender bias of the inflammatory response in view of our recent observation that girls present higher neutrophilic inflammation and lower pH with a trend toward better prognosis in severe sepsis. We also highlight the potent role played by endothelial cells in gender differences of inflammation through activation of proton-sensing G protein-coupled receptors.

Differential Susceptibility to Infectious Respiratory Diseases between Males and Females Linked to Sex-Specific Innate Immune Inflammatory Response

It is widely acknowledged that males and females exhibit contrasting degrees of susceptibility to infectious and non-infectious inflammatory diseases. This is particularly observed in respiratory diseases where human males are more likely to be affected by infection-induced acute inflammations compared to females. The type and magnitude of the innate immune inflammatory response play a cardinal role in this sex bias. Animal models mimicking human respiratory diseases have been used to address the biological factors that could explain the distinct outcomes. In this review, we focus on our current knowledge about experimental studies investigating sex-specific differences in infection-induced respiratory diseases and we provide an update on the most important innate immune mechanisms that could explain sex bias of the inflammatory response. We also discuss whether conclusions drawn from animal studies could be relevant to human.

Sequential treatment with 5-aza-2'-deoxycytidine and deacetylase inhibitors reactivates HIV-1

Reactivation of HIV gene expression in latently infected cells together with an efficient cART has been proposed as an adjuvant therapy aimed at eliminating/decreasing the reservoir size. Results from HIV clinical trials using deacetylase inhibitors (HDACIs) question the efficiency of these latency‐reversing agents (LRAs) used alone and underline the need to evaluate other LRAs in combination with HDACIs. Here, we evaluated the therapeutic potential of a demethylating agent (5‐AzadC) in combination with clinically tolerable HDACIs in reactivating HIV‐1 from latency first in vitro and next ex vivo. We showed that a sequential treatment with 5‐AzadC and HDACIs was more effective than the corresponding simultaneous treatment both in vitro and ex vivo. Interestingly, only two of the sequential LRA combinatory treatments tested induced HIV‐1 particle recovery in a higher manner than the drugs alone ex vivo and at concentrations lower than the human tolerable plasmatic concentrations. Taken together, our data reveal the benefit of using combinations of 5‐AzadC with an HDACI and, for the first time, the importance of treatment time schedule for LRA combinations in order to reactivate HIV.

Inflammation induced by inhaled lipopolysaccharide depends on particle size in healthy volunteers

AIMS

In drug development, the anti-inflammatory properties of new molecules in the lung are currently tested using the inhaled lipopolysaccharide (LPS) model. The total and regional lung bioavailability of inhaled particles depends significantly on their size. The objective of the present study was to compare inflammatory responses in healthy volunteers after the inhalation of LPS of varying droplet size.

METHODS

Three nebulizers were characterized by different droplet size distributions [mean mass median aerodynamic diameters: Microcirrus (2.0 μm), MB2 (3.2 μm) and Pari (7.9 μm)]. Participants inhaled three boluses of a 20 μg (technetium 99 m-labelled) solution of LPS, randomly delivered by each nebulizer. We measured the lung deposition of the nebulized LPS by gamma-scintigraphy, while blood and sputum biomarkers were evaluated before and after challenges.

RESULTS

MB2 and Pari achieved greater lung deposition than Microcirrus [171.5 (±72.9) and 217.6 (±97.8) counts pixel^-1 , respectively, vs. 67.9 (±20.6) counts pixel^-1 ; P < 0.01]. MB2 and Pari caused higher levels of blood C-reactive protein and more total cells and neutrophils in sputum compared with Microcirrus (P < 0.05). C-reactive protein levels correlated positively with lung deposition (P < 0.01).

CONCLUSIONS

Inhalation of large droplets of LPS gave rise to greater lung deposition and induced a more pronounced systemic and bronchial inflammatory response than small droplets. The systemic inflammatory response correlated with lung deposition. NCT01081392.

Performances of the H-Score for Diagnosis of Hemophagocytic Lymphohistiocytosis in Adult and Pediatric Patients

OBJECTIVES

In this study, we compared the performances of adapted hemophagocytic lymphohistiocytosis (HLH)-2004 guidelines with those of the new diagnostic H-score to identify patients with HLH in a multicenter cohort consisting of adult and pediatric cases of suspected HLH.

METHODS

The study sample consisted of 147 cases, including 20 adults and 16 children with HLH. Two sets of biological data were evaluated: at presentation and the maximal values reached during the episode.

RESULTS

At presentation, for both children and adults, the H-score was more efficient than adapted HLH-2004 guidelines to identify HLH. The diagnostic sensitivity and specificity were respectively 100% and 80% for children and 90% and 79% for adults. However, for adults, performances became comparable between adapted HLH-2004 guidelines and H-score as patient clinical status worsened. The specificity decreased to 73% for the same sensitivity.

CONCLUSIONS

The adapted HLH-2004 guidelines seem less powerful and H-score seems to be more appropriate for children, which may be due to less significantly marked biological features. For adults, H-score performances are better when determined at presentation. The cutoff value of the H-score should be adapted depending on the target population to obtain optimal specificity.

Anti-GQ1b antibody syndrome presenting as acute isolated bilateral ophthalmoplegia: Report on two patients and review of the literature

BACKGROUND

Miller Fisher syndrome (MFS) is an acute polyradiculoneuritis regarded as an uncommon clinical variant of Guillain-Barré syndrome (GBS). MFS is characterized by the acute onset of the clinical triad of ophthalmoplegia, cereballar ataxia and areflexia. Atypical forms of MFS presenting as isolated ophthalmoplegia without ataxia have been rarely described, mostly in adults.

PATIENTS

We present two cases of acute isolated bilateral ophthalmoplegia in childhood, both occurring shortly after Campylobacter jejuni enteritis. Serum analysis of anti-ganglioside antibodies revealed elevated levels of anti-GQ1b IgG and IgM. We observed in both children complete spontaneous resolution several weeks after onset.

CONCLUSION

The cases of the two patients confirm the rare but possible occurrence of atypical MFS in young children a few weeks after gastrointestinal infection. Identification of high levels of anti-GQ1b antibodies in the serum may help confirm the diagnosis of MFS even when its clinical presentation is incomplete.

Automated point-of-care testing for ABO agglutination test: proof of concept and validation

BACKGROUND AND OBJECTIVES

ABO-incompatible red blood cell transfusions still represent an important hazard in transfusion medicine. Therefore, some countries have introduced a systematic bedside ABO agglutination test checking that the right blood is given to the right patient. However, this strategy requires an extremely time-consuming learning programme and relies on a subjective interpretation of ABO test cards agglutination. We developed a prototype of a fully automated device performing the bedside agglutination test that could be completed by reading of a barcoded wristband. This POCT checks the ABO compatibility between the patient and the blood bag.

MATERIALS AND METHODS

Proof of concept and analytical validation of the prototype has been completed on 451 blood samples: 238 donor packed red blood cells, 137 consecutive unselected patients for whom a blood group determination had been ordered and on 76 patient samples selected with pathology that could possibly interfere with or impair performances of the assay.

RESULTS

We observed 100% concordance for ABO blood groups between the POCT and the laboratory instrument.

CONCLUSION

These preliminary results demonstrate the feasibility of ABO determination with a simple POCT device eliminating manipulation and subjective interpretation responsible for transfusion errors. This device should be linked to the blood bank system allowing all cross-check of the results.

Anti-TNF inhibits the airways neutrophilic inflammation induced by inhaled endotoxin in human

BACKGROUND

Inhaled endotoxin induces airways'neutrophilia, in human. TNF-a being a key cytokine in the response to endotoxin, the effect of anti-TNF on the endotoxin-induced neutrophilic response was evaluated among healthy volunteers.

METHODS

Among a population of 30 healthy subjects, an induced-sputum was collected 2 weeks before, and 24 hours after an inhalation of 20 mcg endotoxin (E. coli 026:B6). Then, the subjects were randomized into 3 parallel groups treated with control, oral methylprednisolone 20 mg/day during 7 days or anti-TNF (adalimumab, Humira®, Abbott) 40 mg s.c.. One week later, an induced-sputum was sampled, 24 hours after an inhalation of endotoxin.

RESULTS

After endotoxin inhalation, the number of total cells, neutrophils and macrophages was significantly increased (p <0.001). Compared to the response to endotoxin among the control group, anti-TNF inhibited the endotoxin-induced neutrophil influx, both in relative (51.3 (±6.4)% versus 26.2 (±5.3)%, p <0.002) and in absolute values (1321 (443-3935) cells/mcL versus 247 (68-906) cells/mcL, p <0.02). The endotoxin-induced neutrophilic response was not significantly modified among the control group and oral corticosteroid group.

CONCLUSIONS

While oral corticosteroid had no effect, anti-TNF inhibited the neutrophil influx in sputum, induced by inhalation of endotoxin, in human subject. The endotoxin model could be an early predictor of clinical efficacy of novel therapeutics.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02252809 (EudraCT2008-005526-37).

Eculizumab in anti-factor h antibodies associated with atypical hemolytic uremic syndrome

Atypical hemolytic uremic syndrome (aHUS) is a life-threatening multisystemic condition often leading to end-stage renal failure. It results from an increased activation of the alternative pathway of the complement system due to mutations of genes coding for inhibitors of this pathway or from autoantibodies directed against them. Eculizumab is a monoclonal antibody directed against complement component C5 and inhibiting the activation of the effector limb of the complement system. Its efficacy has already been demonstrated in aHUS. The present article reports for the first time the use of eculizumab in a patient presenting with aHUS associated with circulating anti-complement Factor H autoantibodies and complicated by cardiac and neurologic symptoms. Our observation highlights the efficacy of eculizumab in this form of aHUS not only on renal symptoms but also on the extrarenal symptoms. It also suggests that eculizumab should be used very promptly after aHUS presentation to prevent life-threatening complications and to reduce the risk of chronic disabilities. To obtain a complete inhibition of the effector limb activation, the advised dosage must be respected. After this initial therapy in the autoimmune aHUS form, a long-term immunosuppressive treatment should be considered, to prevent relapses by reducing anti-complement Factor H autoantibody plasma levels.

Dimensions of pure chronic fatigue: psychophysical, cognitive and biological correlates in the chronic fatigue syndrome

OBJECTIVES

To investigate associated dimensions of fatigue regarding cognitive impairment, psychomotor performances, muscular effort power and circulating cytokine levels and their relations to symptom intensity in a sample of pure chronic fatigue syndrome (CFS) patients without overlapping objective sleepiness or sleep disorders.

METHODS

16 CFS patients were compared to 14 matched controls. We assessed structured symptom-scales, polysomnography, multiple sleep latency tests, attention (Zazzo-Cancellation ZCT, digit-symbol-substitution DSST), psychomotor vigilance and speed (PVT, finger tapping test, FTT), dynamometer handgrip force (tonic and phasic trials) and circulating cytokines (IFN-γ, IL-1b, IL-6, IL-8, IL-10, TNF-α).

RESULTS

In addition to fatigue, CFS patients presented with higher affective symptom intensity and worse perceived sleep quality. Polysomnography showed more slow-wave sleep and microarousals in CFS but similar sleep time, efficiency and light-sleep durations than controls. Patients presented with impaired attention (DSST, ZCT), slower reaction times (PVT) but not with lower hit rates (FTT). Notwithstanding lower grip strength during tonic and phasic trials, CFS also presented with higher fatigability during phasic trials. Cytokine levels were increased for IL-1b, IL-8, IL-10 and TNF-α and fatigue intensity was correlated to grip strength and IL-8.

CONCLUSIONS

In contrast to sleepiness, chronic fatigue is a more complex phenomenon that cannot be reduced to one single measured dimension (i.e., sleep propensity). Showing its relations to different measurements, our study reflects this multidimensionality, in a psychosomatic disorder such as CFS. To obtain objective information, routine assessments of fatigue should rule out sleepiness, combine aspects of mental and physical fatigue and focus on fatigability.

The "normobaric oxygen paradox": a new tool for the anesthetist?

Hypoxia is the natural trigger for endogenous EPO production but recently the use of intermittent hyperoxia to stimulate EPO has been postulated and this phenomenon has been called the "normobaric oxygen paradox" (NOP). The "NOP" is a mechanism by which oxygen regulates the expression of the Hypoxia Inducible Factor 1 alpha (HIF-1α). The HIF-1α-depending gene regulation is responsible for many different genetic expressions including EPO and VEGF. It has been proposed that relative changes of oxygen availability rather than steady state hypoxic or hyperoxic conditions, play an important role in HIF transcriptional effects. According to this hypothesis, the cell interprets the return to normoxia after a hyperoxic event as an oxygen shortage, and induces HIF-1-regulated gene synthesis, including EPO. Being both a hormone and a cytokine, the actual actions of EPO are complex; its clinical utility has been postulated for neuroprotection and cardioprotection. The precise level of inspired oxygen and the exact timeframe for its iterative administration are not totally known. N-Acetyl-L-Cysteine (NAC) supplementation has been shown to help. All the reported data demonstrate how hyperoxic and hypoxic states can potentially be manipulated if oxygen is been considered as a multifaceted molecule more than just a gas.

Transfusion support of autoimmune hemolytic anemia: how could the blood group genotyping help?

Conventional pretransfusion testing based on hemagglutination assays can be challenging for patients with autoimmune hemolytic anemia (AIHA) because of the presence of auto-antibodies. It has been suggested that deoxyribonucleic acid-based methods could be more efficient in the selection of antigen-matched red blood cell units in those settings. Because of the high risk of alloimmunization of these patients and the labor-intensive nature of adsorption techniques, we decided to evaluate the feasibility of selecting antigen-matched units on the basis of RBC genotyping. We included in our routine RBC genotyping program samples from 7 patients with AIHA presenting a strongly positive direct antiglobulin test. This made the routine compatibility tests difficult. Most patients had previously received transfusions because of warm AIHA. Matched donor units were selected according to the genotype. For all but 1 patient, blood group genotyping could be done on time to allow antigen-matched transfusion. Four patients received antigen-matched red blood cell units based on RBC genotyping and for 1 patient the fact that no matched units were available led us to postpone the transfusion. After each transfusion, the recovery was recorded and considered satisfactory for all transfused patients.

Expression of calgranulin A/B heterodimer after acute inhalation of endotoxin: proteomic approach and validation

Background

The acute inhalation of endotoxin mimicks several aspects of the inflammation related to chronic obstructive pulmonary disease (COPD). The aim of the current study was to identify and to validate biomarkers of endotoxin-induced airways’ inflammation.

Methods

The cellular count in the induced-sputum, was measured before and after an inhalation of 20 mcg endotoxin, in 8 healthy volunteers. A proteomic analysis was applied to identify the more relevant proteins expression, before measurement by ELISA. The amplitude and the repeatability of the markers were evaluated among another population of 12 healthy subjects.

Results

There was a significant rise of viable cells (p <0.01), macrophages (p <0.05), and neutrophils (p <0.02) 24 hours after endotoxin inhalation, and of neutrophils (p <0.02) and lymphocytes (p <0.05) at 6 hours. Among the highest amplitude responses, the two dimensional electrophoretic separation shown proteolytic activity and overexpression of protein spots. By MALDI-TOF mass spectrometry, the last were identified as calgranulin A and B. The expression of the bioactive A/B heterodimeric complex was confirmed by ELISA both in the sputum (p <0.01) and at the blood level (p <0.01). The intra-subject repeatability of the sputum calgranulin A/B was highly significant (p <0.0001).

Conclusion

In healthy subjects, the inhalation of endotoxin induced expression of sputum calgranulin A/B that could be a biomarker of the endotoxin response/exposure.