CCR3, CCR5, CCR8 and CXCR3 expression in memory T helper cells from allergic rhinitis patients, asymptomatically sensitized and healthy individuals

BACKGROUND: Chemokine receptors have been suggested to be preferentially expressed on CD4+ T cells with CCR3 and CCR8 linked to the T helper (Th) 2 subset and CCR5 and CXCR3 to the Th1 subset, however this remains controversial. OBJECTIVE: Our aim was to compare the CCR3, CCR5, CCR8 and CXCR3 expression in memory Th cells from allergic, asymptomatically sensitized and healthy individuals. METHODS: Peripheral blood mononuclear cells from 8 pollen allergic rhinitis patients, 10 asymptomatically sensitized and 10 healthy individuals were stimulated for 7 days with allergen or tetanus toxoid. CCR3, CCR5, CCR8, CXCR3, CD4 and CD45RO were detected by flow cytometry. RESULTS: No differences in chemokine receptor expression were observed between the three groups on day 0, and seven days of unstimulated culture did not change the expression. Both antigenic stimuli increased the chemokine receptor expression, tetanus toxoid being the most potent. No differences in percentage chemokine receptor positive memory Th cells were observed between the three groups on day 7. Only a change in MFI for CCR5 was significantly different between the three groups after allergen stimulation of the Th cells. CONCLUSION: We conclude that even though allergen and antigen induced increased chemokine receptor expression, no differences in profiles were identified in memory Th cells from patient groups with different atopic status

Quantification of anti-A of IgM or IgG isotype using three different methodologies

Background: Reliability of ABO-antibody measurement is important in the context of supplying low-titer ABO incompatible plasma-containing blood products. This study investigated the correlation of anti-A measurements between three different titer methodologies. Methods: Thirty-four blood group O individuals were included. IgM and IgG anti-A was measured by three different methods: (1) manual method (Bio-Rad ID-gel card), (2) automated method (Immucor NEO), (3) flow cytometry (FC) with calibration in molecules of equivalent fluorochrome (MEF). Data were log2 transformed to titer steps (TS) and log2 MEF, respectively. All three methods were benchmarked against the 14/300 WHO anti-A/anti-B standard reagent. Results: The correlation between the manual and automated methods was statistically significant for both IgM (Spearman's rs = 0.89, p &lt;.0001) and IgG (rs = 0.95, p &lt;.0001). The mean TS difference between the manual and automated methods was 0.61 for IgM (p =.0033) and 2.1 for IgG (p &lt;.0001). The manual method yielded IgM titer results that were generally 1 titer step higher than the automated method, whereas for the IgG titrations the difference was generally a median of 2 TS higher. The FC median log2 MEF level was significantly correlated with TS of IgG and IgM for both manual and automated agglutination-based titer methods (0.69 ≤ r2 ≤ 0.91). With the WHO standard reagent, the manual method produced the expected results while the automated method's results were 1 TS lower for both IgM and IgG at all dilutions tested. Conclusion: These results indicate that all three methods are suitable for measuring anti-A in group O whole blood.</p

Association between neutropenia and IgG antineutrophil antibodies in a case of <i>CD40LG </i>deficiency due to two novel mutations

This case suggests a mechanistic rationale for the clinical efficacy of intravenous immunoglobulins (IVIG) in treating CD40 ligand (CD40L) deficiency associated neutropenia as it is the first reported instance of free and cell-bound antineutrophil antibodies in a case of CD40L deficiency, accompanied by a prolonged and clinically severe neutropenia.</p

Reduced membrane attack complex formation in umbilical cord blood during Eculizumab treatment of the mother:A case report

Background: Atypical hemolytic uremic syndrome (aHUS) is a disorder of the microvasculature with hemolytic anemia, thrombocytopenia and acute kidney injury. Nowadays, aHUS is successfully treated with eculizumab, a humanized, chimeric IgG2/4 kappa antibody, which binds human complement C5 and blocks generation of C5a and membrane-attack-complex. Case presentation: A 25-year-old woman with end stage renal disease due to relapsing atypical hemolytic uremic syndrome had a relapse of the disease during pregnancy. She was treated with eculizumab. We measured reduced formation of the membrane-attack complex in newborn's umbilical cord vein blood using the sensitive and specific Palarasah-Nielsen-ELISA. Conclusions: Eculizumab treatment of the mother with end stage renal disease may cause reduced innate immunity which could render newborns more susceptible to infections.</p

Prolonged viral shedding of SARS-CoV-2 in two immunocompromised patients, a case report

BACKGROUND: The duration of viable Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) shedding in immunocompromised patients is still unknown. This case report describes the duration of viable SARS-CoV-2 in two immunocompromised patients with completely different clinical courses and further addresses the immunological aspects.CASE PRESENTATIONS: Oropharyngeal swaps were collected continuously during hospitalization for two immunocompromised patients infected with SARS-CoV-2 and sent for analysis to real time reverse transcription polymerase chain reaction (RT-PCR), viral culture assessed by plaque assay and full genome sequencing. Blood samples for flow cytometry and further immunological analysis were taken once during admission. One patient was without symptoms of Coronavirus disease 2019 (COVID-19) whereas the other had severe respiratory symptoms requiring a stay at an intensive care unit (ICU) and treatment with remdesivir and dexamethasone. Despite their difference in clinical courses, they both continuously shed SARS-CoV-2 with high viral loads in culture. Both patients had undetectable anti SARS-CoV-2 IgG levels about 2 weeks after the first positive real time RT-PCR test of SARS-CoV-2, marked expansions of virus reactive CD8+ T cells but cellular markers indicative of attenuated humoral immunity.CONCLUSIONS: Our case illustrates the importance of distinguishing isolation guidelines for patients infected with SARS-CoV-2 according to their immunological status. Furthermore, it demonstrates the need for immune markers relating to viral shedding in immunocompromised patients.</p

Evidence of perturbed germinal center dynamics, but preserved antibody diversity, in end-stage renal disease

INTRODUCTION: End-stage renal disease (ESRD) is associated with increased infectious susceptibility and with reduced vaccine responses consistent with compromised humoral immunity. Whether the compromised humoral immunity is due to reduced antibody diversity (reduced somatic hypermutation [SHM]) or altered germinal center (GC) dynamics is not known. The GC-derived chemokine CXCL13 as well as peripheral T follicular helper cells (pTFH) reflect GC dynamics, but have, similar to SHM, never been characterized in relation to ESRD.METHODS: Serum CXCL 13 was determined by ELISA. PTFH were flow-cytometrically defined as CD4+ CD45RA- CCR7+ CXCR5+ lymphocytes. Apoptotic lymphocyte subsets were in addition annexin V+. SHM was determined, by next-generation sequencing and bioinformatics, as nucleotide mutations within the IgG VH (comprising the important antigen-binding domains of IgG, CDR1, and CDR2).RESULTS: Elevated CXCL13 levels characterized ESRD (n = 19; [median] 90 pg/ml, P &lt; 0.01) (controls, n = 18; 62 pg/ml). ESRD pTFH frequencies (n = 19; 11.6% [of CD4+ memory T cells], P &lt; 0.02*, *Bonferroni corrected) (controls, n = 22; 14.9%) and concentrations (n = 19; 0.03 × 109/L, P &lt; 0.02*) (controls, n = 22; 0.07 × 109/L) were reduced. ESRD pTFH were more apoptotic (n = 9; 25.7%, P = 0.04*) (controls, n = 10; 15.9%). SHM did not discriminate between ESRD (n = 10; 7.4%, P = 0.21) and controls (n = 10; 8.4%).CONCLUSIONS: Elevated CXCL13 levels, reduced pTFH levels, and increased pTFH apoptosis suggest that perturbed GC dynamics, and not reduced antibody diversity, underlie the diminished vaccine responses and the compromised humoral immunity in ESRD. However, largely preserved SHM provides a rationale for pursuing vaccination in relation to ESRD.</p

Potential anti-EBV effects associated with elevated interleukin-21 levels:a case report

Background: Germinal center derived memory B cells and plasma cells constitute, in health and during EBV reactivation, the largest functional EBV reservoir. Hence, by reducing germinal center derived formation of memory B cells and plasma cells, EBV loads may be reduced. Animal and in-vitro models have shown that IL-21 can support memory B and plasma cell formation and thereby potentially contribute to EBV persistence. However, IL-21 also displays anti-viral effects, as mice models have shown that CD4+ T cell produced IL-21 is critical for the differentiation, function and survival of anti-viral CD8+ T cells able to contain chronic virus infections. Case presentation: We present immunological work-up (flow-cytometry, ELISA and genetics) related to a patient suffering from a condition resembling B cell chronic active EBV infection, albeit with moderately elevated EBV copy numbers. No mutations in genes associated with EBV disease, common variable immunodeficiency or pertaining to the IL-21 signaling pathway (including hypermorphic IL-21 mutations) were found. Increased (&gt; 5-fold increase 7 days post-vaccination) CD4+ T cell produced (p &lt; 0.01) and extracellular IL-21 levels characterized our patient and coexisted with: CD8+ lymphopenia, B lymphopenia, hypogammaglobulinemia, compromised memory B cell differentiation, absent induction of B-cell lymphoma 6 protein (Bcl-6) dependent peripheral follicular helper T cells (pTFH, p = 0.01), reduced frequencies of peripheral CD4+ Bcl-6+ T cells (p = 0.05), compromised plasmablast differentiation (reduced protein vaccine responses (p &lt; 0.001) as well as reduced Treg frequencies. Supporting IL-21 mediated suppression of pTFH formation, pTFH and CD4+ IL-21+ frequencies were strongly inversely correlated, prior to and after vaccination, in the patient and in controls, Spearman’s rho: − 0.86, p &lt; 0.001. Conclusions: To the best of our knowledge, this is the first report of elevated CD4+ IL-21+ T cell frequencies in human EBV disease. IL-21 overproduction may, apart from driving T cell mediated anti-EBV responses, disrupt germinal center derived memory B cell and plasma cell formation, and thereby contribute to EBV disease control.</p

Culturing of SARS-CoV-2 from patient samples:Protocol for optimal virus recovery and assessment of infectious viral load

Optimal sampling, preservation, and culturing of SARS-CoV-2 from COVID-19 patients are critical for successful recovery of virus isolates and to accurately estimate contagiousness of the patient. In this study, we investigated the influence of the type of sampling media, storage time, freezing conditions, sterile filtration, and combinations of these to determine the optimal pre-analytic conditions for virus recovery and estimation of infectious viral load in COVID-19 patients. Further, we investigated the viral shedding kinetics and mucosal antibody response in 38 COVID-19 hospitalized patients. We found Universal Transport Medium (Copan) to be the most optimal medium for preservation of SARS-CoV-2 infectivity. Our data showed that the probability of a positive viral culture was strongly correlated to Ct values, however some samples did not follow the general trend. We found a significant correlation between plaque forming units and levels of mucosal antibodies and found that high levels of mucosal antibodies correlated with reduced chance of isolating the virus. Our data reveals essential parameters to consider from specimen collection over storage to culturing technique for optimal chance of isolating SARS-CoV-2 and accurately estimating patient contagiousness.</p

Whole-blood culture-derived cytokine combinations for the diagnosis of tuberculosis

Introduction: The diagnosis of tuberculosis (TB) disease and TB infection (TBI) remains a challenge, and there is a need for non-invasive and blood-based methods to differentiate TB from conditions mimicking TB (CMTB), TBI, and healthy controls (HC). We aimed to determine whether combination of cytokines and established biomarkers could discriminate between 1) TB and CMTB 2) TB and TBI 3) TBI and HC. Methods: We used hemoglobin, total white blood cell count, neutrophils, monocytes, C-reactive protein, and ten Meso Scale Discovery analyzed cytokines (interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, interferon (IFN)-ɣ, and tumor necrosis factor (TNF)-α) in TruCulture whole blood tubes stimulated by lipopolysaccharides (LPS), zymosan (ZYM), anti-CD3/28 (CD3), and unstimulated (Null) to develop three index tests able to differentiate TB from CMTB and TBI, and TBI from HC. Results: In 52 persons with CMTB (n=9), TB (n=23), TBI (n=10), and HC (n=10), a combination of cytokines (LPS-IFN-ɣ, ZYM-IFN-ɣ, ZYM-TNF-α, ZYM-IL-1β, LPS-IL-4, and ZYM-IL-6) and neutrophil count could differentiate TB from CMTB with a sensitivity of 52.2% (95% CI: 30.9%-73.4%) and a specificity of 100 % (66.4%-100%). Null- IFN-ɣ, Null-IL-8, CD3-IL-6, CD3-IL-8, CD3-IL-13, and ZYM IL-1b discriminated TB from TBI with a sensitivity of 73.9% (56.5% - 91.3%) and a specificity of 100% (69.2-100). Cytokines and established biomarkers failed to differentiate TBI from HC with ≥ 98% specificity. Discussion: Selected cytokines may serve as blood-based add-on tests to detect TB in a low-endemic setting, although these results need to be validated.</p

A retrospective cohort study of patients with eosinophilia referred to a tertiary centre

Introduction. Patients with eosinophilia (an increased number of eosinophilic granulocytes &gt; 0.5 × 109/l in the blood) are encountered in all medical specialties and frequently need thorough workup to identify the eliciting causes and decide whether treatment is indicated. In Denmark, highly specialised centres for eosinophilic diseases or conditions have been established to provide a foundation for the management of complicated cases. Here, we present experiences from such a multidisciplinary centre. Methods. This was a retrospective study of all patients seen in our tertiary centre for eosinophilia in the 2016-2019 period. Results. Referrals mainly derived from specialised secondary care and to a lesser degree from primary care physicians. Patients were either asymptomatic or exhibited symptoms from up to three organ systems and presented a median eosinophil count of 1.7 × 109/l. Up to eight new clonality analyses or imaging studies per patient were performed after referral. One of these, T-cell receptor analysis, was performed frequently but provided limited information, whereas, e.g., flow cytometry proved more clinically applicable owing to its broader diagnostic range. In total, 51 patients were evaluated and classified as secondary (59%), myeloid neoplasm with PDGFRA rearrangement (2%), idiopathic hypereosinophilic syndrome (31%) and idiopathic hypereosinophilia (8%). Conclusion. The value of a multidisciplinary and versatile approach in a highly specialised centre has a positive impact on diagnostic processes as well as on the evaluation of treatment need.</p