Unswitched memory B cell deficiency in children with sickle cell disease and response to pneumococcal polysaccharide vaccine.

Early mortality in sickle cell disease (SCD) is attributed to increased infections due to loss of splenic function. Marginal zone B cells are important for initial opsonization of pathogens and can be absent in spleen histopathology in SCD. The frequency of unswitched memory B cells (UMBC), the circulating correlate of marginal zone B cells, reflects the immunologic function of the spleen. We hypothesized that asplenia in SCD is associated with alterations in the peripheral blood lymphocyte population and explored whether UMBC deficiency was associated with a clinical phenotype. We analyzed B cell subsets and clinical history for 238 children with SCD and 63 controls. The median proportion of UMBCs was lower in children with SCD compared with controls (4.7% vs. 6.6%, p < .001). Naïve B cells were higher in SCD compared with controls (80.6 vs. 76.3%, respectively, p = .02). UMBC frequency declined by 3.4% per year increase in age in SCD (95% CI: 2%, 4.7%, p < .001), but not in controls. A majority of children in all cohorts had an IgM concentration in the normal range for age and there were no differences between groups (p = .13). Subjects developed titers adequate for long-term protection to fewer serotypes in the polysaccharide vaccine than controls (14.7 vs. 19.4, p < .001). In this cohort, bacteremia was rare and specific clinical complications were not associated with UMBC proportion. In summary, UMBC deficiency occurs in SCD and is associated with age. Future studies should investigate B cell subsets prospectively and identify the mechanism of B cell loss in the spleen.

Screening and Analysis of SARS-CoV-2 Antibody Among Unvaccinated Blood Donors in Chongqing, China.

OBJECTIVE: To investigate the rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody among unvaccinated voluntary blood donors in Chongqing, and to provide evidence for epidemic surveillance. METHODS: A total of 10,208 voluntary blood donors from January 5 to January 20, 2021, in the Chongqing area were collected, and the SARS-CoV-2 immunoglobulin (Ig) G and IgM antibodies were detected by chemiluminescence, and the differences of antibody-positive rate in different gender, age, ABO blood group, and different risk areas were analyzed. RESULTS: Among 10208 blood donors, 10 were found to be positive for SARS-COV-2 IgG antibody, giving a positivity rate of SARS-COV-2 IgG at 0.10%, and 29 were positive for SARS-CoV-2 IgM antibody, with a positivity rate of SARS-CoV-2 IgM at 0.28%. There was no statistical difference in the positive rate of antibody among different genders, ages, and ABO blood types, but it was related to the number of confirmed coronavirus disease 2019 (COVID-19) cases in each city. CONCLUSIONS: The SARS-CoV-2 seroprevalence rate in Chongqing was low and correlated with the number of confirmed COVID-19 cases.

Distinct clinical features of transplanted children with Parvovirus B19 infection.

BACKGROUND: The immature and suppressed immune response makes transplanted children a special susceptible group to Parvovirus B19 (PVB19). However, the clinical features of transplanted children with PVB19 infection haven't been comprehensively described. METHODS: We searched the medical records of all the transplant recipients who attended the Children's Hospital of Fudan University from 1 Oct 2020 to 31 May 2023, and reviewed the medical literature for PVB19 infection cases among transplanted children. RESULTS: A total of 10 cases of PVB19 infection were identified in 201 transplanted children at our hospital, and the medical records of each of these cases were shown. Also, we retrieved 40 cases of PVB19 infection among transplanted children from the literature, thus summarizing a total of 50 unique cases of PVB19 infection. The median time to the first positive PVB19 DNA detection was 14 weeks post-transplantation. PVB19 IgM and IgG were detected in merely 26% and 24% of the children, respectively. The incidence of graft loss/dysfunction was as high as 36%. Hematopoietic stem cell transplant (HSCT) recipients showed higher PVB19 load, lower HGB level, greater platelet damage, lower PVB19 IgM/IgG positive rates, and more graft dysfunction than solid-organ transplant (SOT) recipients, indicating a more incompetent immune system. CONCLUSIONS: Compared with the published data of transplanted adults, transplanted children displayed distinct clinical features upon PVB19 infection, including lower PVB19 IgM/IgG positive rates, more graft dysfunction, and broader damage on hematopoietic cell lines, which was even more prominent in HSCT recipients, thus should be of greater concern.

Major low-energy trauma results in non-specific immunoglobulin generation without evidence for specific autoantibody production: A prospective cohort study.

Cellular debris resulting from large trauma might overwhelm the scavenger mechanisms and lead to autoimmune reactions. We analysed whether a major well-defined trauma in humans induces laboratory signs of transient autoimmunity in the months after the insult. We included 50 patients with pertrochanteric femur fracture undergoing intramedullary nail osteosynthesis in a prospective cohort study and followed them at 3-4 days, 6 weeks, 12 weeks and 12 months postoperatively. By standard techniques, we assessed levels of total immunoglobulins, anti-nuclear antibodies (ANA), anti-cardiolipin antibodies, anti-dsDNA antibodies and anti-C1q antibodies, as well as antibodies against cytomegalovirus (CMV) as a control. Blood leukocyte differential and lymphocyte subpopulations were determined at baseline and in the first two postoperative samples. The mean age of the patients reached 80.1 years, and 23 (46%) completed all visits. Serum concentrations of total IgG, IgM and IgA increased at all follow-up time points. The ANA fluorescence light intensity units increased at 12 weeks and 12 months postoperatively (p < 0.0001), but the proportion of ANA-positive patients did not change (35%). The values of anti-C1q mildly increased at all follow-up visits, but not the ratio to total IgG. Anti-dsDNA remained negative in all patients, and anti-cardiolipin IgG/IgM antibodies did not change. Anti-CMV IgG antibodies increased significantly at all follow-up visits, without change in the ratio to total IgG. Flow cytometry showed an increased proportion of B-cells 3-4 days postoperatively. In conclusion, major musculoskeletal trauma in elderly patients induces a generalized non-specific increase in immunoglobulin production without laboratory signs for enhanced systemic autoimmunity.

Lymphocyte B Subtypes in Peripheral Blood: A Prognostic Biomarker for COVID-19 Patients.

BACKGROUND: In view of the scientific gap in knowledge of the involvement of the B-cell compartment and clinical prognostic in SARS-CoV-2 infection, this work aims to evaluate the B-cell subsets and the presence of specific IgM and IgG, as well as neutralizing antibodies against SARS-CoV-2, in unvaccinated patients diagnosed with COVID-19. METHODS: This study included 133 patients with COVID-19. Cellular components were assessed by flow cytometry, and immunoglobulin levels and reactivity were measured by indirect enzyme-linked immunosorbent assay. RESULTS: Our results showed no changes in less differentiated B cells. However, non-switched memory B cells (NS-MBCs) and class-switched memory B cells (CS-MBCs) were reduced in the patients with moderate disease. Also, plasmablasts and double-negative (DN) or "atypical" memory B cells were increased in groups of patients with moderate to critical conditions. In addition, the production of IgM, IgG, and neutralizing antibodies against SARS-CoV-2 demonstrated a positive correlation between the positivity of antibodies against SARS-CoV-2 and disease severity. Besides being related to the development of a more severe course of the disease, the increase in DN B-cell count also contributed to a poorer disease outcome in patients with a higher percentage of these cells. On the other hand, we observed an increase in the absolute number of CS-MBCs in patients with greater chances of survival. CONCLUSIONS: This study demonstrates that the B-cell compartment may contribute to the development of clinical symptoms of COVID-19, with changes in B-cell subset counts linked to disease course and patient prognosis.

A Case of Idiopathic Orbital Inflammation With Elevated Anti-Mumps Immunoglobulin M Antibody.

A 21-year-old female presented with periocular swelling, diplopia, and painful ophthalmoplegia in the OS. Orbital magnetic resonance imaging revealed an enhanced soft tissue mass involving the left medial rectus muscle. Laboratory test results revealed leukocytosis, elevated reactive C-reactive protein, and positive serum levels of anti-mumps immunoglobulin M (IgM) antibody without systemic manifestations of mumps infection. The clinical course was refractory, and the patient showed a poor response to high-dose steroids. An incisional biopsy revealed stromal fibrosis with focal lymphoid aggregates, indicating sclerosing inflammation. Myopathy of the medial rectus progressed to superior, inferior, and lateral recti involvement of the left orbit. Immunosuppressive agents, including steroids, were administered for 22 months after disease onset. The mumps IgM antibody level was positive for over 5 months and became negative upon testing performed 1 year after the first visit.

A report of three cases of patients with tubulointerstitial nephritis with IgM-positive plasma cells, treatment, and serum-IgM as a sensitive marker for relapse.

BACKGROUND: Tubulointerstitial nephritis with IgM-positive plasma cells (IgMPC-TIN) is a newer disease about which there are many unclear points. Glucocorticoid therapy is effective in many cases of IgMPC-TIN; however, relapse during glucocorticoid tapering has been reported. Relapse and its treatment are poorly defined. CASE PRESENTATION: Case 1 was a 61-year-old man with renal dysfunction and proteinuria. Tubulointerstitial nephritis and IgM-positive plasma cells were observed in a renal biopsy. He was diagnosed with IgMPC-TIN accompanied by Fanconi syndrome and distal renal tubular acidosis (d-RTA). Prednisolone (PSL; 30 mg daily, 0.45 mg/kg/day) treatment was highly effective, and PSL was gradually tapered and discontinued after 1 year. However, 1 month after PSL discontinuation, therapeutic markers were elevated. Therefore, PSL (10 mg daily, 0.15 mg/kg/day) was administered, and the markers indicated improvement. Case 2 was a 43-year-old woman referred for renal dysfunction and proteinuria. Laboratory data revealed that she had primary biliary cholangitis (PBC), d-RTA, and Fanconi syndrome. A renal biopsy showed accumulation of IgM-positive plasma cells in the tubulointerstitium without any glomerular changes. A diagnosis of IgMPC-TIN was made and the patient was started on PSL (35 mg daily, 0.6 mg/kg/day). Therapeutic markers decreased immediately and PSL was discontinued after 1 year. Three months later, the proteinuria and Fanconi syndrome worsened. PSL treatment was restarted (20 mg daily, 0.35 mg/kg/day) and markers indicated improvement. Case 3 was a 45-year-old woman with renal dysfunction and proteinuria. Tubulointerstitial nephritis and IgM-positive plasma cells were observed in a renal biopsy. The patient had PBC, Sjögren syndrome, d-RTA, and Fanconi syndrome, and the diagnosis of IgMPC-TIN was made. The patient was started on PSL (30 mg daily, 0.4 mg/kg/day) and disease markers decreased immediately. However, when PSL was tapered to 15 mg daily (0.2 mg/kg/day), the patient's serum IgM levels increased; therefore, we maintained the PSL at 15 mg daily (0.2 mg/kg/day). CONCLUSION: We report three cases of relapsed IgMPC-TIN associated with reduction or discontinuation of glucocorticoid therapy. In these cases, elevation of serum IgM preceded that of other markers such as urinary ß2-microglobulin, proteinuria, and glycosuria. We recommend monitoring serum IgM levels while tapering glucocorticoids; a maintenance dose of glucocorticoid should be considered if relapse is suspected or anticipated.

Monitoreo serológico y psicológico en personal de salud durante el comienzo de la pandemia COVID-19 / Serological and psychological monitoring of healthcare workers during the start of the COVID-19 pandemic

Introducción: el personal de salud (PdS) es esencial en la lucha contra el COVID-19. Al inicio de la pandemia, el riesgo de adquirir la enfermedad en este grupo era desconocido. Buscamos estimar incidencia y prevalencia de anticuerpos anti-SARS-CoV-2, y prevalencia de burnout en una cohorte de PdS durante la pandemia COVID-19, así como valorar la prevalencia de burnout y depresión en la cohorte. Materiales y métodos: cohorte prospectiva conformada por médicos que atendían pacientes COVID-19 desde marzo de 2020 hasta enero de 2021, en un hospital de alta complejidad de la ciudad de Buenos Aires. Se evaluó IgM e IgG anti-SARS-CoV-2 quincenalmente durante 3 meses, así como la presencia de síntomas compatibles y factores asociados a la exposición. Se remitió a participantes con alteraciones de la esfera psíquica a contacto con el equipo de salud mental del hospital. Resultados: se incluyeron 52 participantes; de ellos, 31 eran mujeres; mediana de edad 32 años (rango 25-58). La mediana de horas semanales de trabajo autoinformadas fue 48 (IIC [intervalo intercuartil] 40-69,5). Inicialmente todos fueron PCR SARS-CoV-2 negativos en hisopado nasal; 11 (21,50% IC 95%; 9,62-32,53%) tuvieron COVID-19 sintomático con anticuerpos positivos. Los factores con mayor asociación a riesgo de COVID-19 fueron anosmia/disgeusia OR 403,33 (IC 95%; 47,60-3417,02), fiebre OR 172,53 (IC 95%; 28,82-1032,65), mialgias OR 41,97 (IC 95%; 8,08-217,84), conviviente con COVID-19 OR 28,17 (IC 95%; 5,67-179,97). Cerca del 40% presentaba alteraciones en las escalas de medición de burnout o depresión. Discusión: la incidencia hallada coincide con las cifras informadas acerca de personal de salud en la etapa inicial de la pandemia en la Argentina. Otro aspecto similar fue una mayoría de infecciones de curso leve, sin ningún paciente hospitalizado. No obstante, se halló una elevada incidencia de alteraciones de la esfera psíquica, tanto al comienzo como al final del seguimiento. Conclusiones: la incidencia de positivización de anticuerpos anti-SARS-CoV-2 fue cercana al 20%. No evidenciamos infecciones presintomáticas o asintomáticas. En cambio, la prevalencia de burnout y depresión fue elevada. La salud mental es un componente del personal de salud que debe ser priorizado en situaciones futuras de impacto similar. (AU)

Introduction: healthcare personnel are essential in the response against COVID-19. At the beginning of the pandemic the risk of acquiring the disease in this group was unknown. We sought to estimate incidence and prevalence of anti SARS-CoV-2 antibodies, as well as burnout prevalence in a cohort of healthcare staff during the pandemic, as well as assessing the prevalence of burnout and depression in this group. Materials and methods: prospective cohort formed by physicians tending to COVID-19 patients from march 2020 to january 2021 in a high-complexity hospital in the city of Buenos Aires. We evaluated anti SARS-CoV-2 IgM and IgG each 15 days for 3 months as well as the presence of compatible symptoms and factors associated to exposition to the virus. Patients showing signs of burnout and/or depression were referred to proper care by the mental health team in the hospital. Results: we included 52 patients, 31 women, median age was 32 years (range 25 - 58). Median amount of self-reported hours worked each week was 48 (IQR 40 - 69.5). Initially all participants had a negative COVID-19 PCR nasopharyngeal swab; 11 (21.50% CI95% 9.62 - 32.53%) had symptomatic COVID-19 with positive antibodies. Factors showing stronger association with testing positive were anosmia/dysgeusia OR 403.33 (CI95% 47.60-3417.02), fever OR 172.53 (CI95% 28.82 - 1032.65), myalgia OR 41.97 (CI95% 8.08 - 217.84), cohabitation with confirmed COVID-19 case OR 28.17 (CI95% 5.67 - 179.97). Near 40% showed alterations in burnout or depression scales. Discussion: the incidence rate we found was like reported values in the initial stages of the pandemic in Argentina. Another similarity was that all cases were mild; no hospitalization was required for any participant. We found an elevated incidence of alterations in the psychic sphere, both at the beginning and end of the follow up period. Conclusions:the incidence of positive SARS-CoV-2 antibodies was around 20%. No pre or asymptomatic cases were identified. Burnout and depression incidence was high. Mental health is a component that should never be overlooked in similar situations to come. (AU)

SARS-CoV-2-specific antibody response characteristics in COVID-19 patients of different ages.

Age has been found to be one of the main risk factors for the severity and outcome of COVID-19. However, differences in SARS-CoV-2 specific antibody responses among COVID-19 patients of different age groups remain largely unknown. In this study, we analyzed the IgG/IgM responses to 21 SARS-CoV-2 proteins and 197 peptides that fully cover the spike protein against 731 sera collected from 731 COVID-19 patients aged from 1 to We show that there is no overall difference in SARS-CoV-2 antibody responses in COVID-19 patients in the 4 age groups. By antibody response landscape maps, we find that the IgG response profiles of SARS-CoV-2 proteins are positively correlated with age. The S protein linear epitope map shows that the immunogenicity of the S-protein peptides is related to peptide sequence, disease severity and age of the COVID-19 patients. Furthermore, the enrichment analysis indicates that low S1 IgG responses are enriched in patients aged <50 and high S1 IgG responses are enriched in mild COVID-19 patients aged >60. In addition, high responses of non-structural/accessory proteins are enriched in severe COVID-19 patients aged >70. These results suggest the distinct immune response of IgG/IgM to each SARS-CoV-2 protein in patients of different age, which may facilitate a deeper understanding of the immune responses in COVID-19 patients.

[Analysis of serum immunoglobulin level in children with Burkitt lymphoma].

Objective: To summarize changes of serum immunoglobulin levels before and after chemotherapy in children with Burkitt lymphoma (BL), so as to investigate the effects of chemotherapy and rituximab on serum immunoglobulin levels in children with BL. Methods: Clinical data of 223 children with newly diagnosed Burkitt lymphoma at Beijing Children's Hospital from January 2009 to April 2017 were analyzed retrospectively. They were treated according to the modified LMB 89 regimen and some of them received combined rituximab therapy during the chemotherapy. The serum immunoglobulin (IgA, IgM, IgG) before chemotherapy, at the time of discontinuing chemotherapy, as well as 6, 12, 24, 36 months after chemotherapy were collected. Changes of serum IgA, IgM and IgG with time among different treatment groups were compared using repeated measures ANOVA. Results: According to risk group, 223 children were devided into group B（n=53）and group C（n=170）. Before chemotherapy, 109 cases (48.9%) were combined with hypogammaglobulinemia. The serum IgA, IgM, and IgG levels of all the patients were (0.9±0.7), 1.2 (0.5, 1.3) and (7.2±2.9) g/L before chemotherapy, (0.5±0.4), 0.2 (0.1, 0.3) and (6.3±2.3) g/L at the time of discontinuing chemotherapy (t=13.63, Z=-11.99, t=4.57, all P<0.05). There were statistical difference in IgA, IgM levels of group B and IgA, IgM, IgG levels of group C before chemotherapy and at the time of discontinuing chemotherapy (t=8.86, Z=-6.28, t=11.19, Z=-10.15, t=4.50, all P<0.05). The differences of serum IgA and IgG levels at the time after chemotherapy among patients treated with chemotherapy alone and those treated with chemotherapy combined rituximab in group B and C were significant (F=5.38, P=0.002 and F=4.22, P=0.007). Conclusions: Approximately half of children with BL have already existed hypogammaglobulinemia at initial diagnosis prior to the start of treatment. The modified LMB 89 regimen have significant effect on humoral immunity of children with BL. In the process of immune reconstruction after chemotherapy, rituximab has more significant effect on serum IgA and IgG levels in BL patients.

COVID-19 IgG/IgM patterns, early IL-6 elevation and long-term radiological sequelae in 75 patients hospitalized due to interstitial pneumonia followed up from 3 to 12 months.

BACKGROUND: COVID-19 pandemic resulted in about 165 million infections and 3.4 million deaths all over the world across 15 months. The most severe clinical presentation of COVID-19 diseases is interstitial pneumonia. METHODS: In this paper we describe clinical outcomes based on radiological features as well as the pattern of haematochemical parameters and IgG/IgM antibodies in 75 patients hospitalized due to COVID-related interstitial pneumonia not requiring intensive care assistance. Each patient underwent routine laboratory tests, including inflammatory markers and coagulation profile at baseline. Computed Tomography (CT) was performed at baseline and after 3 months to assess the persistence of radiological sequelae. A Generalized Linear Model (GLM) was used to test for each patient the association between individual haematochemical parameters at the time of hospital admission and the subsequent radiological features after three months. The presence of IgG antibodies was quantitatively determined in 70 patients at the time of hospital admission and after 3 months. A subgroup of 49 and 21 patients underwent additional dosage of IgG after 6 and 12 months, respectively. IgM serological antibodies were available for 17 patients at baseline and 61 at T3, with additional follow-up for 51 and 20 subjects after 6 and 12 months, respectively. RESULTS: Only 28 out of 75 patients discharged from the hospital were totally healed after 3 months, while 47 patients (62.7%) still presented radiological sequelae. According to the GLM model, specific haematochemical baseline parameters-such as IL-6, GPT, platelets and eosinophil count-showed a statistically significant association with the presence of radiological sequelae at month 3 highlighting an OR = 0.5, thus meaning that subjects completely healed after 3 months presented half levels of IL-6 at baseline compared to patients with sequelae. In general, IgG serum levels were always higher than IgM at the time of hospitalization (75% at T0; n = 12 out of 16 patients with data available in both visits), after 3 months (72.1%; n = 44 out of 61 pts.), after 6 months (56.8%; 25 out of 44 pts.), and one year after hospitalization (60%; 12 out of 20 pts.). Overall, IgG and IgM serum levels presented a statistically significant decreasing trend from the baseline to month 3, 6 and 12. One patient presented an increase in IgM between baseline and month 3 but negative PCR test for SARS-COV2 on throat swab. CONCLUSIONS: As supported by our findings on 75 patients, COVID-related interstitial pneumonia triggers early IgG levels (higher than IgM) that gradually decrease over 12 months. Mid-term sequelae are still detectable at lung Computed Tomography after 3 months from the hospital admission. Occasionally, it is possible to observe increase of IgM levels in presence of low concentrations of IgG and negative PCR ELISA tests for SARS-COV2 RNA. Baseline levels of IL-6 could be proposed as predictor of radiological mid/long-term sequelae after COVID-related interstitial pneumonia.

Hypersensitivity reactions to asparaginase therapy in acute lymphoblastic leukemia: immunology and clinical consequences.

Asparaginase is commonly used in combination therapy of acute lymphoblastic leukemia. However, as an immunogenic protein, hypersensitivity reactions (HSRs) during asparaginase therapy are frequent, indicating the development of anti-asparaginase antibodies. These can be associated with diminished clinical effectiveness, including poorer survival. Therapeutic drug monitoring of serum asparaginase activity to confirm complete asparagine depletion is therefore crucial during asparaginase therapy. Switching to alternative types of asparaginase is recommended for patients experiencing HSRs or silent inactivation; those with HSRs or silent inactivation on Escherichia coli-derived asparaginases should switch to another preparation. However, prior global shortages of Erwinia asparaginase highlight the importance of alternative non-E. coli-derived asparaginase, including recombinant Erwinia asparaginase.

Asparaginase is commonly used as a part of a multidrug regimen for acute lymphoblastic leukemia treatment. As foreign proteins, asparaginases have the potential to induce immune responses known as hypersensitivity reactions (HSRs), which can range from a mild rash to a severe allergic reaction. Here, we provide an overview of HSRs and their prevalence in asparaginase-based therapies, and clinical approaches to reduce HSRs. We also review the current understanding of cellular and molecular mechanisms of HSRs, consequences of HSRs and current recommendations for the management of immune reactions to asparaginase. Prior global shortages of Erwinia asparaginase due to manufacturing and supply issues have limited access of asparaginase treatment to patients. In this context, newer therapies have recently been developed.

Peptide Biomarkers for the Diagnosis of Dengue Infection.

In a world with an increasing population at risk of exposure to arthropod-borne flaviviruses, access to timely and accurate diagnostic tests would impact profoundly on the management of cases. Twenty peptides previously identified using a flavivirus proteome-wide microarray were evaluated to determine their discriminatory potential to detect dengue virus (DENV) infection. This included nine peptides recognized by IgM antibodies (PM peptides) and 11 peptides recognized by IgG antibodies (PG peptides). A bead-based multiplex peptide immunoassay (MPIA) using the Luminex technology was set-up to determine Ab binding levels to each of these peptides in a panel of 323 carefully selected human serum samples. Sera are derived from individuals either infected with different viruses, namely, the four DENV serotypes, Zika virus (ZIKV), yellow fever virus (YFV), chikungunya virus (CHIKV), West Nile virus (WNV) and Human immunodeficiency virus (HIV), or receiving vaccination against YFV, tick-borne encephalitis (TBEV), and Japanese encephalitis virus (JEV). Additionally, a set of healthy controls were included. We targeted a minimum specificity of 80% for all the analysis. The PG-9 peptide had the best sensitivity (73%) when testing DENV sera from acute patients (A-DENV; <8 days since symptom onset). With sera from convalescent DENV patients (C-DENV; >10 days since symptom onset) the FPG-1 peptide was the best seromarker with a sensitivity of 86%. When combining all A-DENV and C-DENV samples, peptides PM-22 and FPG-1 had the best-diagnostic performance with a sensitivity of 60 and 61.1%, and areas under the curve (AUC) of 0.7865 and 0.8131, respectively. A Random forest (RF) algorithm was used to select the best combination of peptides to classify DENV infection at a targeted specificity >80%. The best RF model for PM peptides that included A-DENV and C-DENV samples, reached a sensitivity of 72.3%, while for PG peptides, the best RF models for A-DENV only, C-DENV only and A-DENV + C-DENV reached a sensitivity of 88.9%, 89.1%, and 88.3%, respectively. In conclusion, the combination of multiple peptides constitutes a founding set of seromarkers for the discrimination of DENV infected individuals from other flavivirus infections.

High levels of autoantibodies against apoB100 p210 are associated with lower incidence of atrial fibrillation in women.

BACKGROUND AND OBJECTIVES: Atrial fibrillation (AF) is associated with inflammation, both systemically and in the atrial tissue. Oxidized low-density lipoprotein (LDL) is increased in patients with AF and is suggested to be one of the molecules that drives inflammation. Autoantibodies against oxidized LDL and apolipoprotein B100, the protein component of LDL, are linked to atherosclerotic disease. However, whether these autoantibodies are associated with occurrence of AF is not known. We investigated autoantibodies against oxidized apolipoprotein B100 peptides and incidence of AF in a large population-based cohort. METHODS: IgM and IgG against native and aldehyde-modified apoB100 peptides 210 (p210) and 45 were analyzed by enzyme-linked immunosorbent assay (ELISA) in 5169 individuals from the Malmö Diet and Cancer cohort. RESULTS: Seven hundred sixty-nine incident AF cases were recorded during a follow-up of 21.3 years. Individuals with high levels of IgM against native p210 at baseline had a lower risk of developing AF; however, the association did not remain after adjustment for age and sex. Women had higher levels of IgM against native p210 than men (0.70 ± 0.22 AU vs. 0.63 ± 0.21 AU, p < 0.001). The association of IgM against native p210 and AF was significantly different between sexes (p for interaction = 0.024), where females with high IgM against p210 had a lower risk for incidence of AF (hazard ratio [95% confidence interval] 4th versus 1st quartile: 0.67 [0.49-0.91]; p = 0.01) after adjusting for risk factors and comorbidities. CONCLUSION: These findings support an association of humoral autoimmunity with AF.

Circulating anti-human leukocyte antigen IgM antibodies as a potential early predictor of allograft rejection and a negative clinical outcome after lung transplantation.

PURPOSE: Anti-human leukocyte antigen (HLA) immunoglobulin (Ig) M production stimulated by an alloantigen is sensitive, making IgM a novel potential marker of allorejection after organ transplantation. This study examined the relationship between the serum levels of anti-HLA IgM early after clinical lung transplantation (LTx) and the post-transplant outcomes. METHODS: Thirty-one consecutive patients who underwent deceased LTx were included. Immunoreactivity against HLA was retrospectively analyzed by measuring the anti-HLA IgM levels in the serum sampled for the first 14 days after LTx. The flow panel reactive antibody technique was used. The ratio of the anti-class I IgM level at each day to baseline was obtained, and the peak IgM level was determined for each case. The correlation between the peak IgM level and subsequent development of acute rejection (AR), chronic lung allograft dysfunction (CLAD), and survival outcomes were examined. RESULTS: The peak IgM level was a significant risk factor for AR within 90 days in univariate and multivariate analyses. In the long term, the patients with positive IgM (peak level > 1.8) tended to have a poorer CLAD-free and overall survival than those with negative IgM. CONCLUSION: Elevation of anti-HLA IgM levels early after LTx may be correlated with a higher incidence of rejection and negative clinical outcomes.

Public screening for COVID-19 in Wuhan, China and beware of the antibody positive in women and tumor patients.

The novel coronavirus disease 2019 (COVID-19) has become a global health emergency. Early detection and intervention are key factors for improving outcomes in patients with COVID-19. Real-time reverse transcriptase polymerase chain reaction-based molecular assays and antibody for detecting SARS-CoV-2 in respiratory specimens are the current reference standard for COVID-19 diagnosis. Clinical implications of different specimen types for nucleic acid and antibody testing of COVID-19 in Zhongnan hospital of Wuhan University were analyzed. Compared with health groups, tumor patients had higher rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (+/-) immunoglobulin M (IgM) (+) immunoglobulin G (IgG) (+). The rate of SARS-CoV-2 (-) IgM (+) IgG (-) or SARS-CoV-2 (-) IgM (-) IgG (+) in female was significantly higher than that in male. These results can help governments to take screening measures to prevent the COVID-19 pandemic again.

Effects of nutritional support combined with insulin therapy on serum proteins, inflammatory factors, pentraxin-3, and serum amylase levels in patients with diabetic ketoacidosis complicated with acute pancreatitis.

ABSTRACT: To explore the effects of nutritional support combined with insulin therapy on serum protein, procalcitonin (PCT), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), pentraxin-3 (PTX-3), and serum amylase (AMS) levels in patients with diabetic ketoacidosis complicated with acute pancreatitis.A total of 64 patients with diabetic ketoacidosis complicated with acute pancreatitis admitted to our hospital from January 2018 to February 2019 were enrolled in this prospective study. They were divided into the study group and the control group according to the random number table method, with 32 patients in each group. Patients in the study group were given nutritional support combined with insulin therapy, and patients in the control group were given insulin therapy.There were no significant differences in general data including age, gender, body mass index, course and type of diabetes, acute physiology and chronic health evaluation II, RANSON, CT grades between the 2 groups before treatment (all P > .05). After 7 days of treatment, the clinical efficacy of the study group was significantly higher than that of the control group (study group vs control group, 94.44% vs 75.00%, P < .05). After 7 days of treatment, the levels of prealbumin and albumin in the study group were significantly higher than those in the control group (P < .05). After 7 days of treatment, the levels of PCT, CRP, TNF-α, PTX-3, and AMS in the 2 groups were significantly lower than those before treatment (P < .05), and the levels of PCT, CRP, TNF-α, PTX-3, and AMS in the study group were significantly lower than those in the control group. After 7 days of treatment, the levels of IgG, IgM, and IgA in the 2 groups were significantly higher than those before treatment, and the levels of IgG, IgM, and IgA in the study group were significantly higher than those in the control group (P < .05).Nutritional support combined with insulin is obviously effective in the treatment of diabetic ketoacidosis complicated with acute pancreatitis, which can improve serum protein levels, reduce inflammatory response, improve immune function, and is worthy of clinical application.

Anti-Human Herpesvirus 6 A/B Antibodies Titers Correlate With Multiple Sclerosis-Associated Retrovirus Envelope Expression.

Human endogenous retrovirus W family envelope proteins (pHERV-W ENV/syncytin-1) have been repeatedly associated with multiple sclerosis (MS). Here, we have focused on the study of pHERV-W ENV/syncytin-1 expression levels in MS patients (relapsing and progressive forms) and in healthy donors (HD) and on exploring their possible relationship with Epstein-Barr virus (EBV) and human herpesvirus-6A/B (HHV-6A/B). We included blood samples from 101 MS patients and 37 HD to analyze antiviral antibody titers by ELISA and pHERV-W ENV/syncytin-1 expression levels by flow cytometry as well as by qPCR. Patients with relapsing MS forms showed significantly higher pHERV-W ENV/syncytin-1 protein and gene expression levels than HD. Progressive MS patients also showed significantly higher protein and gene expression levels than both HD and relapsing MS patients. Regarding antiviral antibodies titers, anti-HHV-6A/B IgM levels were positively correlated with pHERV-W ENV/syncytin-1 protein expression levels in patients with relapsing MS, while in the progressive forms patients this correlation was found with anti-HHVA/B IgG levels. Therefore, pHERV-W ENV could be involved in MS pathogenesis, playing a role in relapsing and progressive forms. Besides, anti-HHV-6A/B antibodies positively correlated with pHERV-W ENV expression. Further studies are needed to better understand this possible relationship.

Relationship between plasma cyclin-dependent kinase 5 levels and local immunoglobulin levels in patients with nasal polyps.

Nasal polyps are the most common benign nasal tumors that can lead to nasal obstruction and other annoying problems for the patient. Several hypotheses have been proposed as the basic mechanism of nasal polyps. In order to investigate one of the possible causes that can be a disorder in the regulation of systemic immune responses, the present study was designed to investigate the relationship between plasma cyclin-dependent kinase 5 (CDK5) levels and local immunoglobulin levels in patients with nasal polyps. A cross-section study was used to evaluate concentrations of local immunoglobulin levels (IgE, IgM, IgA, and IgG) on blood and polyp specimens from 60 patients with nasal polyps, and 60 control groups. Western Blot Analysis was done for CDK5 in plasma cells. IgA, IgG and IgE concentrations were significantly higher in polyp tissue specimens, but not in blood, of nasal polyp patients compared to the control group. Furthermore, plasma CDK5 levels were significantly higher in nasal polyp tissue compared with control. The difference in IgA, IgE and IgG expression between nasal polyp tissue and blood, supported by increased numbers of plasma cells, suggests a local production of these local immunoglobulins in nasal polyps in response to chronic antigens. Among local immunoglobulins, only there was a significant correlation between CDK5 with IgG (positive correlation) and IgE (negative correlation). The exact explanation for the relationship between plasma CDK5 and local immunoglobulins in nasal polyps needs further studies.

Routine COVID-19 testing may not be necessary for most cancer patients.

Cancer patients are at risk for severe complications or death from COVID-19 infection. Therefore, the need for routine COVID-19 testing in this population was evaluated. Between 1st August and 30th October 2020, 150 cancer patients were included. Symptoms of COVID-19 infection were evaluated. All eligible individuals went through RT-PCR and serological tests for COVID-19. At the same time, 920 non-cancer patients were recruited from a random sample of individuals who were subject to routine molecular and anti-body screening tests. Of 150 cancer patients, 7 (4.7%) were RT-PCR positive. Comorbidity made a significant difference in the RT-PCR positivity of cancer patients, 71.4% positive versus 25.8% negative (P-value = 0.02). The average age for negative and positive groups was 53.3 and 58.2 respectively (P-value = 0.01). No significant difference was observed between cancer and non-cancer patients regarding COVID-19 antibody tests. However, cancer patients were 3 times less likely to have a positive RT-PCR test result OR = 0.33 (CI: 0.15-0.73). The probability of cancer patients having a positive routine test was significantly lower than non-cancer patients, and the concept that all cancer patients should be routinely tested for COVID-19 may be incorrect. Nevertheless, there may be a subgroup of patients with comorbidities or older age who may benefit from routine COVID-19 testing. Importantly, these results could not be subjected to multivariate analysis.