IgG Levels Research Articles

Effects of dietary Brassica rapa L. polysaccharide on growth performance, immune and antioxidant functions and intestinal flora of yellow-feathered quail.

This study aimed to explore the impact of Brassica rapa L. polysaccharides (BRP) on the growth, immune response, antioxidant capacity, and cecal microbiota in yellow-feathered quails. A total of 250 one-day-old yellow-feathered quails, evenly divided by sex, were randomly assigned to five groups, with each group comprising ten replicates of five quails each. The control group (CON) received a basic diet, while the antibiotic control group (CTC) was fed a basic diet supplemented with chlortetracycline (0.05g/kg). BRP was administered at concentrations of 0.25g/kg (Low dose BRP, LBRP), 0.5g/kg (Medium dose BRP, MBRP), and 1g/kg (High dose BRP, HBRP). The duration of the experiment was 42 days. The results indicated that, compared to the CON group, the final body weight of quails in the MBRP group significantly increased (P < 0.05), and there was a significant difference in body weight between the LBRP group and the CTC group (P < 0.05). At 21 days of age, the average weights of the thymus and bursa of Fabricius in the MBRP group were significantly greater than those in the CON group (P < 0.05), with no significant difference observed when compared to the CTC group (P > 0.05); at 42 days of age, the average weight of the thymus in the MBRP group was significantly greater than that in the CON group (P < 0.05), with no significant difference observed compared to the CTC group (P > 0.05). At 21 days of age, the levels of IgA and IgG in the MBRP group were significantly elevated compared to the CON group (P < 0.05), with no significant difference noted compared to the CTC group (P > 0.05). Additionally, the MBRP group showed significant increases in CAT, T-SOD, and GSH-Px levels (P < 0.05) compared to the CON group; the levels of IL-1β and TNF-α were significantly reduced (P < 0.05), and the level of IL-10 was significantly elevated (P < 0.05) compared to the CON group. Furthermore, 16S rRNA sequencing revealed that BRP supplementation increased the populations of beneficial cecal bacteria such as Lactococcus, Weissella, Parabacteroides, and norank_f_Ruminococcaceae, and decreased the population of the harmful bacterium Campylobacter, indicating that BRP modulates the microbial community structure in the cecum of yellow-feathered quails. In summary, BRP enhanced the growth performance, serum immunoglobulin levels, antioxidant functions, and improved the intestinal microbiota in yellow-feathered quails.

Seroepidemiology of pertussis immunity in five provinces of China: A population-based, cross-sectional study

ABSTRACT This study aimed to evaluate the seroprevalence of Bordetella pertussis and persistence of antibodies following vaccination. We recruited 6060 healthy subjects from five provinces of China during 2017–2018. Serum IgG antibodies against pertussis toxin (anti-PT IgG) and filamentous hemagglutinin (anti-FHA IgG), and serum IgA antibodies against pertussis toxin (anti-PT IgA) were measured by ELISA. Geometric mean concentration (GMC), seropositivity rate, and recent infection rate were calculated. Among 0–6 years-olds, the anti-PT IgG, anti-PT IgA, and anti-FHA IgG GMCs were 6.4 IU/ml (95% CI 6.1–6.8), 2.8 IU/ml (95% CI 2.7–2.8), and 13.3 IU/ml (95% CI 12.4–14.2), respectively. The anti-PT IgG GMC increased in accordance with the primary vaccination series (4–6 months) and the toddler booster (18–24 months), but declined thereafter through to age 5 years [4.7 IU/ml (95% CI 4.2–5.4)]. The seropositivity rate of pertussis in >6 year-olds was 9.0% (95% CI 8.1–9.9) and the recent infection rate was 3.3% (95% CI, 2.7–3.8). Recent infection rate began to increase from 6 years of age, with peaks at 9, 20, 40, and ≥60 years of age. The anti-PT IgG GMCs of children aged 0–6 years who were vaccinated with DTaP, DTaP-IPV//PRP～T, and DTaP-Hib were 5.9 IU/ml (95% CI 5.6–6.3), 20.7 IU/ml (95% CI 15.6–27.8), and 11.7 IU/ml (95% CI 7.5–18.1) (p < .001), respectively (p < .001). Pertussis vaccination improves anti-PT IgG levels, however these wane soon after vaccination. Sero-estimated recent infection rates appear to increase from school age into adolescence and adulthood. Pertussis vaccine boosters should be considered in these age groups.

Rotavirus-specific-IgA and cytokines responses in Ascaris lumbricoides-infected preschool-aged Nigerian children following rotavirus vaccination

ABSTRACT Rotavirus diarrhea and Ascaris lumbricoides (Al) infection increase intestinal morbidity and were associated with altered immune responses that compromise the vaccine efficacy in children. The serum level of rotavirus specific IgA (RV-IgA) and cytokine profiles in A. lumbricoides (AI) infected preschool-aged Nigerian children were estimated following oral rotavirus vaccination. Nineteen of the 149 preschool-aged children (aged 6 to 60 months) with Ascaris lumbricoides infection paired with age and sex-matched helminth – free children were administered with oral rotavirus vaccine after intestinal helminth screening using stool sample concentration technique. Separated sera from 3 mL venous blood samples were collected and estimated for cytokines (IFN–γ, TNF–α, IL-4, IL-8 IL-6, IL-10) and RV-IgA before and three weeks after rotavirus vaccination using Enzyme Linked Immunosorbent Assay. IFN–γ, IL-8, IL-4 were significantly lower at post-vaccination in Al-infected children compared with pre-vaccination. Serum IL-10 was significantly higher at post-vaccination in both Al-infected children and helminth-free controls, compared with pre-vaccination levels (p < 0.05). Pre-vaccination IL-8 and IL-6 were significantly higher in Ascaris lumbricoides–infected children, while the post-vaccination IL-8 was significantly higher in Ascaris lumbricoides–infected compared with control. At post-vaccination period, RV-IgA level was lower in Al-infected children and significantly higher in helminth – free control group compared to pre-vaccination RV-IgA level. Ascaris lumbricoides infection contributed to down-regulation of some cytokines and antibody responses to oral rotavirus vaccine.

Astragalus polysaccharide enhances maternal mucosal immunity against PEDV.

This study highlights the limitations of current porcine epidemic diarrhea virus (PEDV) vaccines in inducing sufficient maternal milk IgA, which is crucial for protecting neonatal piglets. By supplementing Astragalus polysaccharide (APS) into the vaccination regimen, we demonstrated a significant enhancement in milk PEDV-specific IgA levels, as well as improved cellular immune responses. APS also bolstered intestinal immune function and homeostasis in piglets. These findings suggest that APS supplementation could serve as an immune booster to enhance maternal immunity, offering a promising approach to better protect piglets against PEDV.

Anti-Porphyromonas gingivalis Antibody Levels in Patients With Stroke and Atrial Fibrillation: A Systematic Review and Meta-Analysis.

Atrial fibrillation (AF) and stroke are two highly related conditions, with periodontitis and periodontal pathogens, such as Porphyromonas gingivalis (Pg), appearing to be the most prominent common risk factors. In this study, we evaluated studies assessing Pg infection via serum/plasma anti-Pg antibodies in patients with AF and/or stroke. Online databases (PubMed, Scopus, Embase, and the Web of Science) were screened for studies showing the association between anti-Pg antibodies with stroke and/or AF. Relevant data were extracted, and a subsequent random-effects meta-analysis was performed to calculate the pooled odds ratio (OR) or standardized mean difference (SMD) and 95% confidence intervals (CIs) for Pg seropositivity or anti-Pg antibody levels in stroke patients compared to controls. Sixteen studies were included in the systematic review. Based on the meta-analysis performed, there was no significant difference in Pg IgA and IgG levels between patients with stroke and controls (IgA: SMD 0.11, 95% CI -0.02 to 0.25, p = 0.1; IgG: SMD -0.12, 95% CI -1.24 to 0.99, p = 0.83). Similarly, no difference was observed between these groups in terms of Pg IgA and IgG seropositivity (IgA: OR 1.63, 95% CI 1.06-2.50, p = 0.026; IgG: OR 2.30, 95% CI 1.39-3.78, p < 0.001). Subsequently, we reviewed the results of six articles investigating serum or plasma IgG antibodies against Pg in patients with AF. Our results revealed a strict association between Pg infection and AF, with AF patients exhibiting either higher anti-Pg antibody levels or a higher prevalence of positive serum Pg antibodies. Our study supports the clinical utility of Pg infection assessment in patients with periodontitis and those with AF and solicits more focused studies to corroborate its use in clinical settings to enhance overall outcomes, reduce the risk of complications like stroke, and help fine-tune personalized therapies.

Supplementation with Chinese herbal preparations protect the gut-liver axis of Hu sheep, promotes gut-liver circulation, regulates intestinal flora and immunity

The gut-liver axis in ruminants can explain nutrient regulation, the gut-liver cycle, and immune function in ruminant biology through the gut microbe-gut metabolite-liver metabolite relationship. to investigate the effects of herbal feed additives on the gut-liver axis of Hu sheep. In this study, a broadly targeted UPLC-MS/MS metabolomics approach and 16s sequencing of gut microorganisms were used to detect, identify and quantify changes in ileal microorganisms, liver metabolites and ileal metabolites following the addition of Chinese herbal preparations. The addition of a 0.5% herbal feed additive increased ileal IgA, IgG and complement C3 levels. The addition of Chinese herbal preparations can increase the abundance of Firmicutes, Actinobacteriota, Bacteroidota, at the portal level of the ileum, increase the metabolism of organic matter and its derivatives, bile acids, amino acids and their metabolites, coenzymes, and vitamins in the liver and ileum, enhance nutrient absorption and waste metabolism, accelerate liver metabolism, promote gut-liver circulation, and improve ileal and liver immunity. This study provides a theoretical basis for understanding the effects of herbal feed additives on the gut-liver axis in ruminants.

Pathophysiology of De Novo Food Allergies After Solid Organ Transplant in Pediatric Patients.

De novo food allergy is a common phenomenon among pediatric solid organ recipients (8.5%-57%) when compared with the general population (0.45%-10%). Other associated disorders include non-IgE-mediated immune reactions and clinical predisposition to asthma and alterations in the oral mucosa. Originally, passive mechanisms (passive transfer of IgE and immune cells) were thought to be responsible for acute, transient cases of food allergies with a previous history of sensitization for a specific allergen in the donor. Recently proposed pathophysiological mechanisms to explain de novo allergies include TH2/B-cell imbalance, regulatory T-cell (Treg) disruption, gastrointestinal immaturity, and altered gastrointestinal permeability. Recent studies also suggest that immunosuppressive drugs, especially tacrolimus, promote naïve T-cell differentiation into TH2 cells, IgE-promoting cytokine production, decreased IL-5 and IL-10 levels, increased IgA levels, and Treg disruption. Such immunological interactions, in conjunction with altered intestinal permeability, intestinal immaturity in children, history of viral infection, and a personal history of allergies or eczema, are thought to explain most clinical cases of pediatric de novo food allergy after solid organ transplantation reported in the literature. A better understanding of the immunological mechanisms underpinning organ donors and recipients may unveil some of the caveats concerning therapeutic management and improve the quality of life of affected individuals.

Koala ocular disease grades are defined by chlamydial load changes and increases in Th2 immune responses

IntroductionThis study employs bulk RNA sequencing, PCR, and ELISA assays to analyze the pathological factors affecting the outcomes of C. pecorum ocular infections in koalas. It investigates the immune responses and gene expression profiles associated with various stages of koala ocular chlamydiosis.MethodsA cohort of 114 koalas from Queensland, Australia were assessed, with 47% displaying clinical signs of ocular disease. Animals were classified into three cohorts: acute active disease (G1), chronic active disease (G2), and chronic inactive disease (G3), along with subclinical Chlamydia pecorum positive (H2) and healthy (H1) cohorts.ResultsAnalysis of clinical, microbiological, humoral immune and cellular immune biomarkers revealed varying chlamydial loads and anti-chlamydial IgG levels across disease grades, with a negative correlation observed between ocular chlamydial load and anti-chlamydial IgG. Koala ocular mucosa gene expression analysis from 27 koalas identified shared expression pathways across disease cohorts, with a significant upregulation of IFNγ expression and tryptophan metabolism in all disease stages.DiscussionThese findings help elucidate immune response dynamics and molecular pathways underlying koala ocular chlamydiosis, providing insights crucial for disease management strategies.

Securing long-term immunity: The possible necessity of supplementary measles vaccination.

The global initiative to eliminate measles, spearheaded by the World Health Organization, has yet to achieve its intended goals. In Turkey, despite robust vaccination strategies, recent increases in measles cases have been attributed to vaccine hesitancy and irregular migration. This study evaluates measles serology within a pediatric population to determine the impact of vaccination regimens on immunity. A retrospective study at Ankara Bilkent City Hospital analyzed serum measles IgG levels in children aged 1-18 years from January 2020 to August 2023. Exclusions were applied for individuals with positive IgM results, incomplete vaccinations, and immunocompromised conditions. Patients were categorized based on their M-M-R®II vaccine status into those having received either one or two doses. Seropositivity was assessed using the ELISA method. Of the 686 children, 30.2% received a single dose, and 69.8% received two doses of the MMR vaccine. Overall, 70.7% exhibited positive IgG levels. No significant differences were found in IgG levels between those who received one dose and those who received two doses. However, a decline in IgG levels was observed with age, particularly notable in adolescents aged 14-18 years. The study reveals seropositivity rates lower than expected, highlighting challenges in achieving WHO targets. This suggests a potential need for booster doses during adolescence to maintain protective antibody levels. The findings emphasize the importance of continued surveillance and research to adapt vaccination strategies effectively and prevent measles outbreaks, particularly considering the decline in antibody levels and diverse vaccination histories across populations.

Hard-to-treat autoimmune hepatitis and primary biliary cholangitis: The dawn of a new era of pharmacological treatment.

Patients with hard-to-treat autoimmune hepatitis (AIH) or primary biliary cholangitis (PBC) are defined a posteriori as those who do not show a sufficient response or are intolerant to pharmacological treatments, thus not achieving biochemical surrogate endpoints that are associated with long-term liver-related-event-free survival. The absence of a recently harmonized definition of 'complete biochemical response within 6 months (CBR≤6M)', which is defined as the normalization of serum transaminase and IgG levels below the upper limit of normal (ULN) at ≤6 months after treatment initiation is regarded as hard-to-treat AIH. The implementation of CBR≤6M, in turn, has been facilitating clinical trials, e.g., between azathioprine and mycophenolate mofetil, to reconsider appropriate first-line steroid sparing agents, leading to a reduction in the number of hard-to-treat AIH cases. Regarding PBC, one of the disseminated definitions of hard-to-treat patients is the absence of POISE criteria, which are evaluated at 12 months with serum alkaline phosphatase and bilirubin levels, after the introduction of ursodeoxycholic acid. Hard-to-treat PBC not meeting the POISE criteria has very recently been the target population for the U.S. FDA-approved second-line drugs, elafibranor and seladelpar. In future pharmacological treatment of AIH and PBC, the primary objective for AIH is likely to focus on lowering the number of hard-to-treat patients with personalized steroid sparing treatment regimens. A challenging goal in PBC treatment is the further optimization of treatment surrogate endpoints, even to the stricter ALP normalization, with which an indication of second- or later-line drugs might be expanded, but could ultimately lengthen patients' long-term survival.

Irradiated whole cell Chlamydia vaccine confers significant protection in a murine genital tract challenge model.

Chlamydia trachomatis infections are the most common bacterial STIs globally and can lead to serious morbidity if untreated. Development of a killed, whole-cell vaccine has been stymied by coincident epitope destruction during inactivation. Here, we present a prototype Chlamydia vaccine composed of elementary bodies (EBs) from the related mouse pathogen, Chlamydia muridarum (Cm). EBs inactivated by gamma rays (Ir-Cm) in the presence of the antioxidant Mn2+-Decapeptide (DEHGTAVMLK) Phosphate (MDP) are protected from epitope damage but not DNA damage. Cm EBs gamma-inactivated with MDP retain their structure and provide significant protection in a murine genital tract infection model. Mice vaccinated with Ir-Cm (+MDP) exhibited elevated levels of Cm-specific IgG and IgA antibodies, reduced bacterial burdens, accelerated clearance, and distinctive cytokine responses compared to unvaccinated controls and animals vaccinated with EBs irradiated without MDP. Preserving EB epitopes with MDP during gamma inactivation offers the potential for a polyvalent, whole-cell vaccine against C. trachomatis.

Understanding American tegumentary leishmaniasis in urban Montes Claros, Brazil: insights from clinical, immunological and therapeutic investigations.

The challenge of American tegumentary leishmaniasis (ATL) continues in Brazil, presenting a persistent public health issue despite initiatives aimed at public outreach, vector control and health education. To gain a deeper understanding of this disease, a study was conducted in an endemic region located in the northern region of the state of Minas Gerais, Brazil. The study monitored 30 resident patients diagnosed with ATL, using serum samples from 6 healthy individuals as controls. The localized cutaneous form of the disease was found to be predominant, with lesions appearing on various parts of the body and the majority of the affected individuals being male. The study found significantly higher levels of IgG anti-α-Gal antibodies in ATL-infected patients compared to healthy individuals. Treatment of 19 patients with meglumine antimoniate resulted in limited improvement in symptoms for most. Nonetheless, the study found that 12 patients who completed treatment with epithelialization of the lesions showed a significant decrease in IgG anti-α-Gal antibodies, indicating potential applications of this antibody in the diagnosis and monitoring of the disease. The study also identified Leishmania species in 7 analysed patients, revealing 6 cases infected by Leishmania braziliensis and 1 by L. infantum, with a significant difference in the anti-α-Gal responses. The findings of the study emphasize the urgent need for the development of human vaccines and innovative treatment strategies adapted to the diversity of Leishmania species causing cutaneous leishmaniasis and individual patient responses to improve the clinical management of ATL in Brazil and similar endemic regions.

Oral Administration of Zinc Sulfate with Intramuscular Foot-and-Mouth Disease Vaccine Enhances Mucosal and Systemic Immunity

Background/Objectives: Foot-and-mouth disease (FMD) remains a significant global threat to livestock farming. Current commercial FMD vaccines present several challenges, including the risk of infection and adverse injection site reactions due to oil-based adjuvants. The complex immune environment of the gut-associated lymphoid tissue has the potential to induce broad and diverse immune responses. Therefore, we aimed to explore the potential of zinc sulfate as an oral adjuvant to enhance intestinal mucosal immunity and complement the effects of intramuscular (IM) FMD vaccination. Methods: We conducted serological analyses on mice and pigs, measuring secretory IgA (sIgA) levels and evaluating the expression of mucosal immunity-related genes in pigs. These assessments were used to investigate the systemic and mucosal immune responses induced by oral zinc sulfate administration in combination with an IM FMD vaccine. Results: This combination strategy significantly increased structural protein antibody titers and virus neutralization titers in experimental animals (mice) and target animals (pigs) across early, mid-, and long-term periods. Additionally, this approach enhanced the expression of key cytokines associated with mucosal immunity and increased sIgA levels, which are critical markers of mucosal immunity. Conclusions: Oral zinc sulfate administration may synergize with inactivated FMD vaccines, leading to sustained and enhanced long-term immune responses. This novel strategy could reduce the frequency of required vaccinations or allow for a lower antigen dose in vaccines, effectively stimulating the mucosal immune system and boosting systemic immunity. This approach has the potential to improve the overall efficacy of commercial FMD vaccines.

Seroprevalence of anti-SARS-CoV-2 IgM and IgG and COVID-19 vaccine uptake in healthy volunteers in Nairobi, Kenya: a cross-sectional study

IntroductionSeroprevalence of anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) antibodies in the postvaccination period in Kenya remains to be elucidated. This study aimed to determine the seroprevalence of anti-SARS-CoV-2 IgM and IgG and evaluate Covid-19 vaccination uptake in a university setting in Nairobi.MethodsThis cross-sectional study assayed serum anti-SARS-CoV-2 IgM and IgG levels using enzyme-linked immunosorbent assays. A structured questionnaire was used to determine vaccine uptake, vaccine hesitancy and reasons for hesitancy.ResultsA total of 189 participants were enrolled (median age, 21 years; female, 50.8%). The seroprevalence of anti-SARS-CoV-2 was 12.7% for IgM and 87.8% for IgG. Anti-SARS-CoV-2 IgG titers were higher among the vaccinated vs. non-vaccinated individuals (p &amp;lt; 0.001, U = 2817.5), females vs. males (p = 0.024, U = 3616), and those vaccinated ≤ 6 months before the study vs. those vaccinated &amp;gt;1 year earlier (p = 0.002, H = 12.359). The vaccination hesitancy rate was 43.4% and the underlying reasons included mistrust (22.4%), health concerns (19.7%), and lack of information (18.4%).DiscussionThe high seroprevalence of anti-SARS-CoV-2 IgG is an indication of high exposure to SARS-CoV-2 either through natural infection or through vaccination. The high vaccine hesitancy noted necessitates community engagement, and public education to dispel myths and misinformation prior to roll out of new vaccines and other health interventions.

Clinical and immunological features of four patients with activation-induced cytidine deaminase deficiency: Renal amyloidosis and other presentations.

Activation-induced cytidine deaminase (AID) deficiency is a rare autosomal recessive inborn error of immunity (IEI) characterized by increased susceptibility to infections, autoimmunity, and/or autoinflammation. AID plays an important role in immunoglobulin class switching and somatic hypermutation. AID deficiency patients have very low or absent levels of IgG, IgA, and IgE, while IgM level is elevated. The disease is designated as type 2 hyperimmunoglobulin M syndrome (HIGM-2). To date, around 130 patients with HIGM-2 have been reported, none from Egypt. Four patients from three different consanguineous families with elevated serum IgM and low IgG and IgA were included in the study. After the exclusion of CD40 and/or CD40L deficiency by flow cytometry, patients' samples were tested by a panel covering 452 genes (four bases PID-Pro) on the Illumina Miseq platform. All patients suffered repeated infections since childhood. Patients 1-3 had inflammatory bowel disease-like (IBD-like) symptoms, while patient 4 did not have autoimmune manifestations. Patient 1 is the first HIGM-2 patient to be reported to have renal amyloidosis as part of the autoinflammation. Patients 1-3 had the same pathogenic variant (NM_020661.4 (AID):c.406del, p.Ile136Ter), while patient 4 had another pathogenic variant (NM_020661.4 (AID):c.374G>A, p.Gly125Glu). The variant p.Ile136Ter was not reported before in any of the documented HIGM-2 patients. HIGM-2 is a rare IEI that can be overlooked; hence, patients' diagnosis is delayed. Autoimmune and autoinflammatory manifestations develop later in the disease course leading to significant morbidities. The diagnosis can be suspected after exclusion of CD40/CD40L deficiencies by flow cytometry, and the diagnosis can be confirmed by genetic testing.

Effects of different doses of rituximab on immunoglobulin levels in high-risk pediatrics with Burkitt's lymphoma.

Studies have confirmed that rituximab (RTX) can improve the efficacy of BL, but there is a certain effect on the level of immunoglobulin, which will lead to the verification of infection, and the previous study of our center has confirmed that reducing the dose of RTX (4 doses) can achieve a similar effect to the standard dose of RTX (6 doses), can it reduce the effect on the level of immunoglobulin? To date, few studies have concentrated on the effects of immunoglobulin (Ig) on Chinese paediatric patients. This study aimed to examine whether there is a variation in the impact of different doses of RTX on immunoglobulin levels in the high-risk group of children with BL. Clinical data of high-risk pediatric patients with BL who were treated in Beijing Children's Hospital (Beijing, China) were retrospectively analysed. Baseline characteristics and serum Ig levels were collected at four distinct time points (t0 = pre-chemotherapy, t1 = at the end of chemotherapy, t2 = 6 months post-chemotherapy, t3 = 12 months post-chemotherapy). Ig levels were measured at various time points before and after treatment within three RTX treatment groups: R0 group (standard chemotherapy without RTX), R6 group (6 doses of RTX + chemotherapy), and R4 group (4 doses of RTX + chemotherapy). The objective was to compare whether differences existed among the three groups. The results revealed that the study enrolled 300 high-risk BL patients, including 256 boys and 44 girls, distributed across three groups based on RTX dosage: R0 group (n = 38), R6 group (n = 87), and R4 group (n = 175). Median Ig levels were assessed at four time points (t0, t1, t2, t3) for each group. In the R0 group, IgA and IgM levels significantly decreased at t1 compared with t0 (P = 0.006 and 0.002, respectively), while were gradually recovered at t2, returning to t0 levels at t3 (P = 0.073 and 0.293, respectively). IgG levels exhibited no significant difference between t0 and t1 (P = 0.89), reaching their lowest levels at t2 and returning to t0 levels at t3 (P = 0.14). In the R4 group, the minimum levels of IgA, IgM, and IgG were identified at t1 (P < 0.001, < 0.001, and < 0.001, respectively), which were gradually recovered at t2, while remained lower than t0 levels at t3 (P < 0.001, < 0.001, and = 0.005, respectively). The R6 group exhibited reduction in IgA and IgM levels at t1, with gradual recovery at t2 and t3, while remained lower than t0 levels (P = 0.003 and < 0.001, respectively). IgG levels in the R6 group decreased at t1 (P < 0.001) and did not return to t0 levels at t3 (P = 0.004). In the R4 and R6 groups, it was observed that children with hypogammaglobulinemia pre-RTX were more likely to combine with persistent hypogammaglobulinemia (PH-Ig) post-RTX. A 1:1 matched comparison between R4 and R6 groups (78 patients each) revealed consistently higher IgA, IgM, and IgG levels in the R4 group at each time point after chemotherapy. Notably, IgA and IgG levels recovered earlier in the R4 group than those in the R6 group (P < 0.05). Burkitt lymphoma in the high-risk group were more likely to complicated hypoimmunoglobulinemia after treatment, it is important to monitor Ig levels before and during treatment, and to inform replacement therapy for Ig. Compared with standard chemotherapy group, the RTX group had a longer time of low Ig and a slower recovery, reducing the dosage of rituximab can improve the recovery of IgA and IgG levels.

Avidity maturation of anti-spike IgG after vaccination in COVID-19 convalescent vs COVID-19 naïve patients.

Antibodies and avidity maturation contribute to long-lasting immunity, and previous COVID-19 seems to enhance the immune response after vaccination. The aim of this study was to compare the immune response after vaccination between COVID-19 convalescents and naïve patients. Blood samples from COVID-19 convalescents and naïve patients, taken 1, 3 and 6 months after the second dose of vaccine (mRNA-vaccine BNT162b2), were analysed for anti-spike IgG and avidity. Questionnaires concerning side effects were used. Thirty-one patients in the COVID-19 cohort and 30 patients in the naïve cohort were included. High levels of anti-spike IgG and avidity index were seen. Anti-spike IgG were significantly higher in the COVID-19 cohort and declining (median 1250, 566, 282 RU/ml vs 565, 187, 65 RU/ml). Avidity did not change over time (median at 6 months 78% vs 65%). The most common side effects were pain at the injection site, malaise and headache. In conclusion, high levels of anti-spike IgG after vaccination were seen and most patients developed high-avidity antibodies, although antibody levels and avidity were higher in the COVID-19 cohort. Over time, the levels of anti-spike IgG declined, yet avidity remained high. Side effects did not differ between groups and were of short duration.

Modified PEG-Lipids Enhance the Nasal Mucosal Immune Capacity of Lipid Nanoparticle mRNA Vaccines

Background/Objectives: Omicron, the predominant variant of SARS-CoV-2, exhibits strong immune-evasive properties, leading to the reduced efficacy of existing vaccines. Consequently, the development of versatile vaccines is imperative. Intranasal mRNA vaccines offer convenient administration and have the potential to enhance mucosal immunity. However, delivering vaccines via the nasal mucosa requires overcoming complex physiological barriers. The aim of this study is to modify PEGylated lipids to enhance the mucosal immune efficacy of the vaccine. Methods: The PEGylated lipid component of lipid nanoparticle (LNP) delivery vectors was modified with chitosan or mannose to generate novel LNPs that enhance vaccine adhesion or targeting on mucosal surfaces. The impact of the mRNA encoding the receptor-binding domain of Omicron BA.4/BA.5 on the immune response was examined. Results: Compared to the unmodified LNP group, the IgG and IgA titers in the chitosan or mannose-modified LNP groups showed an increasing trend. The chitosan-modified group showed better effects. Notably, the PEGylated lipid with 1.5 mol% of chitosan modification produced high levels of IgG1 and IgG2a antibodies, promoting Th1/Th2 responses while also generating high levels of IgA, which can induce stronger cellular immunity, humoral immunity, and mucosal immunity. Conclusions: The 1.5 mol% of chitosan-modified LNPs (mRNA-LNP-1.5CS) can serve as a safe and effective carrier for intranasal mRNA vaccines, offering a promising strategy for combating the Omicron variant.

A Comparative Study of Direct Immunofluorescence Patterns in Linear IgA Bullous Dermatosis Versus Dermatitis Herpetiformis

Background: Dermatitis herpetiformis (DH) is typically characterized by granular IgA deposition in the papillary dermis on direct immunofluorescence (DIF), and linear IgA bullous dermatosis (LABD) is characterized by linear deposition of IgA along the basement membrane. Other DIF findings in both conditions may include IgG, IgM, and C3 deposition in various patterns. In cases where immunofluorescence findings are unclear, such as continuous but somewhat granular IgA deposition along the dermal–epidermal junction, additional DIF patterns may be helpful in the diagnostic process. Methods: Forty-five cases of digitized images of LABD and 48 digitized images of DH cases were analyzed. The data regarding the positivity and patterns of immunoglobulins were documented and analyzed. Results: None of the LABD cases had a picket fence pattern, while 47.9% (n = 23) of the DH cases had the pattern. Elevated levels of IgG and IgM were found in LABD compared with DH. In DH, higher IgM and kappa light chain levels were observed in the deposited particles compared with those in LABD. Conclusions: The “picket fence pattern” is highly specific for DH (Specificity 100%) but less sensitive (Sensitivity 47.9%). It may be helpful to differentiate between DH and LABD for a more accurate diagnosis.

Clinical applications of immunoglobulin G against different individual Aspergillus species for the diagnosis of chronic pulmonary aspergillosis among at-risk populations

ABSTRACT Aspergillus fumigatus-specific IgG is often used as a diagnostic test for chronic pulmonary aspergillosis (CPA), but few studies have evaluated the performance and serology of IgGs from species other than A. fumigatus. In this study, we evaluated the serology and performance of different Aspergillus species-specific IgG antibodies in patients with CPA and at-risk populations and whether different Aspergillus species-specific IgGs could be of clinical utility and aid in the diagnosis of CPA caused by all Aspergillus species. A total of 187 participants were included between 2020 and 2022 (12 with CPA, 75 with old tuberculosis [TB], 45 with active TB and 55 with bronchiectasis). We measured the serum Aspergillus fumigatus, flavus, terreus, niger-specific, and mixed Aspergillus IgG levels (Phadia ImmunoCap). The correlation was the strongest between A. fumigatus and A. niger (Spearman’s rank: 0.940), followed by A. niger and A. flavus (Spearman’s rank: 0.915). A. terreus-specific IgG was less strongly correlated with the other three Aspergillus species-specific IgG (Spearman’s rank: 0.828–0.849). A. flavus (4 of 6, 67%) was the dominant species. Using the at-least-one-positive approach, the highest performance was obtained when A. fumigatus and A. flavus IgGs were used (sensitivity, 0.75; specificity, 0.84). Significant cross-reactivity exists among different Aspergillus-species IgGs although the correlation may be less significant for A. terreus. In addition to the commonly used A. fumigatus IgG test, IgGs specific to local prevalent Aspergillus species may provide additional clinical utility.