Low Titers Research Articles

Clinical characteristics and therapeutic effect of myasthenia gravis coexisting with thyroid eye disease.

Here, we describe the clinical characteristics and therapeutic effects of myasthenia gravis (MG) coexisting with thyroid eye disease (TED). We collated clinical data from MG patients in our hospital between 2012 and 2022 and analyzed the clinical characteristics of MG patients with hyperthyroidism, MG patients with TED and ocular myasthenia gravis (OMG) patients with TED. We recruited 62 MG patients with hyperthyroidism, including 13 MG patients with TED and 10 OMG patients with TED. There were 70 MG patients without hyperthyroidism; 29 of these were OMG. Compared with patients without hyperthyroidism, patients with hyperthyroidism had an earlier age at onset and milder clinical symptoms (P < 0.05). The incidence of thymus hyperplasia in patients with hyperthyroidism and TED was significantly lower than that in patients without TED (38.5% vs. 69.4%, P < 0.05); these patients also had a significantly lower antibody titer for the acetylcholine receptor [0.72 (0.27, 14.93) nmol/L vs. 2.38 (0.28, 49.51) nmol/L, P < 0.05]. Diplopia was significantly more frequent in OMG patients with TED than in patients with OMG (84.6% vs. 44.8%, P < 0.05), and the rate of diplopia in OMG patients with TED was significantly higher after treatment with bromostigmine and glucocorticoid (69.2% vs. 3.4%, P < 0.05). MG patients with TED had a significantly lower incidence of thymus hyperplasia and a lower antibody titer for the acetylcholine receptor. Patients with OMG and TED are more likely to develop diplopia; it is very difficult to treat diplopia in these patients.

Clinical immunological characteristics of anti-interferon-γ autoantibodies syndrome: a 3 year prospective cohort study

ABSTRACT Anti-interferon-γ autoantibodies (AIGAs) syndrome is susceptible to disseminated opportunistic infections due to increased AIGAs, but its clinical immunological characteristics remain unrecognized. We conducted a prospective cohort study between January 2021 and December 2023, recruiting patients with opportunistic infections who were categorized into AIGAs-positive and AIGAs-negative groups. Clinical immunological data and outcomes were documented. A subset of AIGAs-positive patients received glucocorticoid treatment, and its effectiveness was evaluated. A total of 238 patients were enrolled, with 135 AIGAs-positive and 103 AIGAs-negative patients. AIGAs-positive patients showed higher rates of multiple pathogen dissemination, shorter progression-free survival (PFS), and increased exacerbation frequency. They also showed elevated erythrocyte sedimentation rate (ESR), globulin (GLB), immunoglobulin (Ig)G, IgE, and IgG4 levels. Among the 70 AIGAs-positive patients monitored for at least six months, three subtypes were identified: high AIGAs titer with immune damage, high AIGAs titer without immune damage, and low AIGAs titer without immune damage. Of the 55 patients followed for 1 year, decreasing AIGAs titer and immune indices (GLB, IgG, IgE, IgG4) were observed. Among the 31 patients with high AIGAs titer and immune damage treated with low-dose glucocorticoids at the stable phase, reductions were observed in immune indices and AIGAs titer in 67.74% of cases. In summary, AIGAs-positive patients exhibit infectious and immunological characteristics. Elevated AIGAs, IgG, IgG4, and IgE indicate abnormal immune damages. AIGAs titer generally decrease over time. Stable-phase AIGAs-positive patients can be categorized into three subtypes, with those having high AIGAs titer and increased immune indices potentially benefitting from glucocorticoid treatment.

Maternal Helminth Infection Causes Dysfunctional B Cell Development in Male Offspring.

Infections during pregnancy are known to trigger alterations in offspring immunity, often leading to increased disease susceptibility. Maternal helminth infections correlate with lower Ab titers to certain childhood immunizations and putative decreased vaccine efficacy. The mechanisms that underlie how maternal infection blunts offspring humoral responses are unclear. Using our murine model of maternal schistosomiasis, we found that maternal helminth infection decreases the germinal center response of all offspring to tetanus immunization. However, only male offspring have defects in memory B cell and long-lived plasma cell generation. We found this sex-specific aberration begins during B cell development within the bone marrow via alteration of the IL-7 niche and persists throughout antigenic activation in the germinal center in the periphery. Critically, these defects in males are cell intrinsic, persisting following adoptive transfer to control male pups. Together, these data show that maternal infections can alter both the bone marrow microenvironment and the development of B lymphocytes in a sex-specific manner. This study correlates maternal infection induced defects in early life B cell development with ineffective Ab responses after vaccination.

Delayed peak antibody titers after the second dose of SARS-CoV-2 vaccine in solid organ transplant recipients: Prospective cohort study

Poor post-vaccination production of antibody against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a concern among solid organ transplant (SOT) recipients. Furthermore, the timing and kinetics of antibody titers after the second vaccine dose are unknown. We conducted a multicenter prospective observational study that included 614 SOT recipients: 460 kidney, 53 heart, 50 liver, 20 lung, and 31 simultaneous pancreas–kidney (SPK). The participants received two doses of the mRNA vaccine (Pfizer BNT162b2 or Moderna mRNA-1273), as indicated. Serum samples were collected before the first and second vaccinations and at 1, 3, and 6 months after the second vaccine dose, which were then assessed for SARS-CoV-2 antibodies. The overall seropositivity rate was 43% at 1 month after administration of the second vaccine dose; it gradually increased to 68% at 3 months after second dose administration and to 70% at 6 months. In addition, recipient of kidney, lung or SPK transplants had lower antibody titers at the 3- and 6-month time points than did the other recipients. SOT recipients acquired SARS-CoV-2 S-IgG antibodies slowly, and the peak titer differed significantly from that of the general population.

Risk factors of HBV reactivation in leukemia patients with resolved HBV infection after allogeneic hematopoietic stem cell transplantation

BackgroundThe hepatitis B surface antigen (HBsAg)–negative and antibody to hepatitis B core antigen (anti-HBc)–positive patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are at risk of HBV reactivation (HBVr). MethodsTo analyze the risk factors for HBVr, a total of 1,042 leukemia patients(≥18years of age), who underwent allo-HSCT from January 2016 to April 2022 in The First Affiliated Hospital of Soochow University, were enrolled in the study. Finally, 193 leukemia patients with resolved HBV infection were included into the study. ResultsHBVr occurred in 22 patients (11.39 %), and the median time to HBVr was 24 months (with a range of 11-51months). Hepatitis flares developed in 22.73 % of patients with HBVr, and hepatic failure occurred in 1 patient. During the follow-up period, only 1(1.3 %) patient experienced HBVr among 79 patients with antiviral prophylaxis. While 21(18.42 %) patients experienced HBVr among 114 patients without antiviral prophylaxis. The cumulative incidence of HBV reactivation at 3 years was 44.4. % for anti-HBs-negative donors/recipients with a low anti-HBs titer (<100IU/L) and 7.1 % for anti-HBs-positive donors/recipients with a high anti-HBs titer (≥100IU/L) respectively. In addition, univariate and multivariate Cox regression analyses confirmed the use of rituximab as a risk factor for HBV reactivation. ConclusionThe univariate and multivariate analyses confirmed that the anti-HBs titer in both recipients and donors are protective indicators to prevent incidence of HBVr. In addition, antiviral prophylaxis can significantly reduce the incidence of HBVr.

Evolution of SARS-CoV-2 in the murine central nervous system drives viral diversification.

Severe coronavirus disease 2019 and post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are associated with neurological complications that may be linked to direct infection of the central nervous system (CNS), but the selective pressures ruling neuroinvasion are poorly defined. Here we assessed SARS-CoV-2 evolution in the lung versus CNS of infected mice. Higher levels of viral divergence were observed in the CNS than the lung after intranasal challenge with a high frequency of mutations in the spike furin cleavage site (FCS). Deletion of the FCS significantly attenuated virulence after intranasal challenge, with lower viral titres and decreased morbidity compared with the wild-type virus. Intracranial inoculation of the FCS-deleted virus, however, was sufficient to restore virulence. After intracranial inoculation, both viruses established infection in the lung, but dissemination from the CNS to the lung required the intact FCS. Cumulatively, these data suggest a critical role for the FCS in determining SARS-CoV-2 tropism and compartmentalization.

CHALLENGE IN TREATING OPTIC NEURITIS IN PATIENT WITH CEREBRAL TOXOPLASMOSIS RELATED TO IMMUNOCOMPROMISED CONDITION

Introduction: This study aimed to discuss the prognosis of optic neuritis in a patient with cerebral toxoplasmosis related to an immunocompromised condition. Case Report: A 28-year-old female complained of blurred vision and double vision 2 weeks before admission, accompanied by headache, low extremities weakness, dysphonia, and dysphagia. Visual acuity of both eyes was 6/30 and worsened to 6/60 in a couple of days. Anterior segment examination revealed anisocoria pupil, and RAPD was positive in the left eye. Funduscopic examination showed a blurry margin and hyperemia of the optic nerve head. There was impaired eye movement, indicating oculomotor and abducens nerve palsies. High titer of IgG Antibody Toxoplasma (264) and very low titer of CD4 (&lt;50) with non-reactive HIV rapid test were found in laboratory findings. Multiple ring enhancement was shown in MRI finding. Unfortunately, patient passed away during hospitalization due to respiratory failure. Discussion: Toxoplasmosis-associated optic neuritis is rare and usually becomes potentially serious. Although parasite detection by microscopy and bioassay is considered the gold standard for the diagnosis of toxoplasmosis, clinical diagnosis relies more on serological examination methods. The high proportion of deaths from this disease is mostly caused by late diagnosis of the infection. Conclusion: Optic neuritis that accompanied by systemic disorders needs special attention and comprehensive treatment among multidisciplinary divisions, especially in the immunocompromised condition. Early detection and primary prevention are important to improve prognosis and survival rate.

A Rationally Designed H5 Hemagglutinin Subunit Vaccine Provides Broad-Spectrum Protection against Various H5Nx Highly Pathogenic Avian Influenza Viruses in Chickens.

The evolution of the H5 highly pathogenic avian influenza (HPAI) viruses has led to the emergence of distinct groups with genetically similar clusters of hemagglutinin (HA) sequences. In this study, a consensus H5 HA sequence was cloned into the baculovirus expression system. The HA protein was expressed in baculovirus-infected insect cells and utilized as the antigen for the production of an oil emulsion-based H5 avian influenza vaccine (rBacH5Con5Mut). Twenty-one-day-old SPF chickens were immunized with this vaccine and then challenged at 21 days post-vaccination with clade 2.3.2.1, clade 2.3.4.4, and clade 7.2 of H5 HPAI viruses. The sera of vaccinated chickens exhibited high hemagglutination inhibition (HI) titers against the rBacH5 vaccine antigen, while lower HI titers were observed against the different challenge virus H5 hemagglutinins. Furthermore, the rBacH5Con5Mut vaccine provided 100% protection from mortality and clinical signs. Virus isolation results showed that oropharyngeal and cloacal shedding was prevented in 100% of the vaccinated chickens when challenged with clade 2.3.2.1 and clade 2.3.4.4 H5 viruses. When the rBacH5Con5Mut vaccine candidate was administrated at one day of age, 100% protection was demonstrated against the challenge of clade 2.3.4.4 virus at three weeks of age, indicating the potential of this vaccine for hatchery vaccination. Overall, A single immunization of rBacH5Con5Mut vaccine candidate with a consensus HA antigen can protect chickens against different clades of H5 HPAI viruses throughout the rearing period of broiler chickens without a boost, thus fulfilling the criteria for an efficacious broad-spectrum H5 avian influenza vaccine.

Effect of metabolic dysfunction-associated steatotic liver disease on BNT162b2 immunogenicity against the severe acute respiratory syndrome coronavirus 2 omicron variant.

We aimed to investigate the effect of metabolic dysfunction-associated steatotic liver disease (MASLD) on three-dose BNT162b2 immunogenicity to the omicron variant. Adult recipients of three doses of BNT162b2 were prospectively recruited between May and December 2021. The serology of the neutralizing antibody by live virus microneutralization (vMN) to the omicron variant was measured at baseline, day 180, and day 360 after the first dose. The primary outcome was seroconversion (vMN titer≥10) at day 360. Exposure of interest was MASLD, defined as hepatic steatosis (controlled attenuation parameter≥248dB/m on transient elastography) plus at least one of five cardiometabolic risk factors. Subjects with prior COVID-19 were excluded. A multivariable logistic regression model was used to derive the adjusted odds ratio of seroconversion with MASLD by adjusting for age, sex, antibiotic use, and proton pump inhibitor use. One hundred forty-eight BNT162b2 recipients (male: 48 [32.4%]; median age: 51.0years [interquartile range, IQR: 44.5-57.3]) were recruited. The median time from the first dose to the third dose was 8.5months (IQR: 7.9-8.9). MASLD subjects had a lower seroconversion rate than non-MASLD ones (89.6% vs 99.0%; P=0.007). MASLD was the only independent risk factor for seroconversion (adjusted odds ratio: 0.051, 95% confidence interval: 0.002-0.440). Subgroup analysis of immunogenicity at 4months after the third dose shows significantly lower vMN titer (13.06 [IQR: 7.69-22.20] vs 33.49 [IQR: 24.05-46.53]; P=0.004) and seroconversion rate (76.9% vs 97.4%; P=0.016) in MASLD than non-MASLD subjects, but not within 4months from the third dose (vMN titer: 46.87 [IQR: 33.12-66.02] vs 41.86 [IQR: 34.47-50.91], P=0.240; seroconversion rate: 94.3% vs 100%, P=0.131). Metabolic dysfunction-associated steatotic liver disease was a risk factor for poorer immunogenicity to the omicron variant, with a more pronounced waning effect compared among three-dose BNT162b2 recipients.

Impact of Baseline Anti-ABO Antibody Titer on Biliary Complications in ABO-Incompatible Living-Donor Liver Transplantation.

Background: Although advancements in desensitization protocols have led to increased ABO-incompatible (ABOi) living-donor liver transplantation (LDLT), a higher biliary complication rate remains a problem. This study evaluated the effect of baseline anti-ABO antibody titers before desensitization on biliary complications after ABOi LDLT. Methods: The study cohort comprised 116 patients in the ABO-compatible group (ABOc), 29 in the ABOi with the low titer (<1:128) group (ABOi-L), and 14 in the high titer (≥1:128) group (ABOi-H). Results: Biliary complications occurred more frequently in the ABOi-H group than in the ABOi-L and ABOc groups (7 [50.0%] vs. 8 [27.6%] and 24 [20.7%], respectively, p = 0.041). Biliary complication-free survival was significantly worse in the ABOi-H group than in the other groups (p = 0.043). Diffuse intrahepatic biliary strictures occurred more frequently in the ABOi-H group than in the other groups (p = 0.005). Multivariable analysis revealed that the high anti-ABO antibody titer (≥1:128) is an independent risk factor for biliary complications (hazard ratio 3.943 [1.635-9.506]; p = 0.002). Conclusions: A high baseline anti-ABO antibody titer (≥1:128), female sex, and hepatic artery complications are significant risk factors for biliary complications.

An analysis of the effect of low titer O whole blood (LTOWB) proportions for resuscitation after trauma on 6-hour and 24-hour survival

IntroductionHemorrhage is a leading cause of death. Blood products are used for the treatment of hemorrhagic shock. The use of low titer group O whole blood (LTOWB) has become more common. MethodsData from patients ≥15 years of age in the Trauma Quality Improvement Program (TQIP) database that received ≥10 units of packed red cells and/or LTOWB within the first 4-h of hospital arrival were included. The proportion of LTWOB of total blood products administered was correlated to 6- and 24-h mortality. Results12,763 met inclusion, 3827 (30 %) received LTOWB. On multivariable logistic regression (MVLR), there was no difference in survival at 6 h with a LTOWB. When assessing 24-h survival, there was improved survival with LTOWB ≥10 % (OR 1.18, 1.08–1.28). ConclusionsIn this analysis of TQIP data, patients receiving ≥10 units of PRBC or LTOWB, we found that higher proportions of LTOWB transfusion relative to the total volume of blood products transfused during the first 4 h were associated with improved 24-h, but not 6-h survival.

The Pathogenic Role of Anti-Granulocyte-Macrophage Colony-Stimulating Factor Autoantibodies in the Nocardiosis with the Central Nervous System Involvement.

Anti-granulocyte-macrophage colony-stimulating factor autoantibodies (anti-GM-CSF Abs) are implicated in the pathogenesis of Cryptococcus gattii (C. gattii) infection and pulmonary alveolar proteinosis (PAP). Their presence has also been noted in nocardiosis cases, particularly those with disseminated disease. This study delineates a case series characterizing clinical features and specificity of anti-GM-CSF Abs in nocardiosis patients. In this study, eight patients were recruited to determine the presence or absence of anti-GM-CSF Abs. In addition to the detailed description of the clinical course, we thoroughly investigated the autoantibodies regarding the characteristics, isotypes, subclasses, titers, and neutralizing capacities by utilizing the plasma samples from patients. Of eight patients, five tested positive for anti-GM-CSF Abs, all with central nervous system (CNS) involvement; patients negative for these antibodies did not develop CNS nocardiosis. Distinct from previously documented cases, none of our patients with anti-GM-CSF Abs exhibited PAP symptoms. The titer and neutralizing activity of anti-GM-CSF Abs in our cohort did not significantly deviate from those found in C. gattii cryptococcosis and PAP patients. Uniquely, one individual (Patient 3) showed a minimal titer and neutralizing action of anti-GM-CSF Abs, with no relation to disease severity. Moreover, IgM autoantibodies were notably present in all CNS nocardiosis cases investigated. The presence of anti-GM-CSF Abs suggests an intrinsic immunodeficiency predisposing individuals toward CNS nocardiosis. The presence of anti-GM-CSF Abs helps to elucidate vulnerability to CNS nocardiosis, even with low titer of autoantibodies. Consequently, systematic screening for anti-GM-CSF Abs should be considered a crucial diagnostic step for nocardiosis patients.

Identification of type 1 diabetes risk phenotypes using an outcome-guided clustering analysis.

Although statistical models for predicting type 1 diabetes risk have been developed, approaches that reveal the heterogeneity of the at-risk population by identifying clinically meaningful clusters are lacking. We aimed to identify and characterise clusters of islet autoantibody-positive individuals who share similar characteristics and type 1 diabetes risk. We tested a novel outcome-guided clustering method in initially non-diabetic autoantibody-positive relatives of individuals with type 1 diabetes, using the TrialNet Pathway to Prevention study data (n=1123). The outcome of the analysis was the time to development of type 1 diabetes, and variables in the model included demographic characteristics, genetics, metabolic factors and islet autoantibodies. An independent dataset (the Diabetes Prevention Trial of Type 1 Diabetes Study) (n=706) was used for validation. The analysis revealed six clusters with varying type 1 diabetes risks, categorised into three groups based on the hierarchy of clusters. Group A comprised one cluster with high glucose levels (median for glucose mean AUC 9.48 mmol/l; IQR 9.16-10.02) and high risk (2-year diabetes-free survival probability 0.42; 95% CI 0.34, 0.51). Group B comprised one cluster with high IA-2A titres (median 287 DK units/ml; IQR 250-319) and elevated autoantibody titres (2-year diabetes-free survival probability 0.73; 95% CI 0.67, 0.80). Group C comprised four lower-risk clusters with lower autoantibody titres and glucose levels (with 2-year diabetes-free survival probability ranging from 0.84-0.99 in the four clusters). Within group C, the clusters exhibit variations in characteristics such as glucose levels, C-peptide levels and age. A decision rule for assigning individuals to clusters was developed. Use of the validation dataset confirmed that the clusters can identify individuals with similar characteristics. Demographic, metabolic, immunological and genetic markers may be used to identify clusters of distinctive characteristics and different risks of progression to type 1 diabetes among autoantibody-positive individuals with a family history of type 1 diabetes. The results also revealed the heterogeneity in the population and complex interactions between variables.

Antibacterial Activity of Ethanol Extract from Australian Finger Lime.

Australian finger lime (Citrus australasica L.) has become increasingly popular due to its potent antioxidant capacity and health-promoting benefits. This study aimed to determine the chemical composition, antibacterial characteristics, and mechanism of finger lime extract. The finger lime extracts were obtained from the fruit of the Australian finger lime by the ethanol extraction method. The antibacterial activity of the extract was examined by detecting the minimum inhibitory concentration (MIC) for two Gram-positive and four Gram-negative bacterial strains in vitro, as well as by assessing variations in the number of bacteria for Candidatus Liberibacter asiaticus (CLas) in vivo. GC-MS analysis was used to identify the antibacterial compounds of the extract. The antibacterial mechanisms were investigated by assessing cell permeability and membrane integrity, and the bacterial morphology was examined using scanning electron microscopy. The extract demonstrated significant antibacterial activity against Staphylococcus aureus, Bacillus subtilis, and Gram-negative bacterial species, such as Escherichia coli, Agrobacterium tumefaciens, Xanthomonas campestris, Xanthomonas citri, and CLas. Among the six strains evaluated in vitro, B. subtilis showed the highest susceptibility to the antimicrobial effects of finger lime extract. The minimum inhibitory concentration (MIC) of the extract against the tested microorganisms varied between 500 and 1000 μg/mL. In addition, the extract was proven effective in suppressing CLas in vivo, as indicated by the lower CLas titers in the treated leaves compared to the control. A total of 360 compounds, including carbohydrates (31.159%), organic acid (30.909%), alcohols (13.380%), polyphenols (5.660%), esters (3.796%), and alkaloids (0.612%), were identified in the extract. We predicted that the primary bioactive compounds responsible for the antibacterial effects of the extract were quinic acid and other polyphenols, as well as alkaloids. The morphology of the tested microbes was altered and damaged, leading to lysis of the cell wall, cell content leakage, and cell death. Based on the results, ethanol extracts from finger lime may be a fitting substitute for synthetic bactericides in food and plant protection.

Abstract Tu008: Efficient Intramyocardial Delivery of EV-Encapsulated AAVs to Target Cardiomyocytes in a Pre-Clinical Swine Model

Background: Adeno-associated viruses (AAV) have been widely used to deliver therapeutic genes to the heart due to their safety and efficacy. However, a major obstacle to their successful gene delivery is the presence of neutralizing antibody (NAb) which form during natural exposure to AAV or following AAV administration. Our recent publication has shown that EV-encapsulated AAVs (EV-AAVs) shields AAVs from NAb neutralization, and overcoming this key roadblock associated with AAV-mediated gene therapy. Hypothesis: In this study, we addressed whether EV-AAVs can target cardiomyocytes in vivo . Aims: To test whether cardiomyocytes effectively uptake EV-AAVs in vivo , in a pre-clinical swine model. Methods and Results: Adult pigs prescreened for a lower NAb titer were randomly assigned to receive intramyocardial administration of either vehicle, AAV6-Luciferase or EV-AAV6-Luciferase. A total of six injections across three injection sites within the left ventricle (LV) were administered per animal. All animals were sacrificed at four weeks and liver and the LV tissues were collected. Luciferase activity assay, flow cytometry analysis of isolated cardiomyocytes (CM) and non-myocytes (NM), and immunofluorescence microscopy were performed to evaluate transgene expression and cellular tropism. Echocardiography was performed at baseline and at 4W to monitor cardiac function. At 4W, EV-AAV6s resulted in a higher luciferase expression in LV compared to nude AAV6 particles. Expression in the LV was higher compared to the liver. Flow cytometry analysis revealed a higher luciferase expression in CM compared to NM, which was corroborated by Immunofluorescence. No differences were detected in the global heart function across groups. Biodistribution of EV-AAV uptake and transgene expression are being studied with intramyocardial and intracoronary delivery mechanisms. Conclusion: EV-AAVs deliver higher amounts of genes than nude AAV6 via intramyocardial administration in a pre-clinical swine model. CMs preferentially uptake EV-AAVs compared to NMs. Our studies suggest that EV-AAVs are a superior cardiac gene delivery vector for future clinical studies.

Stiff Person Syndrome and GAD Antibody-Spectrum Disorders.

Antibodies against glutamic acid decarboxylase (GAD), originally associated with stiff person syndrome (SPS), define the GAD antibody-spectrum disorders that also include cerebellar ataxia, autoimmune epilepsy, limbic encephalitis, progressive encephalomyelitis with rigidity and myoclonus (PERM), and eye movement disorders, all of which are characterized by autoimmune neuronal excitability. This article elaborates on the diagnostic criteria for SPS and SPS spectrum disorders, highlights disease mimics and misdiagnoses, describes the electrophysiologic mechanisms and underlying autoimmunity of stiffness and spasms, and provides a step-by-step therapeutic scheme. Very-high serum GAD antibody titers are diagnostic for GAD antibody-spectrum disorders and also predict the presence of GAD antibodies in the CSF, increased intrathecal synthesis, and reduced CSF γ-aminobutyric acid (GABA) levels. Low serum GAD antibody titers or the absence of antibodies generates diagnostic challenges that require careful distinction in patients with a variety of painful spasms and stiffness, including functional neurologic disorders. Antibodies against glycine receptors, first found in patients with PERM, are seen in 13% to 15% of patients with SPS, whereas amphiphysin and gephyrin antibodies, seen in 5% of patients with SPS spectrum disorders, predict a paraneoplastic association. GAD-IgG from different SPS spectrum disorders recognizes the same dominant GAD intracellular epitope and, although the pathogenicity is unclear, is an excellent diagnostic marker. The biological basis of muscle stiffness and spasms is related to autoimmune neuronal hyperexcitability caused by impaired reciprocal γ-aminobutyric acid-mediated (GABA-ergic) inhibition, which explains the therapeutic response to GABA-enhancing agents and immunotherapies. It is essential to distinguish SPS spectrum disorders from disease mimics to avoid both overdiagnoses and misdiagnoses, considering that SPS is treatable if managed correctly from the outset to prevent disease progression. A step-by-step, combination therapy of GABA-enhancing medications along with immunotherapies ensures prolonged clinical benefits.

Predictors of Functional Cure of Chronic Hepatitis B Virus Infection: A Long-Term Follow-Up Study

Functional cure is an essential endpoint in the management of patients with chronic hepatitis B virus (HBV) infection. We evaluated the cumulative probability and predictors of functional cure in patients with chronic HBV infection after hepatitis B e antigen (HBeAg)-seroconversion. We retrospectively analyzed 413 (249 males and 164 females) initially HBeAg-positive chronic HBV-infected patients, who were followed up for a mean of 26.36 ± 0.53 years. All underwent HBeAg-seroconversion during follow-up. A functional cure was defined as durable HBsAg and HBV DNA loss without antiviral treatment for more than 24 weeks. After 10,888 person-years of follow-up, the cumulative probability of functional cure was 14.53% (n = 60). There were 24 (40%) subjects with functional cure after antiviral therapy. The annual functional cure rate was 0.55% per perperson-year, and increased to 0.96% per person-year after HBeAg-seroconversion. In subjects with functional cure, the HBsAg and HBV DNA titers after HBeAg-seroconversion were positively correlated with the time to functional cure (P < .001 and < .001, respectively). Multivariate Cox proportional hazard analysis of the cohort revealed that HBeAg-seroconversion at < 18 years of age, high genetic barrier nucleos(t)ide analogue(s) therapy before HBeAg-seroconversion, and a serum HBsAg titer < 1,000 IU/mL at 18 months after HBeAg-seroconversion were significant predictors of functional cure (P < .001, .001, and .001, respectively). In a cohort of chronic HBV-infected patients with long-term follow-up, HBeAg-seroconversion in childhood, high genetic barrier nucleos(t)ide analogue(s) therapy, and low HBsAg titers after HBeAg-seroconversion were significant predictors of functional cure.

Tracking KP.2 SARS-CoV-2 Variant in India and the Clinical Profile of KP.2 Cases in Maharashtra, India.

Following the emergence of the JN.1 SARS-CoV-2 variant, variants with key mutations in the spike protein, such as L455F, F456L, and R346T, were identified. In early January 2024, the KP.2 (JN.1.11.1.2) variant was first identified in clinical samples. Its increasing global prevalence has raised concerns over its transmission and clinical impact. The study investigates KP.2*'s (*indicates KP.2 and all its sub-lineages) spread and clinical severity in Maharashtra. This study involved 5,173 Indian SARS-CoV-2 whole genome sequences with collection dates between November 1, 2023 and June 24, 2024. Lineage analysis of sequences was performed using Nextclade software (version 3.8.0). Telephonic interviews were conducted to confirm the demographic details and obtain clinical information on the KP.2* cases. The obtained data were recorded and analyzed using Microsoft® Excel (Microsoft Corporation, Redmond, WA). Among the 5,173 sequences analyzed, JN.1* appeared as the predominant lineage (65.96%, 3412/5173), followed by KP.2* (7.83%, 405/5173) and KP.1* (3.27%, 169/5173). In India, KP.2* was first detected on December 2, 2023, in Odisha. The majority of KP.2* sequences were from Maharashtra (248/405, 61.23%), followed by West Bengal (38/405, 9.38%), Gujarat (27/405, 6.67%), and Rajasthan (24/405, 5.93%). Maharashtra reported its first KP.2* sequences on January 24, 2024. The clinical study included 160 cases of the KP.2* variant from Maharashtra. Of these, 95.63% (153/160) presented with mild symptoms, such as fever (108/160, 67.50%), cold (87/160, 54.38%), cough (80/160, 50%), sore throat (44/160, 27.5%), body ache (43/160, 26.88%), and fatigue (42/160, 26.25%). About 33.13% (53/160) of the cases required institutional quarantine or hospitalization, with the rest managed at home. Among those hospitalized, 50.94% (27/53) received conservative treatment, while 49.06% (26/53) needed supplemental oxygen, steroids, or antiviral therapy. Regarding the vaccination status, 89.38% (143/160) of the cases had received at least one dose of the COVID-19 vaccine, whereas 10% (16/160) were unvaccinated, with the majority of the unvaccinated being children aged zero to nine years (7/16, 43.75%). The overall recovery rate for KP.2* cases was 99.38% (159/160), with only 0.62% (1/160) succumbing to the disease. The KP.2 variant has become the dominant SARS-CoV-2 variant in India and Maharashtra. Despite the affected individuals experiencing mild symptoms, studies have shown lower neutralization titers and high infectivity due to FLiRT mutations, suggesting KP.2's potential rise to global dominance.

Gene editing of pigs to control influenza A virus infections

ABSTRACT Proteolytic activation of the haemagglutinin (HA) glycoprotein by host cellular proteases is pivotal for influenza A virus (IAV) infectivity. Highly pathogenic avian influenza viruses possess the multibasic cleavage site of the HA which is cleaved by ubiquitous proteases, such as furin; in contrast, the monobasic HA motif is recognized and activated by trypsin-like proteases, such as the transmembrane serine protease 2 (TMPRSS2). Here, we aimed to determine the effects of TMPRSS2 on the replication of pandemic H1N1 and H3N2 subtype IAVs in the natural host, the pig. The use of the CRISPR/Cas 9 system led to the establishment of homozygous gene edited (GE) TMPRSS2 knockout (KO) pigs. Delayed IAV replication was demonstrated in primary respiratory cells of KO pigs in vitro. IAV infection in vivo resulted in a significant reduction of virus shedding in the upper respiratory tract, and lower virus titers and pathological lesions in the lower respiratory tract of TMPRSS2 KO pigs as compared to wild-type pigs. Our findings support the commercial use of GE pigs to mitigate influenza A virus infection in pigs, as an alternative approach to prevent zoonotic influenza A transmissions from pigs to humans.

Leveraging Immunofocusing and Virus-like Particle Display to Enhance Antibody Responses to the Malaria Blood-Stage Invasion Complex Antigen PfCyRPA.

A vaccine protecting against malaria caused by Plasmodium falciparum is urgently needed. The blood-stage invasion complex PCRCR consists of the five malarial proteins PfPTRAMP, PfCSS, PfRipr, PfCyRPA, and PfRH5. As each subcomponent represents an essential and highly conserved antigen, PCRCR is considered a promising vaccine target. Furthermore, antibodies targeting the complex can block red blood cell invasion by the malaria parasite. However, extremely high titers of neutralizing antibodies are needed for this invasion-blocking effect, and a vaccine based on soluble PfRH5 protein has proven insufficient in inducing a protective response in a clinical trial. Here, we present the results of two approaches to increase the neutralizing antibody titers: (A) immunofocusing and (B) increasing the immunogenicity of the antigen via multivalent display on capsid virus-like particles (cVLPs). The immunofocusing strategies included vaccinating with peptides capable of binding the invasion-blocking anti-PfCyRPA monoclonal antibody CyP1.9, as well as removing non-neutralizing epitopes of PfCyRPA through truncation. Vaccination with PfCyRPA coupled to the AP205 cVLP induced nearly two-fold higher IgG responses compared to vaccinating with soluble PfCyRPA protein. Immunofocusing using a linear peptide greatly increased the neutralizing capacity of the anti-PfCyRPA antibodies. However, significantly lower total anti-PfCyRPA titers were achieved using this strategy. Our results underline the potential of a cVLP-based malaria vaccine including full-length PfCyRPA, which could be combined with other leading malaria vaccine antigens presented on cVLPs.