Antibody Class Research Articles

Seroprevalence of Borrelia, Anaplasma, Bartonella, Toxoplasma, Mycoplasma, Yersinia, and Chlamydia in Human Population from Eastern Poland.

The epidemiological situation related to infectious diseases is influenced by many factors. To monitor actual trends in selected zoonoses, a total of 473 serum samples from farmers, forestry workers, and veterinarians were collected for serological examination. Anti-Borrelia burgdorferi sensu lato (s.l.) antibodies were tested with ELISA and Western blot (WB) tests; the detection of anti-Toxoplasma gondii antibodies was performed using an enzyme linked fluorescence assay (ELFA). Antibodies to bartonellosis, anaplasmosis, and chlamydiosis were determined by indirect immunofluorescent test (IFA), whereas antibodies to yersiniosis and mycoplasmosis were confirmed in the ELISA test. Positive or borderline results of antibodies against B. burgdorferi s.l. in the ELISA test were detected in 33.8% of the study population. The borderline or positive ELISA test results for at least one antibody class were confirmed by WB in 58.7% of cases. The IgG antibodies against Anaplasma phagocytophilum, Toxoplasma gondii, and Mycoplasma pneumoniae were detected in 9.6%, 51.7%, and 63.6% of samples, respectively. Antibodies against Yersinia spp., Bartonella henselae, and Chlamydia pneumoniae were found to vary between 43 and 47%.

IgA class switching enhances neutralizing potency against SARS-CoV-2 by increased antibody hinge flexibility.

IgA antibodies are critical components of the mucosal immune barrier, providing essential first-line defense against viral infections. In this study, we investigated the impact of antibody class switching on neutralization efficacy by engineering recombinant antibodies of different isotypes (IgA1, IgG1) with identical variable regions from SARS-CoV-2 convalescent patients. A potent, broad-spectrum neutralizing monoclonal antibody CAV-C65 exhibited a ten-fold increase in neutralization potency upon switching from IgG1 to IgA1 monomer. Structural analysis revealed that this antibody binds to two adjacent receptor binding domains on the spike protein. Enhanced neutralization by IgA1 was attributed to the combined effects of increased affinity, unique hinge region properties, and potential cross-linking of viral particles. Inhaled CAV-C65 IgA1 demonstrated prophylactic efficacy against lethal SARS-CoV-2 infection in hACE2 mice. These findings highlight the pivotal role of IgA in antiviral immunity and inform the development of IgA-based therapeutics.

Isolation and structure of broad SIV-neutralizing antibodies reveal a proximal helical MPER epitope recognized by a rhesus multi-donor class.

The membrane-proximal external region (MPER) of the HIV-1 envelope is a target for broadly neutralizing antibodies (bnAbs), and vaccine-elicited MPER-directed antibodies have recently been reported from a human clinical trial. In this study, we sought to identify MPER-directed nAbs in simian immunodeficiency virus (SIV)-infected rhesus macaques. We isolated four lineages of SIV MPER-directed nAbs from two SIV-infected macaques. The nAbs displayed low potency but up to 90% breadth on a 20-strain SIV panel. Crystal structures of representative nAbs in complex with SIV MPER peptides revealed the SIV antibodies to bind a helical epitope at the N-terminal (proximal) region of the MPER, defining a reproducible multi-donor class encompassing all four lineages. HIV-1 comparison showed that this class of SIV MPER-directed antibodies targets a helical region overlapping that targeted by human vaccine-elicited ones. Thus, a prevalent and reproducible class of SIV bnAbs recognizes an epitope similar to that recently observed in an HIV-1-vaccine trial.

Divergent evolution of opposite base specificity and single-stranded DNA activity in animal and plant AP endonucleases.

Apurinic/apyrimidinic (AP) endonucleases are key enzymes responsible for the repair of base-less nucleotides generated by spontaneous hydrolysis or as DNA repair intermediates. APE1, the major human AP endonuclease, is a druggable target in cancer and its biological function has been extensively studied. However, the molecular features responsible for its substrate specificity are poorly understood. We show here that, in contrast to APE1, its Arabidopsis ortholog ARP (apurinic endonuclease-redox protein) exhibits orphan base-dependent activity on double-stranded DNA and very poor AP cleavage capacity on single-stranded DNA (ssDNA). We found that these differences are largely a consequence of the variation at two DNA intercalating amino acids that have undergone divergent changes in the metazoan and plant lineages. Swapping the identity of the residue invading the minor groove is sufficient to switch the orphan base specificities of APE1 and ARP. The affinity for ssDNA is largely determined by the major groove invading residue, and swapping its identity switches the ability of APE1 and ARP to cleave AP sites in ssDNA. Importantly, we show that the critical residue for ssDNA cleavage is crucial for mammalian APE1 function in antibody class switch recombination, suggesting an evolutionary advantage for ssDNA activity. These findings provide new molecular insights into the evolution of AP endonucleases.

Structural Immunology of SARS-CoV-2.

The SARS-CoV-2 spike (S) protein has undergone significant evolution, enhancing both receptor binding and immune evasion. In this review, we summarize ongoing efforts to develop antibodies targeting various epitopes of the S protein, focusing on their neutralization potency, breadth, and escape mechanisms. Antibodies targeting the receptor-binding site (RBS) typically exhibit high neutralizing potency but are frequently evaded by mutations in SARS-CoV-2 variants. In contrast, antibodies targeting conserved regions, such as the S2 stem helix and fusion peptide, exhibit broader reactivity but generally lower neutralization potency. However, several broadly neutralizing antibodies have demonstrated exceptional efficacy against emerging variants, including the latest omicron subvariants, underscoring the potential of targeting vulnerable sites such as RBS-A and RBS-D/CR3022. We also highlight public classes of antibodies targeting different sites on the S protein. The vulnerable sites targeted by public antibodies present opportunities for germline-targeting vaccine strategies. Overall, developing escape-resistant, potent antibodies and broadly effective vaccines remains crucial for combating future variants. This review emphasizes the importance of identifying key epitopes and utilizing antibody affinity maturation to inform future therapeutic and vaccine design.

Direct Immunofluorescence in Oral Lichen Planus and Related Lesions: Sensitivity, Specificity, and Diagnostic Accuracy in a Single Diagnostic Center in Poland.

Objectives: Our study aimed to establish the basic reliability parameters of direct immunofluorescence test results in patients with oral lichen planus. Methods: We conducted an evaluation of individual antibody classes in the DIF and ELISA (BP180 antigen), comparing these results with the classical histopathological (HP) examination in a group of patients treated within the standard healthcare in our clinic. Results: Among 66 participants with oral changes indicative of LP, only 50% received histopathological confirmation of the LP diagnosis. Among those with a DIF profile entirely typical for LP (C3+, F+), 57.1% had a positive HP result. Fibrinogen deposits were identified in 42.4% and 36.4% of individuals with positive HP results for F1 and F2, respectively; 78.8% of patients with negative HP and 57.6% with positive HP exhibited no fibrinogen deposits. Simultaneous positivity for F1 and F2 occurred in all cases where F1 was positive. HP confirmed positive DIF for C3 in 50% of cases. Fibrinogen deposits demonstrated the highest diagnostic accuracy (61%). Sensitivity and specificity for fibrinogen deposits were 36% and 42% for F1 and 79% and 82% for F2. The positive predictive values were 67% for F1 and 67% for F2, while the negative predictive values were 58% for F1 and 56% for F2. Overall diagnostic accuracy was reported at 61% for F1 and 59% for F2. Conclusions: Our data indicate the complementarity of HP and immunological test results and the necessity of using both methods together in cases of doubt.

Anti-platelet factor 4 antibody class and subclass in patients with vaccine-induced immune thrombotic thrombocytopenia

Anti-platelet factor 4 antibody class and subclass in patients with vaccine-induced immune thrombotic thrombocytopenia

Comparative Analysis of C4d Deposition with The Severity, Laboratory Results and Histopathologic Scores in Lupus Nephritis

Background: Lupus nephritis (LN) is a serious complication of systemic lupus erythematosus (SLE) and evident in 60% of patients. Complement system and its product, complement component 4 degradation (C4d), plays an important role in the pathogenesis of LN. The aim is to determine the prognostic value of C4d detection in different classes of LN and correlation with laboratory results and histopathologic activity score. Methods: Thirty-five patients with LN were collected between January to September 2023. Blood levels of anti-nuclear antigens (ANA), anti-double stranded DNA antibody (Anti-dsDNA), C3, C4, and 24hr urine protein were measured. Renal tissue biopsy was examined regarding glomerular C4d antibody immunohistochemical staining and Classes of LN according to International society of nephrology/Renal Pathology Society (ISN/RPS). Results: Glomerular C4d was expressed in 40% of LN patients and was significantly correlated with urinary protein excretion (p=0.001) and Anti-dsDNA antibody (P=0.048), but not with LN classes or activity score or low complements. Conclusions: Glomerular C4d deposition of LN does not indicate the present disease activity but may help to identify a subset of patients with worse renal prognosis, providing insights about the therapeutic approaches for SLE with LN. Keywords: Lupus nephriti, glomerular C4d, proteinuria, Anti-double stranded DNA Antibody.

Switching from ligand to receptor anti-calcitonin gene-related peptide (CGRP) antibodies or vice versa in non-responders: A controlled cohort study.

Limited options exist for migraine prevention after stopping anti-calcitonin gene-related peptide monoclonal antibodies. A systematic review examining the benefits of switching between different classes (ligand vs. receptor monoclonal antibody) is essential, alongside well-designed real-world studies. In this cohort study 67 patients were included, who discontinued their first treatment with erenumab or fremanezumab. Patients (n = 31) switched to another monoclonal antibody class within 3 months, whilst those in the control group (n = 36) received standard care. Allocation to either group relied largely on the availability of alternative monoclonal antibody treatments, introducing pseudo-random allocation. Changes in monthly migraine days were compared between groups 3 months post-discontinuation of the first monoclonal antibody or initiation of a different monoclonal antibody class. A multivariate regression model was conducted that accounted for potential confounding factors. The groups were comparable at baseline and poor treatment response was the main reason for treatment discontinuation of the first monoclonal antibody. The switching cohort experienced a reduction of 3.9 monthly migraine days (95% confidence interval -6.4, -1.3, p = 0.004) compared with the control group. Transitioning to a different anti-calcitonin gene-related peptide monoclonal class yields reduction in monthly migraine days compared to returning to standard care for patients with inadequate initial treatment response.

The role of immunoglobins in atherosclerosis development; friends or foe?

Coronary artery disease, atherosclerosis, and its life-threatening sequels impose the hugest burden on the healthcare systems throughout the world. The intricate process of atherosclerosis is considered as an inflammatory-based disorder, and therefore, the components of the immune system are involved in different stages from formation of coronary plaques to its development. One of the major effectors in this way are the antibody producing entities, the B cells. These cells, which play a significant and unique role in responding to different stress, injuries, and infections, contribute differently to the development of atherosclerosis, either inhibitory or promoting, depending on the type of subsets. B cells implicate in both systemic and local immune responses of an atherosclerotic artery by cell-cell contact, cytokine production, and antigen presentation. In particular, natural antibodies bind to oxidized lipoproteins and cellular debris, which are abundant during plaque growth. Logically, any defects in B cells and consequent impairment in antibody production may greatly affect the shaping of the plaque and its clinical outcome. In this comprehensive review, we scrutinize the role of B cells and different classes of antibodies in atherosclerosis progression besides current novel B-cell-based therapeutic approaches that aim to resolve this affliction of mankind.

Mechanotransduction governs CD40 function and underlies X-linked hyper-IgM syndrome.

B cell maturation depends on cognate interactions between the T and B cells. Upon interaction with CD40 ligand (CD40L) on T cells, CD40 delivers costimulatory signals alongside B cell antigen receptor (BCR) signaling to regulate affinity maturation and antibody class switch. Mutations affecting CD40-CD40L interactions cause abnormal antibody responses in immunodeficiencies known as X-linked hyper-IgM syndrome (X-HIgM). Here, we study the CD40-mediated mechanotransduction in B cells, which likely occurs during their physical contacts with T cells. We found that CD40 forms catch bond with CD40L that lasts longer at larger forces, both B and T cells exert tension on CD40-CD40L bonds, and force enhances CD40 signaling and antibody class switch. X-HIgM CD40L mutations impair catch bond formation, suppress endogenous tension, and reduce force-enhanced CD40 signaling, leading to deficiencies in antibody class switch. Our findings highlight the role of mechanotransduction in CD40 function and provide insights into the mechanisms underlying X-HIgM syndrome.

Exploring B-cell epitope conservation and antigenicity shift in current COVID-19 variants: Analyzing spike-antibody interactions for therapeutic uses

SARS-CoV-2, responsible for the global COVID-19 pandemic, has undergone significant genetic changes, leading to various variants impacting transmissibility, severity, and vaccine efficacy. The methodology involved evaluating SARS-CoV-2 variants designated by WHO as Variants of Interest (VOIs) and Variants Under Monitoring (VUMs). Several noteworthy mutations including G446S, K417N, T478K, E484A, N501Y, and Y505H exhibit a strong pattern of convergent evolution across all these variants, particularly at antigenic sites within the spike protein. Conformational epitopes mapping and antigenicity shift analyses implicated epitope changes which were compared for therapeutic purposes. VUMs BA.2.86 and XBB.2.3 show significant antigenicity changes and epitope dynamics, correlating with high root mean square deviation values and epitope expansions or contractions. Nonsynonymous mutations are predominant in all variants, suggesting functional changes affecting transmissibility and immune evasion. VOIs XBB.1.5, BA.2.86, and CH.1.1 show high solvent-accessible surface area and radius of gyration, indicating structural expansion and increased epitope availability. In contrast, stable VOI EG.5.1 displays minimal structural changes and moderate epitope expansions. We evaluated two classes of antibodies for their effectiveness in neutralizing SARS-CoV-2 variants. Antibodies CC12.1 and P4A1 from Class I, alongside CV07-250, P5A-2G9, and MW05 from Class II, display strong binding across multiple variants, indicating broad neutralizing capabilities. Specifically, P4A1 shows the highest affinity for EG.5 and EG.5.1, while MW05 exhibits the strongest binding to XBB.1.5, CH.1.1, and XBB.2.3, highlighting their potent neutralization potential. This study aims to elucidate epitope variations in evolving SARS-CoV-2 strains, offering critical insights for developing targeted interventions against current challenges posed by the virus.

Associations vulvar lichen sclerosus with autoimmune thyroid diseases.

Vulvar lichen sclerosus (VLS) is defined as a chronic inflammatory skin disease that most often involves lesions on the mucous membranes of the vulva with a tendency to progress to the anal skin. The etiopathogenesis of VLS remains unknown and is likely multifactorial. Data emphasize the role of immunological factors - more than 25% of VLS cases coexist with autoimmune diseases. The purpose of the present study was to determine the correlation of the prevalence of anti-thyroid antibodies - IgG class antibodies against thyroid peroxidase and IgG class antibodies against thyroglobulin in women with vulvar lichen sclerosus, and the appropriateness of screening tests for autoimmune thyroid diseases in women with vulvar lichen sclerosus. Fifty women with vulvar lichen sclerosus were enrolled in the study. The control group consisted of 41 healthy women. A detailed medical history was taken with all patients, followed by laboratory determinations - anti-thyroid antibodies - IgG class antibodies against thyroid peroxidase and IgG class antibodies against thyroglobulin. Antibodies to thyroid peroxidase were present in 12% of the study group with vulvar lichen sclerosus and 4.88% of the control group, and this difference was not statistically significant (p = 0.41). Anti-thyroglobulin antibodies were detected in 4% of the patients with vulvar lichen sclerosus and 4.88% of the control group, and this difference was not statistically significant either (p = 0.76). The study did not confirm the association of VLS with autoimmune thyroid diseases. Undoubtedly, based on the data available in the literature, further studies are needed to determine the mechanisms behind the association between vulvar lichen sclerosus and autoimmune thyroid diseases.

BLOOD ANTI-SURFACE PROTEINS ECHOVIRUS 30 (ENTEROVIRUS, PICORNAVIRIDAE) ANTIBODIES IN RESIDENTS OF THE NIZHNY NOVGOROD REGION

Abstract Echovirus 30 (Е30) is an enterovirus that causes severe forms of serous meningitis. Over many years, E30 virus has caused serous meningitis outbreaks all over the world including Russia, but the status of anti-E30 population immunity remains unexplored. In 2022, the average percentage of all pediatric admission enterovirus cases in Russia was 97%; the most severe E30 infection cases were registered in children under 17 years of age. The virus capsid surface contains proteins VP1, VP2 and VP3 with homologous epitopes common to other enterovirus proteins, which allows them to be used as an antigen for antibody detection. The work was aimed at assessing frequency of different antibody classes specific to full-length recombinant E30 VP1, VP2 and VP3 proteins. 331 blood serum samples collected from 2 months-to 61 year-old residents of the Nizhny Novgorod region were used in the study. E30 VP1, VP2 and VP3 proteins were expressed in Escherichia coli, purified chromatographically and used antigenically for detection of IgA, IgG and IgM antibodies by using enzyme-linked immunosorbent immunoassay. Most study subjects had antibodies specific to only one or two of the E30 surface proteins. IgA, IgG and IgM antibodies to three recombinant proteins were detected simultaneously in 0.3%, 4.2% and 2.7% of cases. Totally, anti-E30 protein IgG antibodies were detected in 29.9% of cases. The maximum detection rate of antibodies (50.0%) was recorded in pediatric groups that decreased with age. IgG antibodies were found in 9.3% of the tested individuals. The detection rate (16.6%) peaked in the age group of children from 7 to 11 years. The IgM antibody-obtained data evidence that during the study period, almost one in every ten-study participant was infected with enteroviruses. The results of analyzing long-term immunity specific to enteroviral proteins showed the highest frequency of detected IgG antibodies in children that tended to decline with age as well as about continued E30 virus circulation in the Nizhny Novgorod region.

Human Anti-Glycan Reactivity is Driven by the Selection of B cells Utilizing Private Antibody Gene Rearrangements that are Affinity Maturated in Germinal Centers.

The human antibody repertoire is broadly reactive with carbohydrate antigens represented in the universe of all living things, including both the host/self- as well as the commensal microflora-derived glycomes. Here we have used BCR receptor cloning and expression together with single-cell transcriptomics to analyze the B cell repertoire to the ubiquitous N-acetyl-D-glucosamine (GlcNAc) epitope in human cohorts and dissect the immune phylogeny of this predominant class of antibodies. We find that circulating anti-GlcNAc B cells exhibiting canonical BMem phenotypes emerge rapidly after birth and couple this observation with evidence for germinal center-dependent affinity maturation of carbohydrate-specific B cell receptors in situ during early childhood. Direct analysis of individual B cell clonotypes reveals they exhibit strikingly distinct fine-specificity profiles for palettes of GlcNAc containing moieties. These results suggest that a generalized exposure to complex environmental glycans drives the steady state anti-glycan repertoire.

Human Herpesvirus-6B Infection and Alterations of Gut Microbiome in Patients with Fibromyalgia: A Pilot Study

Fibromyalgia (FM) is a chronic disorder characterized by widespread musculoskeletal pain often accompanied by fatigue, sleep disturbances, memory issues, and mood disorders. The exact cause of FM remains unknown, and diagnosis is typically based on a history of persistent widespread pain, as there are no objective biomarkers usable in diagnosis of this disorder available. The aim of this study was to identify measurable indicators specific to FM with potential as biomarkers. This study included 17 individuals diagnosed with FM and 24 apparently healthy persons. Using real-time polymerase chain reaction (qPCR), we detected the presence of human herpesvirus (HHV)-6A and B genomic sequences in DNA isolated from peripheral blood mononuclear cells (PBMCs) and buccal swabs. HHV-6-specific IgG and IgM class antibodies, along with proinflammatory cytokine levels, were measured using enzyme-linked immunosorbent assay (ELISA) and bead-based multiplex assays. Additionally, the gut microbiome was analyzed through next-generation sequencing. HHV-6B was more frequently detected in the PBMCs of FM patients. FM patients with a body mass index (BMI) of 30 or higher exhibited elevated cytokine levels compared to the control group with the same BMI range. Gut microbiome analysis revealed significant differences in both α-diversity and β-diversity between the FM and control groups, indicating a shift in species abundance in the FM group.

Новая коронавирусная инфекция COVID-19 и состояние гуморального иммунного ответа у пациентов с гематологическими злокачественными опухолями

AIM. To study the baseline condition of the humoral component in the adaptive immune system and its changes in patients with hematologic malignancies who received the standard chemotherapy with and without monoclonal antibodies (mAb) after a COVID-19 infection. MATERIALS & METHODS. The study enrolled 51 patients with hematologic malignancies (AL, NHL, cHL, MM, CMPN). They were treated at the NN Burdenko Main Military Clinical Hospital. Patients were aged 24–84 years (median 50.6 years); there were 14 women and 37 men. The control group consisted of 16 healthy medical professionals working at the hospital who had had COVID-19. The main group included a subgroup of patients (n = 21) treated with mAb chemotherapy. In all patients, blood serum was tested for anti-SARS-CoV-2 antibodies of different classes. RESULTS. Significant differences were identified while assessing the level of IgG antibodies to SARS-CoV-2 S1-protein in lymphoma and multiple myeloma patients (median 431 BAU/mL vs. 667 BAU/mL; p < 0.05) as well as in patients with lymphomas and chronic myeloproliferative neoplasms (median 431 BAU/mL vs. 705 BAU/mL; p < 0.05). The juxtaposition of the control (n = 16) and main (n = 51) groups showed that their median levels of anti-SARS-CoV-2 IgG antibodies did not differ and accounted for 15.7 units. In the groups of patients with (n = 21) and without (n = 30) mAb chemotherapy, by the semi-quantitative method, the median levels of IgM/IgG antibodies to the S1-protein receptor-binding domain and SARS-CoV-2 nucleocapsid proteins accounted for 10.1 units vs. 16.1 units (p < 0.05). In the same groups of patients, the quantitative method yielded the median levels of anti-SARS-CoV-2 S1-protein IgG antibodies of 433 BAU/mL and 595 BAU/mL, respectively (p < 0.05). CONCLUSION. Patients with hematologic malignancies show a decline in the levels of anti-SARS-CoV-2 S-protein IgG antibodies. Non-recipients of mAb chemotherapy have a higher level of anti-SARS-CoV-2 IgG antibodies. Patients with an indication for mAb chemotherapy (rituximab and obinutuzumab) need to be protected from COVID-19 by means of epidemiological preventive measures. One of them is anti-SARS-CoV-2 vaccination prior to mAb chemotherapy onset or post-exposure prophylaxis with recombinant humanized IgG mAbs tixagevimab + cilgavimab.

(Re-)Emergence of Oropouche Virus (OROV) Infections: Systematic Review and Meta-Analysis of Observational Studies.

Oropouche Virus (OROV; genus of Orthobunyavirus) is the causal agent of Oropouche Fever (OF). Due to the lack of specific signs and symptoms and the limited availability of diagnostic tests, the actual epidemiology of OROV infections and OF has been extensively disputed. In this systematic review with meta-analysis, a literature search was carried out in PubMed, Scopus, EMBASE, and MedRxiv in order to retrieve relevant articles on the documented occurrence of OROV infections. Pooled detection rates were then calculated for anti-OROV antibodies and virus detection (i.e., viral RNA detected by viral cultures and/or real-time polymerase chain reaction [RT-qPCR]). Where available, detection rates for other arboviruses (i.e., Dengue [DENV], Chikungunya [CHKV], and Zika Virus [ZIKV]) were calculated and compared to those for OROV. A total of 47 studies from South America and the Caribbean were retrieved. In individuals affected by febrile illness during OROV outbreaks, a documented prevalence of 0.45% (95% confidence interval [95%CI] 0.16 to 1.12) for virus isolation, 12.21% (95%CI 4.96 to 27.09) for seroprevalence (including both IgM and IgG class antibodies), and 12.45% (95%CI 3.28 to 37.39) for the detection of OROV-targeting IgM class antibodies were eventually documented. In the general population, seroprevalence was estimated to be 24.45% (95%CI 7.83 to 55.21) for IgG class antibodies. The OROV detection rate from the cerebrospinal fluids of suspected cases of viral encephalitis was estimated to be 2.40% (95%CI 1.17 to 5.03). The occurrence of OROV infections was consistently lower than that of DENV, CHKV, and ZIKV during outbreaks (Risk Ratio [RR] 24.82, 95%CI 21.12 to 29.16; RR 2.207, 95%CI 1.427 to 3.412; and RR 7.900, 95%CI 5.386 to 11.578, respectively) and in the general population (RR 23.614, 95%CI 20.584 to 27.129; RR 3.103, 95%CI 2.056 to 4.685; and RR 49.500, 95%CI 12.256 to 199.921, respectively). In conclusion, our study stresses the possibly high underestimation of OROV prevalence in the general population of South America, the potential global threat represented by this arbovirus infection, and the potential preventive role of a comprehensive "One Health approach".

Imatinib mesylate reduces c-MYC expression in double-hit lymphoma cells by suppressing inducible cytidine deaminase

BackgroundDouble-hit lymphoma (DHL) with c-MYC gene translocation is highly aggressive and has a poor prognosis. In DHL cells, activation-induced cytidine deaminase (AID) promotes antibody class switch recombination (CSR), ultimately leading to c-MYC gene translocation caused by Myc/IgH DNA double-strand breaks. However, currently there is still no method to suppress the expression of AID.MethodsIn this study, we compared the clinical significance of AID expression in DHL, Additionally, two human double-hit lymphoma cell lines were used to analyze the effect of imatinib mesylate on c-MYC in vitro, and the therapeutic effect was also evaluated in xenograft mouse models.ResultsImatinib mesylate downregulated the AID and c-MYC proteins in patients with chronic myelogenous leukemia associated with DHL. In addition, imatinib mesylate reduced AID and c-MYC expression in SU-DHL-4 and OCI-Ly18DHL cells. Imatinib mesylate exerted significant inhibitory effects on the proliferation and metastasis of SU-DHL-4 and OCI-Ly18 cells. Finally, imatinib mesylate reduced not only tumor burden in DHL mouse models, but also AID and c-MYC expression in vivo.ConclusionThese findings reveal that imatinib mesylate effectively reduces the carcinogenic function of c-MYC in DHL, providing novel strategies for developing therapies targeting c-MYC-driven DHL.Graphical abstract

Isolation and characterization of IgG3 glycan-targeting antibodies with exceptional cross-reactivity for diverse viral families.

Broadly reactive antibodies that target sequence-diverse antigens are of interest for vaccine design and monoclonal antibody therapeutic development because they can protect against multiple strains of a virus and provide a barrier to evolution of escape mutants. Using LIBRA-seq (linking B cell receptor to antigen specificity through sequencing) data for the B cell repertoire of an individual chronically infected with human immunodeficiency virus type 1 (HIV-1), we identified a lineage of IgG3 antibodies predicted to bind to HIV-1 Envelope (Env) and influenza A Hemagglutinin (HA). Two lineage members, antibodies 2526 and 546, were confirmed to bind to a large panel of diverse antigens, including several strains of HIV-1 Env, influenza HA, coronavirus (CoV) spike, hepatitis C virus (HCV) E protein, Nipah virus (NiV) F protein, and Langya virus (LayV) F protein. We found that both antibodies bind to complex glycans on the antigenic surfaces. Antibody 2526 targets the stem region of influenza HA and the N-terminal domain (NTD) region of SARS-CoV-2 spike. A crystal structure of 2526 Fab bound to mannose revealed the presence of a glycan-binding pocket on the light chain. Antibody 2526 cross-reacted with antigens from multiple pathogens and displayed no signs of autoreactivity. These features distinguish antibody 2526 from previously described glycan-reactive antibodies. Further study of this antibody class may aid in the selection and engineering of broadly reactive antibody therapeutics and can inform the development of effective vaccines with exceptional breadth of pathogen coverage.