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BMJ Open Jul 2024Toxoplasmosis is a zoonotic parasitic disease caused by . It has a wide host range and is capable of vertical transmission in pregnant women, which may lead to...
BACKGROUND
Toxoplasmosis is a zoonotic parasitic disease caused by . It has a wide host range and is capable of vertical transmission in pregnant women, which may lead to undesirable pregnancy outcomes such as congenital malformations, miscarriage, premature birth and stillbirth. This study investigated the seroprevalence of infection among pregnant women attending the antenatal clinic at Namwala District Hospital in Southern Zambia.
METHODS
This was a cross-sectional study where blood was collected, and the serum was tested for IgG and IgM. A questionnaire was administered to participants on demographic characteristics and risk factors. Data were entered in Microsoft Excel and exported to STATA version 14 for analysis.
RESULTS
A total of 401 women were enrolled in the study from 3 March to 5 August 2021. The seroprevalence of IgG was 4.2% (n=17), while the seroprevalence of IgM was 0.7% (n=3). The median age was 27 (IQR: 24-30) years, and a larger proportion had primary-level education (n=223, 55.6%). The majority (81.6%) of the women were married. None of the risk factors investigated in this study were significant for infection.
CONCLUSION
There was a low seroprevalence of infection among pregnant women in the Namwala district of Southern Province, Zambia, and regular screening may not be warranted in this population. Continued research on toxoplasmosis is recommended to understand its epidemiology across Zambia.
Topics: Humans; Female; Zambia; Cross-Sectional Studies; Seroepidemiologic Studies; Adult; Pregnancy; Toxoplasmosis; Risk Factors; Toxoplasma; Young Adult; Immunoglobulin M; Antibodies, Protozoan; Pregnancy Complications, Parasitic; Immunoglobulin G; Prenatal Care
PubMed: 38950992
DOI: 10.1136/bmjopen-2024-084582 -
The Journal of Rheumatology Jul 2024Rheumatoid arthritis (RA) is prevalent in many Indigenous North American First Nations (FN) and tends to be seropositive, familial, and disabling, as well as associated... (Review)
Review
Rheumatoid arthritis (RA) is prevalent in many Indigenous North American First Nations (FN) and tends to be seropositive, familial, and disabling, as well as associated with highly unfavorable outcomes such as early mortality. The risk of developing RA is based on a perfect storm of gene-environment interactions underpinning this risk. The gene-environment interactions include a high frequency of shared epitope encoding HLA alleles, particularly , in the background population, and prevalent predisposing environmental factors such as smoking and periodontal disease. Together, these provide a compelling rationale for an RA prevention agenda in FN communities. Our research team has worked in partnership with several FN communities to prospectively follow the first-degree relatives of FN patients with RA, with the aim of better understanding the preclinical stages of RA in this population. We have focused on specific features of the anticitrullinated protein antibodies (ACPA) and other proteomic biomarkers as predictors of future development of RA. These studies have now led us to consider interventions having a favorable risk-benefit ratio if applied at a stage prior to a hypothetical "point of no return," when the autoimmunity potentially becomes irreversible. Based on a supportive mouse model and available human studies of curcumin, omega-3, and vitamin D supplements, we are undertaking studies where we screen communities using dried blood spot technology adapted for the detection of ACPA, and then enrolling ACPA-positive individuals in studies that use a combination of these supplements. These studies are guided by shared decision-making principles.
Topics: Humans; Anti-Citrullinated Protein Antibodies; Arthritis, Rheumatoid; Biomarkers; Gene-Environment Interaction; HLA-DRB1 Chains; Indians, North American
PubMed: 38950968
DOI: 10.3899/jrheum.2024-0369_dunlop-dottridge -
The Journal of Clinical Investigation Apr 2024Ectopic lymphoid structures (ELSs) in the rheumatoid synovial joints sustain autoreactivity against locally expressed autoantigens. We recently identified recombinant...
Ectopic lymphoid structures (ELSs) in the rheumatoid synovial joints sustain autoreactivity against locally expressed autoantigens. We recently identified recombinant monoclonal antibodies (RA-rmAbs) derived from single, locally differentiated rheumatoid arthritis (RA) synovial B cells, which specifically recognize fibroblast-like synoviocytes (FLSs). Here, we aimed to identify the specificity of FLS-derived autoantigens fueling local autoimmunity and the functional role of anti-FLS antibodies in promoting chronic inflammation. A subset of anti-FLS RA-rmAbs reacting with a 60 kDa band from FLS extracts demonstrated specificity for HSP60 and partial cross-reactivity to other stromal autoantigens (i.e., calreticulin/vimentin) but not to citrullinated fibrinogen. Anti-FLS RA-rmAbs, but not anti-neutrophil extracellular traps rmAbs, exhibited pathogenic properties in a mouse model of collagen-induced arthritis. In patients, anti-HSP60 antibodies were preferentially detected in RA versus osteoarthritis (OA) synovial fluid. Synovial HSPD1 and CALR gene expression analyzed using bulk RNA-Seq and GeoMx-DSP closely correlated with the lympho-myeloid RA pathotype, and HSP60 protein expression was predominantly observed around ELS. Moreover, we observed a significant reduction in synovial HSP60 gene expression followed B cell depletion with rituximab that was strongly associated with the treatment response. Overall, we report that synovial stromal-derived autoantigens are targeted by pathogenic autoantibodies and are associated with specific RA pathotypes, with potential value for patient stratification and as predictors of the response to B cell-depleting therapies.
Topics: Arthritis, Rheumatoid; Animals; Humans; Mice; Autoantigens; Germinal Center; Chaperonin 60; Autoantibodies; Autoimmunity; Male; Synoviocytes; Arthritis, Experimental; Female; B-Lymphocytes; Tertiary Lymphoid Structures
PubMed: 38950333
DOI: 10.1172/JCI169754 -
The Journal of Clinical Investigation May 2024In utero gene editing (IUGE) is a potential treatment for inherited diseases that cause pathology before or soon after birth. Preexisting immunity to adeno-associated...
In utero gene editing (IUGE) is a potential treatment for inherited diseases that cause pathology before or soon after birth. Preexisting immunity to adeno-associated virus (AAV) vectors and Cas9 endonuclease may limit postnatal gene editing. The tolerogenic fetal immune system minimizes a fetal immune barrier to IUGE. However, the ability of maternal immunity to limit fetal gene editing remains a question. We investigated whether preexisting maternal immunity to AAV or Cas9 impairs IUGE. Using a combination of fluorescent reporter mice and a murine model of a metabolic liver disease, we demonstrated that maternal anti-AAV IgG antibodies were efficiently transferred from dam to fetus and impaired IUGE in a maternal titer-dependent fashion. By contrast, maternal cellular immunity was inefficiently transferred to the fetus, and neither maternal cellular nor humoral immunity to Cas9 impaired IUGE. Using human umbilical cord and maternal blood samples collected from mid- to late-gestation pregnancies, we demonstrated that maternal-fetal transmission of anti-AAV IgG was inefficient in midgestation compared with term, suggesting that the maternal immune barrier to clinical IUGE would be less relevant at midgestation. These findings support immunologic advantages for IUGE and inform maternal preprocedural testing protocols and exclusion criteria for future clinical trials.
Topics: Animals; Female; Dependovirus; Mice; Pregnancy; Gene Editing; Humans; Immunoglobulin G; CRISPR-Associated Protein 9; Genetic Vectors; Maternal-Fetal Exchange; Antibodies, Viral; CRISPR-Cas Systems; Fetus; Immunity, Maternally-Acquired
PubMed: 38950310
DOI: 10.1172/JCI179848 -
The Journal of Clinical Investigation May 2024BackgroundRetinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) is a rare, autosomal dominant, universally fatal disease without...
BackgroundRetinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations (RVCL-S) is a rare, autosomal dominant, universally fatal disease without effective treatment options. This study explores the safety and preliminary efficacy of crizanlizumab, a humanized monoclonal antibody against P-selectin approved for the prevention of sickle cell crises, in slowing retinal nonperfusion and preserving vision in patients with RVCL-S.METHODSEleven patients with RVCL-S with confirmed exonuclease 3 prime repair exonuclease 1 (TREX1) mutations received monthly crizanlizumab infusions over 2 years. The study measured the nonperfusion index within 3 retinal zones and the total retina with fluorescein angiography, visual acuity, intraocular pressure (IOP), and optical coherence tomography central subfield thickness (CST) at baseline, 1 year, and 2 years. A mixed repeated-measures analysis was performed to assess the progression rates and changes from baseline.RESULTSEleven participants received crizanlizumab infusions. All of the participants tolerated crizanlizumab well, with 8 of 11 (72.7%) reporting mild adverse effects such as nausea, fatigue, and gastrointestinal symptoms. The change in total retinal nonperfusion was 7.22% [4.47, 9.97] in year 1 and -0.69% [-4.06, 2.68] in year 2 (P < 0.001). In the mid periphery, the change in nonperfusion was 10.6% [5.1, 16.1] in year 1 and -0.68% [-3.98, 5.35] in year 2 (P < 0.01), demonstrating a reduction in progression of nonperfusion in the second year of treatment. Visual acuity, IOP, and CST remained stable.CONCLUSIONCrizanlizumab has an acceptable safety profile. These results show promising potential for examining crizanlizumab in larger studies of RVCL-S and similar small-vessel diseases and for using the retina as a biomarker for systemic disease.Trial registrationClinicalTrials.gov NCT04611880.FUNDINGThe Clayco Foundation; DeNardo Education and Research Foundation Grant; Jeffrey T. Fort Innovation Fund; Siteman Retina Research Fund; unrestricted grant from Research to Prevent Blindness Inc.; National Heart,Lung, and Blood Institute (NHLBI), NIH (R01HL129241); National Institute of Neurological Disorders and Stroke (NINDS), NIH (RF1NS116565).
Topics: Humans; Male; Female; Adult; Antibodies, Monoclonal, Humanized; Middle Aged; Leukoencephalopathies; Exodeoxyribonucleases; Retinal Diseases; Phosphoproteins
PubMed: 38950286
DOI: 10.1172/JCI180916 -
Blood Transfusion = Trasfusione Del... Jun 2024Transfusion medicine is facing new challenges from therapies which interfere with pre-transfusional tests, such as monoclonal antibodies targeting blood-cell antigens....
BACKGROUND
Transfusion medicine is facing new challenges from therapies which interfere with pre-transfusional tests, such as monoclonal antibodies targeting blood-cell antigens. Anti-CD38 monoclonal antibodies, widely used to treat multiple myeloma, cause panreactivity of indirect antiglobulin test; this can be resolved by treating cells with dithiothreitol to disrupt the CD38 disulphide bonds expressed on red blood cell surfaces. Interference mitigation strategy with dithiothreitol, however, has some drawbacks: it entails losing the traceability of results and the denaturation of blood group systems sensitive to reducing agents; it takes time to perform and quality controls are lost.
MATERIALS AND METHODS
Panels were treated with 0.2 mol/L dithiothreitol and stored for 30 days with a commercial preservative solution. On day 30, we measured the hemolysis indices and ability to eliminate daratumumab and isatuximab interference in the treated cells using indirect antiglobulin test. We also tested the stability of erythrocyte antigenic structure by screening 42 samples with known antibodies; tests were repeated on day 1, 7, 15 and 30. All indirect antiglobulin testing was performed on gel card.
RESULTS
After 30 days from treatment, panels preserved in preservative solution showed hemolysis indices comparable to untreated panels: all cases of interference by anti-CD38 in pre-transfusional tests were successfully mitigated. All antibodies were detected after 30 days, except for KEL system antibodies, as expected, although there was a detectability of anti-Kell antibodies in high titer samples (the first detection in dithiothreitol-treated cells since 1983).
DISCUSSION
We propose the Extended Lifetime Protocol; a simple card-based method which is cheap and traceable, that combines the strengths of anti-CD38 mitigation strategies. It makes it possible to treat and store, at the same time, a sufficient volume of red blood cells, that can be used for the following 30 days, to avoid any delay in transfusional requests.
PubMed: 38949853
DOI: 10.2450/BloodTransfus.779 -
Polish Archives of Internal Medicine Jul 2024There is little data on the development of dermal lesions in patients with inflammatory bowel disease (IBD) treated with anti - tumor necrosis factor-α (anti-TNF-α),...
Dermal lesions associated with anti-tumor necrosis factor-α therapy in patients with inflammatory bowel disease: findings from an inflammatory bowel disease tertiary center in Poland.
INTRODUCTION
There is little data on the development of dermal lesions in patients with inflammatory bowel disease (IBD) treated with anti - tumor necrosis factor-α (anti-TNF-α), while their characteristics, clinical course, and impact on treatment are of great concern.
OBJECTIVES
The aim of this study is to assess the prevalence, risk factors, and clinical sequelae of dermal lesions in IBD patients treated with anti-TNF-α antibodies.
PATIENTS AND METHODS
This retrospective, single-center study evaluated 541 IBD patients treated with anti-TNF-α drugs and compared them with 688 IBD anti-TNF-α-naïve patients.
RESULTS
A significant higher prevalence of dermal lesions was noted during the anti-TNF-α therapy of 30.9% patients versus 16.4% (P <0.001). Risk factors for dermal lesions were higher body mass index (BMI), Crohn's disease located in the small intestine, and longer duration of therapy. Some types of dermal lesions were associated with anti-TNF-α therapy: infusion reactions and injection site reactions, cutaneous infection, psorasiform reactions, and lupus-like symptoms. Dermal lesions (alopecia, lupus-like symptoms, melanoma, and psoriasis) occurred in 5.9% of patients who discontinued or changed anti-TNF-α therapy.
CONCLUSIONS
We observed a higher prevalence of dermal lesions in patients with IBD undergoing anti-TNF-α therapy, although the development of such lesions rarely necessitated a change in or discontinuation of treatment. Patients with IBD should undergo regular dermatological follow-up, which may improve the detection of dermal lesions. Moreover, biological therapy in IBD patients requires close collaboration with an experienced dermatologist.
PubMed: 38949562
DOI: 10.20452/pamw.16789 -
BioRxiv : the Preprint Server For... Jun 2024Both endogenous antibodies and a subset of antibody therapeutics engage Fc gamma receptor (FcγR)IIIa / CD16a to stimulate a protective immune response. Increasing the...
Both endogenous antibodies and a subset of antibody therapeutics engage Fc gamma receptor (FcγR)IIIa / CD16a to stimulate a protective immune response. Increasing the FcγRIIIa/IgG1 interaction improves the immune response and thus represents a strategy to improve therapeutic efficacy. FcγRIIIa is a heavily glycosylated receptor and glycan composition affects antibody-binding affinity. Though our laboratory previously demonstrated that natural killer (NK) cell N-glycan composition affected the potency of one key protective mechanism, antibody-dependent cell-mediated cytotoxicity (ADCC), it was unclear if this effect was due to FcγRIIIa glycosylation. Furthermore, the structural mechanism linking glycan composition to affinity and cellular activation remained undescribed. To define the role of individual amino acid and N-glycan residues we measured affinity using multiple FcγRIIIa glycoforms. We observed stepwise affinity increases with each glycan truncation step with the most severely truncated glycoform displaying the highest affinity. Removing the N162 glycan demonstrated its predominant role in regulating antibody-binding affinity, in contrast to four other FcγRIIIa N-glycans. We next evaluated the impact of the N162 glycan on NK cell ADCC. NK cells expressing the FcγRIIIa V158 allotype exhibited increased ADCC following kifunensine treatment to limit N-glycan processing. Notably, an increase was not observed with cells expressing the FcγRIIIa V158 S164A variant that lacks N162 glycosylation, indicating the N162 glycan is required for increased NK cell ADCC. To gain structural insight into the mechanisms of N162 regulation, we applied a novel protein isotope labeling approach in combination with solution NMR spectroscopy. FG loop residues proximal to the N162 glycosylation site showed large chemical shift perturbations following glycan truncation. These data support a model for the regulation of FcγRIIIa affinity and NK cell ADCC whereby composition of the N162 glycan stabilizes the FG loop and thus the antibody-binding site.
PubMed: 38948809
DOI: 10.1101/2024.06.17.599285 -
BioRxiv : the Preprint Server For... Jun 2024SARS-CoV-2 virus has continued to evolve over time necessitating the adaptation of vaccines to maintain efficacy. Monoclonal antibodies (mAbs) against SARS-CoV-2 were a...
UNLABELLED
SARS-CoV-2 virus has continued to evolve over time necessitating the adaptation of vaccines to maintain efficacy. Monoclonal antibodies (mAbs) against SARS-CoV-2 were a key line of defense for unvaccinated or immunocompromised individuals. However, these mAbs are now ineffective against current SARS-CoV-2 variants. Here, we tested three aspects of αSARS-CoV-2 therapeutics. First, we tested whether Fc engagement is necessary for clearance of SARS-CoV-2. Secondly, we tested bi-specific killer engagers (BiKEs) that simultaneously engage SARS-CoV-2 and a specific Fc receptor. Benefits of these engagers include the ease of manufacturing, stability, more cell-specific targeting, and high affinity binding to Fc receptors. Using both mAbs and BiKEs, we found that both neutralization and Fc receptor engagement were necessary for effective SARS-CoV-2 clearance. Thirdly, due to ACE2 being necessary for viral entry, ACE2 will maintain binding to SARS-CoV-2 despite viral evolution. Therefore, we used an ACE2 decoy Fc-fusion or BiKE, instead of an anti-SARS-CoV-2 antibody sequence, as a potential therapeutic that would withstand viral evolution. We found that the ACE2 decoy approach also required Fc receptor engagement and, unlike traditional neutralizing antibodies against specific variants, enabled the clearance of two distinct SARS-CoV-2 variants. These data show the importance of Fc engagement for mAbs, the utility of BiKEs as therapies for infectious disease, and the effectiveness of the ACE2 decoy approach. With further studies, we predict combining neutralization, the cellular response, and this ACE2 decoy approach will benefit individuals with ineffective antibody levels.
ABBREVIATIONS
ACE2, scFv, mAb, BiKE, COVID-19, Fc, CD16, CD32b, CD64, d.p.i.
KEY POINTS
With equal dosing, both neutralization and Fc engagement are necessary for the optimal efficacy of antibodies and bi-specific killer engagers (BiKEs) against SARS-CoV-2. BiKEs can clear SARS-CoV-2 virus and protect against severe infection in the hACE2-K18 mouse model. ACE2 decoys as part of Fc-fusions or BiKEs provide clearance of two disparate SARS-CoV-2 variants.
PubMed: 38948747
DOI: 10.1101/2024.06.20.599956 -
Cancer Management and Research 2024As one of the most important breakthroughs in cancer therapy, immune checkpoint inhibitors have greatly prolonged survival of patients with breast cancer. However, their...
Efficacy and Safety of Chidamide in Combination with PD-1 Inhibitor and Radiotherapy for HER2-Negative Advanced Breast Cancer: Study Protocol of a Single Arm Prospective Study.
PURPOSE
As one of the most important breakthroughs in cancer therapy, immune checkpoint inhibitors have greatly prolonged survival of patients with breast cancer. However, their application and efficacy are limited, especially for advanced HER2-negative breast cancer. It has been reported that epigenetic modulation of the histone deacetylase (HDAC) inhibitor chidamide, as well as immune microenvironment modulation of radiotherapy are potentially synergistic with immunotherapy. Thus, the combination of chidamide, radiotherapy and immunotherapy is expected to improve prognosis of patients with advanced HER2-negative breast cancer.
PATIENTS AND METHODS
This is a single-arm, open, prospective clinical trial investigating the efficacy and safety of the combination of HDAC inhibitor chidamide, anti-PD-1 antibody sintilimab, and the novel immuno-radiotherapy, which aims to enhance efficacy of immunotherapy, in subsequent lines of therapy of HER2-negative breast cancer. Our study will include 35 patients with advanced breast cancer that has failed endocrine therapy and first-line chemotherapy. Participants will receive 30 mg of chidamide twice a week, 200 mg of sintilimab once every 3 weeks, combined with immuno-radiotherapy. Radiotherapy will be centrally 8 Gy for at least one lesion, and at least 1 Gy for the other lesions. We will complete three fractions of radiotherapy in one cycle. The primary endpoint is progression-free survival, and secondary endpoints are objective response rate, disease control rate and safety. Moreover, biomarkers including cytokines and lymphocyte subgroups will be explored.
CONCLUSION
As a single-arm clinical trial, the analysis of the influence of each single treatment is limited. Besides, our study is an open study, which involves neither randomization nor blinding. In spite of the abovementioned limitations, this prospective clinical trial will give an insight into subsequent lines of therapy of HER2-negative advanced breast cancer, prolong the survival or achieve long remission for these participants, and identify potential responders.
PubMed: 38948681
DOI: 10.2147/CMAR.S464677