Introduction: Sickle cell disease (SCD) is prevalent in sub-Saharan Africa. Phenotypic diversity in patients with similar SCD genotypes may result from genetic and environmental factors. Nigeria has the highest SCD prevalence, with homozygous SCD (HbSS) being the most severe form. Stroke affects about 11% of children under 20 years with SCD (Ohene-Frempong, Weiner, et al. 1998), primarily ischemic, involving medium to large intracranial arteries. Specific single nucleotide polymorphisms have been linked to ischemic stroke risk in some populations. (Earley, Kelly et al. 2023). This study aimed to identify genetic factors associated with early-age large-vessel stroke in SCD using whole-exome sequencing (WES) in a Nigerian cohort. Methods: The protocol was approved by the IRBs of TJU, Nemours, and 3 Nigerian sites. Subjects with SCD who experienced large vessel stroke early in life (16 years or less) were enrolled, along with controls (SCD patients without stroke). Subjects were recruited from 3SCD clinics in Kano Metropolis, Nigeria. Inclusion criteria were confirmed SCD diagnosis (SS and Sβ0 thalassemia genotypes), abnormal transcranial doppler (TCD) measurements, and clinical evidence of stroke confirmed by MRI by age 16. Controls included SCD patients (SS and Sβ0) aged 16-26 years without clinical stroke and at least one normal TCD. All cases underwent Magnetic Resonance Angiography (MRA) to establish arteriopathy. Immediate family members of subjects >16 years (siblings and parents) were used per best practice trio analysis to annotate variants with appropriate Mendelian inheritance patterns. WES was performed using SureSelect XT HS (Agilent) and Human All Exon V7 Rev B capture probes for library preparation on all samples. Libraries were sequenced on a NextSeq 550 to 50M paired-end 150bp reads. Variants were called using the GATK suite of algorithms following best practice guidelines and annotated using the VarSeq algorithm, including AlphaMissense annotations. Results: The control group had a median age of 21 years, and the stroke group had a median age of 9 years. The stroke group had a higher proportion of males (60%) compared to controls (30%) (p < 0.05). Fifty percent of the stroke group and 73% of the controls had a history of acute chest syndrome. History of avascular necrosis (7.5%), heart disease (2.5%), and splenic sequestration (1.3%) were present only in controls. Malaria (1.3%), sepsis (2.5%), and hand-foot syndrome (59%) affected the stroke group. History of priapism (6.3%) and leg ulcers (10%) had similar rates in both groups. Using AlphaMissense annotations, nine genes were identified to have more damaging mutations in the stroke cohort compared to the control cohort (odds ratio > 1 and p < 0.05). Pathway enrichment analysis utilizing genes prioritized with an odds ratio > 1 identified cadherin signaling, cellular junction/adhesion, and WNT signaling as significant (p < 0.05). The role of cellular adhesion has been previously described in SCD stroke subjects (Oni, Brito et al. 2024). The genes that we found that showed significance in our analysis include ADAMTSL2, ADCY9, OR3A1, OR3A2, XRRA1, ABTB2, CLDN18, CPNE7, EIF3A, SLC7A6, UBA7, PDE6A, GLOD5, and PCDHA1. Conclusion: Genes in the ADCY9 and ADAMSL2 families have been reported in previous studies to be associated with ischemic stroke. Though the small sample size limits this study, it offers preliminary insights into the genetic and clinical determinants of stroke in SCD patients in Northern Nigeria. The identified candidate genes potentially hold biological significance for the stroke phenotype; however, additional research with a larger sample size is required to validate these associations. These findings underscore the need for further whole-exome sequencing studies in Nigerian patients with the stroke/arteriopathy phenotype, which may augment our understanding of this severe complication. An in-depth examination of the genetic modifiers associated with stroke in SCD could lead to enhanced predictive models and targeted preventive interventions, reducing the burden of stroke in affected individuals. Our team has identified additional datasets in the United States to help validate molecular signatures of interest, inspiring us to continue our work in this important field.
Development of a High-Throughput Multiplex Immunofluorescence Pipeline in Classic Hodgkin Lymphoma Whole Slide Formalin-Fixed Paraffin-Embedded Tissue Samples
Classic Hodgkin Lymphoma (cHL) is characterized by the presence of abnormal large cells known as Hodgkin Reed-Sternberg (HRS) cells. Curative intent chemotherapy has a 90% response rate, but for refractory patients, current immunotherapies remain insufficient. Ongoing research aims to enhance therapy and patient outcomes by focusing on the tumor microenvironment (TME), a complex environment that includes diverse non-malignant cells, including immune cells, which constitute a critical component of the TME. Utilizing multiplex analysis to comprehend these intricate interactions can pave the way for identifying novel strategies to combat cancer more effectively. CD30-targeted therapies and PD1/PDL1 inhibitors are under investigation clinically and could potentially benefit from adding checkpoint markers such as TIM-3 to enhance patient outcomes by addressing T-cell exhaustion. Such combination strategies will require assays and analysis strategies that can describe both spatial and multi-marker data. Multiplex immunofluorescence (mIF) is a valuable tool for analyzing spatial biology, patient selection, mechanism of action, pharmacodynamics and biomarker assays predictive of response. Describing the relationship between T cell exhaustion and response in cHL may guide the development of targeted treatments aimed at restoring the immune system's ability to recognize and eliminate cancer cells. Twenty-five to thirty percent of cHL patients with advanced stages do not respond to standard therapies. To understand the mechanisms of resistance, we developed a mIF panel (CD4, CD8, CD30, PD-1, PD-L1, and TIM3) for formalin-fixed and paraffin-embedded cHL tissues on the OPAL Tyramide Signal Amplification system and the Leica Bond RX. A set of commercially sourced cHL whole tissue samples (n=5) were used to develop and validate the panel, with qualitative evaluations by a Hematopathologist affirming that the mIF and 3, 3'-diaminobenzidine (DAB) staining yielded comparable results. Subsequently, a cohort of cHL samples (n=34) were stained and underwent exploratory image (Halo) and data (Microsoft Excel and R Studio) analyses. The image analysis strategy includes cell segmentation and phenotyping for all markers in the panel, identifying individual cell populations and multi-marker co-expressing cell populations. Additionally, spatial analysis describes the relationships between key phenotypes in the TME. The quantity of exhausted T cells, their average distance to HRS cells and the average count of exhausted T cells within different proximities of HRS cells will be presented. The development of this mIF assay for cHL demonstrates its consistent application at a mid-scale level across a diverse patient population with varying medical backgrounds and treatment histories. This approach provides a deeper understanding of immune response diversity and cellular composition within cHL. Future deployment of the panel against clinical trial samples with outcomes and responses will yield further insights.
Impact of a national dementia research consortium: The Canadian Consortium on Neurodegeneration in Aging (CCNA)
The Canadian Consortium on Neurodegeneration in Aging (CCNA) was created by the Canadian federal government through its health research funding agency, the Canadian Institutes for Health Research (CIHR), in 2014, as a response to the G7 initiative to fight dementia. Two five-year funding cycles (2014–2019; 2019–2024) have occurred following peer review, and a third cycle (Phase 3) has just begun. A unique construct was mandated, consisting of 20 national teams in Phase I and 19 teams in Phase II (with research topics spanning from basic to clinical science to health resource systems) along with cross-cutting programs to support them. Responding to the needs of researchers within the CCNA teams, a unique sample of 1173 deeply phenotyped patients with various forms of dementia was accrued and studied over eight years (COMPASS-ND). In the second phase of funding (2019–2024), a national dementia prevention program (CAN-THUMBS UP) was set up. In a short time, this prevention program became a member of the World Wide FINGERS prevention consortium. In this article, the challenges, successes, and impacts of CCNA in Canada and internationally are discussed. Short-term deliverables have occurred, along with considerable promise of impacts in the longer term. The creation of synergy, networking, capacity building, engagement of people with lived experience, and economies of scale have contributed to the considerable success of CCNA by all measures. CCNA is evidence that an organized “centrally-organized” approach to dementia research can catalyze important progress nationally and yield significant and measurable results.
Human Research Protections Basics for New Investigators
This chapter introduces human subjects research protections basics from a United States regulatory perspective. An introduction to the institutional review board (IRB) office provides descriptions of the types of research activities considered human subjects research (HSR) and not human subjects research (NHSR). Guidance is offered to new investigators for best practices in preparing for the ethical and responsible protection of human subjects in research and their data. Considerations for IRB policy and procedures, including suggestions for improving research protocol submissions for IRB review, are also offered.
Pleural space infection microbiology as assessed using a clinical sequencing-based assay:
Fusobacterium nucleatum
group,
Streptococcus intermedius,
and other oral normal microbiota are the most
ABSTRACT The definition of the microbiology of pleural space infection has been challenging due to the poor yield of conventional culture. Here, the results of a 16S ribosomal RNA gene PCR/sequencing assay performed on pleural fluid in routine clinical practice between August 2020 and January 2023 were evaluated. Amplified 16S rRNA gene DNA was submitted to Sanger sequencing and/or next-generation sequencing or results were reported as negative, depending on PCR crossing threshold value. In all, 496 pleural fluids were tested at Mayo Clinic Laboratories, with 227 positive results, including 57 from Mayo Clinic patients. Among the 57 Mayo Clinic patients, pleural space infection was community acquired in 48 (84%); Fusobacterium nucleatum group and/or Streptococcus intermedius were detected in 31/57 (54%) cases [including 28/48 (58%) community-acquired cases], with additional facultative and/or anaerobic species also found in various combinations in 17/31 (55%). Results of this study suggest that the most frequent microorganism profile involved in community-acquired pleural space infection may be a combination of F. nucleatum group and/or S. intermedius , with or without other normal microbiota. IMPORTANCE We describe here the most frequent microorganisms detected in community-acquired pleural space infection using a clinically performed sequencing-based assay. We found that the most common detection was the Fusobacterium nucleatum group and/or Streptococcus intermedius , with or without other normal microbiota. We propose the term e-FuSion (effusion with Fusobacterium nucleatum group, Streptococcus intermedius , and other oral normal microbiota) for this entity.
Macrolide-Resistant Mycoplasma pneumoniae, North Dakota 2024
Abstract A cluster of macrolide-resistant Mycoplasma pneumoniae -causing community-acquired pneumonia was observed in children in North Dakota in 2024. Suspicion was raised by non-response to macrolides, with confirmation via a polymerase-chain reaction assay. Prompt improvement occurred after the initiation of alternative antibiotics.
Prior immunity to
Ureaplasma urealyticum
protects against respiratory infection in immunosuppressed mice
ABSTRACT Ureaplasma species can cause systemic infections in immunocompromised hosts, including lung transplant recipients. Here, we investigated the impact of prior exposure to Ureaplasma urealyticum on the risk of U. urealyticum and Ureaplasma parvum infection in mice subjected to an immunosuppression regimen similar to that administered to solid organ transplant recipients. Mice were immunized with three intramuscular injections of U. urealyticum , with control mice injected with adjuvant only. Following immunization, mice received tacrolimus, mycophenolate mofetil, and methylprednisolone, and then were challenged with U. urealyticum or U. parvum intraperitoneally and intratracheally over 6 days. Relative U. urealyticum antibody levels in plasma were assessed over time, and lungs were harvested at sacrifice for bacterial load quantification, assessed using a color-changing unit assay. U. urealyticum antibody levels were higher in immunized compared with control animals ( P < 0.0001), even when animals were immunosuppressed. U. urealyticum and U. parvum lung burden was reduced in immunized compared with control mice (~6 log 10 reduction for U. urealyticum and <1 log 10 reduction for U. parvum ; P = 0.008 and 0.046, respectively). In summary, this study shows that prior exposure to live U. urealyticum provides some protection against infection with U. urealyticum . IMPORTANCE Ureaplasma -induced hyperammonemia syndrome is a rare but potentially deadly complication of solid organ transplantation, especially lung transplantation. The pathophysiology of this relatively recently recognized condition is poorly understood, and it is unclear what factors may influence patient susceptibility. This study investigates the possible protective effects of prior exposure to Ureaplasma urealyticum in a mouse model subjected to an immunosuppression regimen similar to that given to lung transplant recipients. The findings show that prior exposure could provide protection against Ureaplasma lung infection.
CTIM-14. EARLY SAFETY DATA FROM A RANDOMIZED, MULTICENTER, DOUBLE-BLIND, PHASE 2B STUDY OF IGV-001, AN AUTOLOGOUS CELL IMMUNOTHERAPY, VERSUS PLACEBO, IN NEWLY DIAGNOSED GLIOBLASTOMA (NDGBM)
Abstract Standard of care (SOC) for ndGBM begins with maximal safe resection followed by adjuvant radiotherapy and temozolomide, and maintenance temozolomide. IGV-001 is an autologous biologic-device combination immunotherapy for the treatment of ndGBM that consists of autologous GBM tumor cells and an antisense oligonucleotide against IGF-1R mRNA, irradiated and administered via biodiffusion chambers implanted in the abdomen. In a phase 1b study, IGV-001 was well tolerated without unexpected adverse events in subjects with ndGBM. Multiple efficacy signals were observed, including significant improvements in progression-free survival (PFS), overall survival (OS), radiographic evidence of tumor response, and changes in immune response biomarkers. Here, we present early safety data from the phase 2b randomized, multicenter, double-blind, placebo-controlled study (NCT04485949) designed to assess efficacy and safety of IGV-001 in subjects with ndGBM across 20 sites in the United States. After surgical resection, subjects were randomized 2:1 and treated with IGV-001 or placebo followed by SOC. The primary outcome is PFS, defined as the time from randomization to first progression, as determined by blinded central radiology review, or death. Secondary outcomes include OS, defined as the time from randomization to death due to any cause, and safety. As of May 22, 2024, 99 subjects were randomized and 95 implanted with IGV-001 or placebo plus SOC. A total of 39/45 (86.7%) subjects had sufficient follow-up time after initiated treatment with concurrent radiation and temozolomide. Nine of 72 randomized (12.5%) discontinued treatment, including 7 who stopped during the SOC treatment period. None ceased treatment for adverse events, protocol deviations, or death. A total of 11/72 (15.3%) randomized subjects discontinued the study after randomization. A review of blinded safety data did not show any emerging risk and supports no change to the benefit-risk profile of IGV-001 versus placebo. Updated data will be presented.
ARGONAUT-IV: susceptibility of carbapenemase-producing
Klebsiella pneumoniae
to the oral bicyclic boronate β-lactamase inhibitor ledaborbactam combined with ceftibuten
ABSTRACT Ledaborbactam (formerly VNRX-5236), a bicyclic boronate β-lactamase inhibitor with activity against class A, C, and D β-lactamases, is under development as an orally bioavailable etzadroxil prodrug (VNRX-7145) in combination with ceftibuten for the treatment of urinary tract infections. At ceftibuten breakpoints of ≤1 mg/L (EUCAST) and ≤8 mg/L (CLSI), 92.5% and 99.0%, respectively, of 200 carbapenem-resistant Klebsiella pneumoniae isolates, predominantly K. pneumoniae carbapenemase producing, were susceptible to ceftibuten-ledaborbactam (ledaborbactam tested at a fixed concentration of 4 mg/L) compared to 4.5% and 30.5%, respectively, to ceftibuten alone.
Association of Medicaid Expansion With Timely Receipt of Treatment and Survival Among Patients With HR-Negative, HER2-Positive Breast Cancer
Background: Hormone receptor (HR)–negative, HER2-positive (also called HER2-enriched) breast cancer has no worse prognosis than other breast cancers if it is treated with HER2-targeted therapy. Medicaid expansion under the Affordable Care Act (ACA) has been shown to be associated with improved access to care and outcomes for many cancers, but its association with receipt of care for HR-negative, HER2-positive breast cancer is unknown. We examined the association of Medicaid expansion with receipt of guideline-concordant treatment, time to treatment initiation, and survival among nonelderly women newly diagnosed with HR-negative, HER2-positive breast cancer. Patients and Methods: Women aged 18 to 62 years newly diagnosed with HR-negative, HER2-positive breast cancer between 2010 and 2018 were identified from the National Cancer Database. Outcomes included receipt of stage-based guideline-concordant treatment, timely initiation of treatment (<30 days, <60 days, <90 days from diagnosis), and stage-specific 2-year overall survival. A difference-in-differences (DID) analytic approach compared outcome changes following Medicaid expansion in expansion versus nonexpansion states. Multivariable linear probability models were used to estimate treatment outcomes, and flexible parametric survival models were used to evaluate survival, adjusting for sociodemographic and clinical confounders. Results: A total of 31,401 patients were included. Medicaid expansion was associated with an increase of 0.58 percentage points (ppt; 95% CI, 0.01–1.16) in receipt of guideline-concordant treatment overall, a 2.43-ppt (95% CI, 0.68–4.18) increase in initiating guideline-concordant treatment <60 days after diagnosis, and a 1.17-ppt (95% CI, 0.02–2.32) increase in 2-year survival rate. The increase in 2-year survival associated with Medicaid expansion was most prominent for patients with stage III disease (DID, 3.81; 95% CI, 0.82–6.80). Conclusions: Medicaid expansion was associated with improved care and survival for patients with HR-negative, HER2-positive breast cancer, an aggressive cancer type for which prognosis largely depends on access to effective treatment.