About

Allison Bayer is an Associate Professor in the Department of Pathology, Immunology and Laboratory Medicine at the University of Florida College of Medicine. Her research focuses on immune regulation and immunotherapy, particularly in the context of type 1 diabetes. She has contributed to the development and evaluation of computationally designed IL-10, and her work includes studying protection against type 1 diabetes development in mice with specific genetic deletions. Bayer's research also explores the synergistic effects of insulin-like growth factor-1 and interleukin-2 in inducing regulatory T cells, as well as the use of immunosuppressive microparticles for local immunomodulation of allogeneic islet transplants.

Research topics

• Medicine
• Genetics
• Bioinformatics
• Internal medicine
• Family medicine
• Intensive care medicine
• Biology
• Microbiology

Selected publications

• Informant accuracy of IQCODE, AD8 and GPCOGi for diagnosis of dementia: does your friend know best?

  BMC Primary Care · 2025-04-15 · 1 citations

  articleOpen access

  BACKGROUND: Increasing numbers of people require evaluation for possible dementia. However, research on the accuracy of informant questionnaires in primary care remains limited. METHODS: This study assessed the diagnostic accuracy of IQCODE, AD8, and GPCOGi based on the informant's relationship to the patient. We recruited 240 participants from 21 general practices in South West England. The reference standard for a diagnosis of dementia was made by a specialist clinician using ICD-10 criteria. A threshold of greater than 3.3 on IQCODE, greater or equal to 2 on AD8 and less than 5 on the informant component of GPCOG was used to indicate an abnormal test. RESULTS: Of 238 participants with informant data, 131 had dementia, 60 had CIND, and 47 had normal cognition. Median informant age was 70 years (IQR 60 years to 78 years). 71% of informants were female and 56% were spouses. On all three questionnaires, compared to spouses, adult descendants tended to score participants more cognitively impaired, whereas friends scored participants less cognitively impaired. However, there was little evidence of difference by informant type once fully adjusted. Sensitivity by informant type ranged from 91 to 100% for IQCODE, 94-100% for AD8 and 99% to100% for GPCOGi. There was no significant difference in sensitivity by informant type. Specificity by informant type ranged from 25 to 79% for IQCODE, 13-75% for AD8 and 17-38% for GPCOGi. Adult descendants tended to have the lowest specificity at 25% (95% CI 10-47%) for IQCODE, 13% (95% CI 3-32%) for AD8 and 17% (95% CI 5-37%) for GPCOGi. Friends tended to have the highest specificity at 79% (95% CI 49-95%) for IQCODE, 75% (95% CI 48-93%) for AD8 and 38% (95% CI 15-64%) for GPCOGi. CONCLUSIONS: An informant of any relationship type, using IQCODE, AD8 or GPCOGi may be useful for ruling out dementia but not for ruling it in. We found no evidence of difference between spouse or adult descendants but friends performed significantly better overall on IQCODE and AD8.

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• Informant Accuracy of IQCODE, AD8 and GPCOGi for diagnosis of dementia: Does your friend know best?

  Research Square · 2024-07-19

  preprintOpen access
  PublisherOA PDFDOI

• 9343 Protection Against Type 1 Diabetes Development In Mice With 4E-BP2 Deletion

  Journal of the Endocrine Society · 2024-10-01

  articleOpen access

  Abstract Disclosure: V. Pita Grisanti: None. F. Pecanha: None. R. Louzada: None. M. Blandino: None. C. Jaramillo: None. N. Arenas: None. A. Bayer: None. E. Bernal-Mizrachi: None. Type 1 diabetes is an autoimmune disease characterized by β-cell destruction promoted by autoreactive T cells that acquire an effector inflammatory phenotype. 4E-BP1/2 proteins are translational repressors and downstream targets of mTORC1, a key regulator of metabolism. mTORC1 signaling disruption is implicated in human diseases including diabetes. Activation of 4E-BP2/eIF4E pathway by 4E-BP2 deletion promotes translation initiation, which induces β-cell expansion and proliferation and is crucial for the regulation of adaptive immunity. However, the involvement of 4E-BP2 in type 1 diabetes development has not been explored. Therefore, this study aimed to determine the role of 4E-BP2/eIF4E signaling in type 1 diabetes prevention by regulation of β-cell survival and immune modulation. To investigate the role of 4E-BP2/eIF4E axis in diabetes pathogenesis, we used the non-obese diabetic (NOD) mouse model as a type 1 diabetes model, and generated mice with global deletion of 4E-BP2 in the NOD background (4E-BP2KONOD). We assessed type 1 diabetes development, glucose homeostasis, pancreas morphometry and immune responses in male and female 4E-BP2KONOD and control NOD mice. We found that 4E-BP2KONOD exhibited reduced diabetes incidence in male but not female mice. Reduction in diabetes incidence in 4E-BP2KONOD male mice was associated with comparable degree of insulitis and β-cell proliferation, and with preserved β-cell mass compared to the control NOD mice. Glucose-stimulated insulin secretion of the islets, assessed in vitro by static incubation, was significantly higher in the 4E-BP2KONOD compared to the NOD control. Autoimmune responses were also evaluated by assessment of insulitis and characterization of T cell compartments, which showed a decrease in splenic CD8+ cytotoxic T cells and an increase in pancreatic regulatory T cell (Treg) infiltration mainly by increased Treg survival in 4E-BP2KONOD mice compared to control NOD. Finally, adoptive transfer studies demonstrated that lymphocytes derived from male 4E-BP2KONOD mice were less diabetogenic than those derived from control NOD mice. In conclusion, this study showed that activation of 4E-BP2/eIF4E axis in 4E-BP2KONOD male mice protects against type 1 diabetes development by dampening autoimmune responses and preserving β-cell mass. Targeting 4E-BP2 may provide a potential treatment for type 1 diabetes. Presentation: 6/1/2024

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• Predictors and prognosis of population-based subjective cognitive decline: longitudinal evidence from the Caerphilly Prospective Study (CaPS)

  BMJ Open · 2023-10-01 · 3 citations

  articleOpen access

  OBJECTIVES: To understand associations between the subjective experience of cognitive decline and objective cognition. This subjective experience is often conceptualised as an early step towards neurodegeneration, but this has not been scrutinised at the population level. An alternative explanation is poor meta-cognition, the extreme of which is seen in functional cognitive disorder (FCD). DESIGN: Prospective cohort (Caerphilly Prospective Study). SETTING: Population-based, South Wales, UK. PARTICIPANTS: This men-only study began in 1979; 1225 men participated at an average age of 73 in 2002-2004, including assessments of simple subjective cognitive decline (sSCD, defined as a subjective report of worsening memory or concentration). Dementia outcomes were followed up to 2012-2014. Data on non-completers was additionally obtained from death certificates and local health records. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was incident dementia over 10 years. Secondary outcome measures included prospective change in objective cognition and cross-sectional cognitive internal inconsistency (the existence of a cognitive ability at some times, and its absence at other times, with no intervening explanatory factors except for focus of attention). RESULTS: sSCD was common (30%) and only weakly associated with prior objective cognitive decline (sensitivity 36% (95% CI 30 to 42) and specificity 72% (95% CI 68 to 75)). Independent predictors of sSCD were older age, poor sleep quality and higher trait anxiety. Those with sSCD did not have excess cognitive internal inconsistency, but results suggested a mild attentional deficit. sSCD did not predict objective cognitive change (linear regression coefficient -0.01 (95% CI -0.13 to 0.15)) nor dementia (odds ratio 1.35 (0.61 to 2.99)) 10 years later. CONCLUSIONS: sSCD is weakly associated with prior objective cognitive decline and does not predict future cognition. Prior sleep difficulties and anxiety were the most robust predictors of sSCD. sSCD in the absence of objective decline appears to be a highly prevalent example of poor meta-cognition (ie, poor self-awareness of cognitive performance), which could be a driver for later FCD.

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• A Diagnostic Test Accuracy Study Investigating General Practitioner Clinical Impression and Brief Cognitive Assessments for Dementia in Primary Care, Compared to Specialized Assessment

  Journal of Alzheimer s Disease · 2023-09-07 · 4 citations

  articleOpen access

  BACKGROUND: Many health systems are interested in increasing the number of uncomplicated and typical dementia diagnoses that are made in primary care, but the comparative accuracy of tests is unknown. OBJECTIVE: Calculate diagnostic accuracy of brief cognitive tests in primary care. METHODS: We did a diagnostic test accuracy study in general practice, in people over 70 years who had consulted their GP with cognitive symptoms but had no prior diagnosis of dementia. The reference standard was specialist assessment, adjudicated for difficult cases, according to ICD-10. We assessed 16 index tests at a research clinic, and additionally analyzed referring GPs clinical judgement. RESULTS: 240 participants had a median age of 80 years, of whom 126 were men and 132 had dementia. Sensitivity of individual tests at the recommended thresholds ranged from 56% for GP judgement (specificity 89%) to 100% for MoCA (specificity 16%). Specificity of individual tests ranged from 4% for Sniffin' sticks (sensitivity 100%) to 91% for Timed Up and Go (sensitivity 23%). The 95% centile of test duration in people with dementia ranged from 3 minutes for 6CIT and Time and Change, to 16 minutes for MoCA. Combining tests with GP judgement increased test specificity and decreased sensitivity: e.g., MoCA with GP Judgement had specificity 87% and sensitivity 55%. CONCLUSIONS: Using GP judgement to inform selection of tests was an efficient strategy. Using IQCODE in people who GPs judge as having dementia and 6CIT in people who GPs judge as having no dementia, would be a time-efficient and accurate diagnostic assessment.The original protocol for the study is available at https://bmcfampract.biomedcentral.com/articles/10.1186/s12875-016-0475-2.

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• Amateur Boxing and Dementia: Cognitive Impairment Within the 35-Year Caerphilly Cohort Study.

  PubMed · 2022-05-01 · 4 citations

  article

  OBJECTIVE: To examine the long-term effects of amateur boxing in a representative population sample of men. DESIGN: The sample was examined every 5 years for 35 years. Cognition was assessed repeatedly from the third examination. Previous boxing experience and dementia were assessed at the fifth examination, and dementia assessed subsequently through medical records. SETTING AND ASSESSMENT OF RICK FACTORS: The Caerphilly Prospective Study investigates risk factors for a range of chronic diseases of diseases. These include life style and behavior, together with biological factors relevant to vascular disease. PARTICIPANTS: 1123 adult men aged 45 to 59 years at baseline, followed for 35 years. MAIN OUTCOME MEASURES: Cognitive impairment. RESULTS: A report by a subject of having boxed "seriously" when younger was associated with a 2-fold increase in cognitive impairment [odds ratio (OR) = 2.27; 95% confidence intervals = 1.18-4.38]. For amnestic (Alzheimer-like) impairment, this rises to OR = 2.78 (95% confidence limits 1.37-5.65). Having boxed is associated with an "advancement" in the onset of the dementia (4.8 years; 95% confidence limits 0.9-8.8 years). CONCLUSIONS: Amateur boxing is associated with an increased risk and an earlier onset of cognitive impairment and dementia.

  PublisherDOI

• Decline in Cognition from Mid-Life Improves Specificity of Mini-Mental State Examination: Diagnostic Test Accuracy in Caerphilly Prospective Study (CaPs)

  Journal of Alzheimer s Disease · 2022-08-19 · 1 citations

  articleOpen access

  BACKGROUND: The merit of using baseline cognitive assessments in mid-life to help interpret cross-sectional cognitive tests scores in later life is uncertain. OBJECTIVE: Evaluate how accuracy for diagnosing dementia is enhanced by comparing cross-sectional results to a midlife measure. METHODS: Cohort study of 2,512 men with repeated measures of Mini-Mental State Examination (MMSE) over approximately 10 years. Index test MMSE at threshold of 24 indicating normal, as a cross-sectional measure and in combination with decline in MMSE score from mid-life. Reference standard consensus clinical diagnosis of dementia by two clinicians according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). RESULTS: 1,150 men participated at phase 4 of whom 75 had dementia. A cross-sectional MMSE alone produced a sensitivity of 60% (50% to 70%) and specificity 95% (94% to 97%) with a threshold of≥24 points indicating normal. For lower-scoring men in late life, with cross sectional scores of < 22, combining cross-sectional AND a three-point or more decline over time had a sensitivity of 52% (39% to 64%) and specificity 99% (99% to 100%). For higher-scoring men in later life, with cross sectional scores < 26 combining cross-sectional OR decline of at least three points had a sensitivity of 98% (92% to 100%) and specificity 38% (32% to 44%). CONCLUSION: It may be helpful in practice to formally evaluate cognition in mid-life as a baseline to compare with if problems develop in future, as this may enhance diagnostic accuracy and classification of people in later life.

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• New insights into the genetic etiology of Alzheimer’s disease and related dementias

  Nature Genetics · 2022 · 2403 citations

  • Biology
  • Genetics
  • Bioinformatics

  Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele.

  DOI

• The Hemodynamic Stability of Critically Ill Pediatric Patients with Cardiovascular Diseases during Interhospital Air Ambulance Transport

  The Thoracic and Cardiovascular Surgeon · 2022-01-01

  article

  Background: This study aimed to determine the hemodynamic stability in critically ill pediatric patients with cardiovascular diseases during interhospital transport by air ambulance.

  PublisherDOI

• Probiotics to reduce antibiotic administration in care home residents aged 65 years and older: the PRINCESS RCT

  Efficacy and Mechanism Evaluation · 2021-04-01 · 3 citations

  articleOpen access

  Background Care homes are an increasingly important sector of care. Care home residents are particularly vulnerable to infections and are often prescribed antibiotics, driving antibiotic resistance. Probiotics may be a cheap and safe way to reduce antibiotic use. Efficacy and possible mechanisms of action are yet to be rigorously evaluated in this group. Objective The objective was to evaluate efficacy and explore mechanisms of action of a daily oral probiotic combination in reducing antibiotic use and infections in care home residents. Design This was a multicentre, parallel, individually randomised, placebo-controlled, double-blind trial, with qualitative evaluation and mechanistic studies. Setting A total of 310 care home residents were randomised from 23 UK care homes (from December 2016 to May 2018). Participants The participants were care home residents aged ≥ 65 years who were willing and able to give informed consent or, if they lacked capacity to consent, had a consultee to advise about participation on their behalf. Intervention A daily capsule containing an oral probiotic combination of Lactobacillus rhamnosus GG and Bifidobacterium animalis subsp. lactis BB-12 ( n = 155) or matched placebo ( n = 155) for up to 1 year. Main outcome measures The primary outcome was cumulative systemic antibiotic administration days for all-cause infections. Secondary outcomes included incidence and duration of infections, antibiotic-associated diarrhoea, quality of life, hospitalisations and the detection of resistant Enterobacterales cultured from stool samples (not exclusively). Methods Participants were randomised (1 : 1) to receive capsules containing probiotic or matched placebo. Minimisation was implemented for recruiting care home and care home resident sex. Care home residents were followed up for 12 months with a review by a research nurse at 3 months and at 6–12 months post randomisation. Care home residents, consultees, care home staff and all members of the trial team, including assessors and statisticians, were blinded to group allocation. Results Care home residents who were randomised to probiotic had a mean 12.9 cumulative systemic antibiotic administration days (standard error 1.49 days) ( n = 152) and care home residents randomised to placebo had a mean 12.0 cumulative systemic antibiotic administration days (standard error 1.50 days) ( n = 153) (adjusted incidence rate ratio = 1.13, 95% confidence interval 0.79 to 1.63; p = 0.495). There was no evidence of any beneficial effects on incidence and duration of infections, antibiotic-associated diarrhoea, quality of life, hospitalisations, the detection of resistant Enterobacterales cultured from stool samples or other secondary outcomes. There was no evidence that this probiotic combination improved blood immune cell numbers, subtypes or responses to seasonal influenza vaccination. Conclusions Care home residents did not benefit from daily consumption of a combination of the probiotics Lactobacillus rhamnosus GG and Bifidobacterium animalis subsp. lactis BB-12 to reduce antibiotic consumption. Limitations Limitations included the following: truncated follow-up of some participants; higher than expected probiotics in stool samples at baseline; fewer events than expected meant that study power may have been lower than anticipated; standard infection-related definitions were not used; and findings are not necessarily generalisable because effects may be strain specific and could vary according to patient population. Future work Future work could involve further rigorous efficacy, mechanisms and effectiveness trials of other probiotics in other population groups and settings regarding antibiotic use and susceptibility to and recovery from infections, in which potential harms should be carefully studied. Trial registration Current Controlled Trials ISRCTN16392920. Funding This project was funded by the Efficacy and Mechanism Evaluation (EME) programme, a MRC and NIHR partnership. This will be published in full in Efficacy and Mechanism Evaluation ; Vol. 8, No. 7. See the NIHR Journals Library website for further project information.

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Frequent coauthors

• John Gallacher

  University of Oxford

  167 shared

• Yoav Ben‐Shlomo

  University of Bristol

  164 shared

• Mark Fish

  Royal Devon & Exeter NHS Foundation Trust

  143 shared

• Shah Ebrahim

  69 shared

• Alexis Brice

  Sorbonne Université

  63 shared

• Sudha Seshadri

  Framingham Heart Study

  59 shared

• Gordon Wilcock

  58 shared

• Carol Brayne

  University of Cambridge

  57 shared

Labs

• Genomic LaboratoriesPI

Awards & honors

• Restoration of immune regulation in type 1 diabetes through…
• BREAKTHROUGH T1D – formerly JDRF Intl Combination therapy wi…
• UNIV OF MIAMI via NATL INST OF HLTH NIDDK GLUT1 Inhibition i…
• BREAKTHROUGH T1D – formerly JDRF Intl Role of mTORC1 signali…
• UNIV OF MIAMI via NATL INST OF HLTH NIDDK Use of dimethyl fu…