The Basel Institute for Immunology.

At the Centennial Exhibition of the Nobel Prize, the Nobel Foundation called it one of the ten cradles of creativity. The journal Nature likened its ideals to those of the French revolution--Liberté, Egalité, Fraternité--and called it a paradise devoted to the science of immune systems: the Basel Institute for Immunology (BII). Founded by Roche in 1968, inaugurated in 1971, and closed in 2000, it was home to almost 450 scientific members, over 1,000 scientific visitors, and nearly 100 scientific advisors from more than 30 countries who worked in complete academic freedom and without commercial motives on over 3,500 projects, publishing more than 3,200 scientific papers, almost all of them on the structure and functions of immune systems of different species. This review contains a first collection of historical facts and dates that describe the background of the exceptionally successful performance and the strong scientific impact of the institute on the field of immunology.

TOR, the Gateway to Cellular Metabolism, Cell Growth, and Disease.

Michael N. Hall is this year's recipient of the Lasker Basic Medical Research Award for the identification of the target of rapamycin, TOR. TOR is a master regulator of the cell's growth and metabolic state, and its dysregulation contributes to a variety of diseases, including diabetes, obesity, neurodegenerative disorders, aging, and cancer, making the TOR pathway an attractive therapeutic target.

Monitoring hiring discrimination through online recruitment platforms.

Women (compared to men) and individuals from minority ethnic groups (compared to the majority group) face unfavourable labour market outcomes in many economies1,2, but the extent to which discrimination is responsible for these effects, and the channels through which they occur, remain unclear3,4. Although correspondence tests5-in which researchers send fictitious CVs that are identical except for the randomized minority trait to be tested (for example, names that are deemed to sound 'Black' versus those deemed to sound 'white')-are an increasingly popular method to quantify discrimination in hiring practices6,7, they can usually consider only a few applicant characteristics in select occupations at a particular point in time. To overcome these limitations, here we develop an approach to investigate hiring discrimination that combines tracking of the search behaviour of recruiters on employment websites and supervised machine learning to control for all relevant jobseeker characteristics that are visible to recruiters. We apply this methodology to the online recruitment platform of the Swiss public employment service and find that rates of contact by recruiters are 4-19% lower for individuals from immigrant and minority ethnic groups, depending on their country of origin, than for citizens from the majority group. Women experience a penalty of 7% in professions that are dominated by men, and the opposite pattern emerges for men in professions that are dominated by women. We find no evidence that recruiters spend less time evaluating the profiles of individuals from minority ethnic groups. Our methodology provides a widely applicable, non-intrusive and cost-efficient tool that researchers and policy-makers can use to continuously monitor hiring discrimination, to identify some of the drivers of discrimination and to inform approaches to counter it.

The impact of marriage equality campaigns on stress: Did a Swiss public vote get under the skin?

Lesbian, gay, bisexual, trans, intersex, and queer (LGBTIQ+) individuals encounter persistent structural inequalities and discrimination that can lead to detrimental psychological and physiological health outcomes. Amid evolving legal landscapes, little attention has been directed toward understanding the physiological health effects of societal shifts on these communities. This study aims to explore the impact of a national marriage equality vote and associated debates on psychological and biological stress among LGBTIQ+ individuals and cisgender, heterosexual, endosex individuals (termed cis-heterosexual) in Switzerland. We gathered longitudinal survey and biological data collected in hair samples among LGBTIQ+ and cis-heterosexual individuals before, during, and after the 2021 national vote (survey data: NT1T2 = 954; NT2T3 = 880; biological data: NT1T2 = 393; NT2T3 = 354). Preregistered analyses reveal a notable increase in biological stress levels (i.e., cortisol and cortisone levels), but not perceived stress, among both LGBTIQ+ as well as cis-heterosexual individuals who were close to them during the campaign. Results further point out the negative impacts of the campaign against marriage equality (i.e., no-campaign) on LGBTIQ+ individuals' biological stress levels as well as on those of their allies. These effects were, however, moderated by exposure to the campaign for marriage equality (i.e., yes-campaign), indicating the powerful buffering effects of the yes-campaign on the impact of discrimination on individuals' health. However, these positive effects appear to come at a cost, potentially impacting the well-being of individuals engaged in advocating for the yes-campaign. This research underscores the lasting impact of political campaigns on individuals' health.

Transitions in development: an interview with Margherita Turco.

Margherita Turco is a group leader at the Friedrich Miescher Institute for Biomedical Research (FMI) in Basel, Switzerland, where she uses organoid technologies to investigate human placental development. We met with Margherita over Zoom to discuss her career path so far. She told us how her early interest in reproductive technologies led her to a postdoctoral position in Cambridge, UK, where she derived the first human placental and uterine organoids and established her independent research group.

A Case for a Human Immuno-Peptidome Project Consortium.

A multidisciplinary group of researchers gathered at the Hönggerberg Campus at ETH Zurich, Switzerland, for the first meeting on the Human Immuno-Peptidome Project (https://hupo.org/human-immuno-peptidome-project/). The long-term goal of this project is to map the entire repertoire of peptides presented by human leukocyte antigen molecules using mass spectrometry technologies, and make its robust analysis accessible to any immunologist. Here we outline the specific challenges identified toward this goal, and within this framework, describe the structure of a multipronged program aimed at addressing these challenges and implementing solutions at a community-wide level. Pillars of that program are: (1) method and technology development, (2) standardization, (3) effective data sharing, and (4) education. If successful, this community-driven endeavor might provide a roadmap toward new paradigms in immunology.

The SIB Swiss Institute of Bioinformatics Semantic Web of data.

The SIB Swiss Institute of Bioinformatics (https://www.sib.swiss/) is a federation of bioinformatics research and service groups. The international life science community in academia and industry has been accessing the freely available databases provided by SIB since its inception in 1998. In this paper we present the 11 databases which currently offer semantically enriched data in accordance with the FAIR principles (Findable, Accessible, Interoperable, Reusable), as well as the Swiss Personalized Health Network initiative (SPHN) which also employs this enrichment. The semantic enrichment facilitates the manipulation of large data sets from public databases and private data sets. Examples are provided to illustrate that the data from the SIB databases can not only be queried using precise criteria individually, but also across multiple databases, including a variety of non-SIB databases. Data manipulation, be it exploration, extraction, annotation, combination, and publication, is possible using the SPARQL query language. Providing documentation, tutorials and sample queries makes it easier to navigate this web of semantic data. Through this paper, the reader will discover how the existing SIB knowledge graphs can be leveraged to tackle the complex biological or clinical questions that are being addressed today.

Importation of Alpha and Delta variants during the SARS-CoV-2 epidemic in Switzerland: Phylogenetic analysis and intervention scenarios.

The SARS-CoV-2 pandemic has led to the emergence of various variants of concern (VoCs) that are associated with increased transmissibility, immune evasion, or differences in disease severity. The emergence of VoCs fueled interest in understanding the potential impact of travel restrictions and surveillance strategies to prevent or delay the early spread of VoCs. We performed phylogenetic analyses and mathematical modeling to study the importation and spread of the VoCs Alpha and Delta in Switzerland in 2020 and 2021. Using a phylogenetic approach, we estimated between 383-1,038 imports of Alpha and 455-1,347 imports of Delta into Switzerland. We then used the results from the phylogenetic analysis to parameterize a dynamic transmission model that accurately described the subsequent spread of Alpha and Delta. We modeled different counterfactual intervention scenarios to quantify the potential impact of border closures and surveillance of travelers on the spread of Alpha and Delta. We found that implementing border closures after the announcement of VoCs would have been of limited impact to mitigate the spread of VoCs. In contrast, increased surveillance of travelers could prove to be an effective measure for delaying the spread of VoCs in situations where their severity remains unclear. Our study shows how phylogenetic analysis in combination with dynamic transmission models can be used to estimate the number of imported SARS-CoV-2 variants and the potential impact of different intervention scenarios to inform the public health response during the pandemic.

HLA Associations of Intrathecal IgG Production against Specific Viruses in Multiple Sclerosis.

OBJECTIVE: Specific human leucocyte antigen (HLA) alleles are not only associated with higher risk to develop multiple sclerosis (MS) and other autoimmune diseases, but also with the severity of various viral and bacterial infections. Here, we analyzed the most specific biomarker for MS, that is, the polyspecific intrathecal IgG antibody production against measles, rubella, and varicella zoster virus (MRZ reaction), for possible HLA associations in MS. METHODS: We assessed MRZ reaction from 184 Swiss patients with MS and clinically isolated syndrome (CIS) and 89 Swiss non-MS/non-CIS control patients, and performed HLA sequence-based typing, to check for associations of positive MRZ reaction with the most prevalent HLA alleles. We used a cohort of 176 Swedish MS/CIS patients to replicate significant findings. RESULTS: Whereas positive MRZ reaction showed a prevalence of 38.0% in MS/CIS patients, it was highly specific (97.7%) for MS/CIS. We identified HLA-DRB1*15:01 and other tightly linked alleles of the HLA-DR15 haplotype as the strongest HLA-encoded risk factors for a positive MRZ reaction in Swiss MS/CIS (odds ratio [OR], 3.90, 95% confidence interval [CI] 2.05-7.46, padjusted = 0.0004) and replicated these findings in Swedish MS/CIS patients (OR 2.18, 95%-CI 1.16-4.02, padjusted = 0.028). In addition, female MS/CIS patients had a significantly higher probability for a positive MRZ reaction than male patients in both cohorts combined (padjusted <0.005). INTERPRETATION: HLA-DRB1*15:01, the strongest genetic risk factor for MS, and female sex, 1 of the most prominent demographic risk factors for developing MS, predispose in MS/CIS patients for a positive MRZ reaction, the most specific CSF biomarker for MS. ANN NEUROL 2024;95:1112-1126.

Bayesian workflow for time-varying transmission in stratified compartmental infectious disease transmission models.

Compartmental models that describe infectious disease transmission across subpopulations are central for assessing the impact of non-pharmaceutical interventions, behavioral changes and seasonal effects on the spread of respiratory infections. We present a Bayesian workflow for such models, including four features: (1) an adjustment for incomplete case ascertainment, (2) an adequate sampling distribution of laboratory-confirmed cases, (3) a flexible, time-varying transmission rate, and (4) a stratification by age group. Within the workflow, we benchmarked the performance of various implementations of two of these features (2 and 3). For the second feature, we used SARS-CoV-2 data from the canton of Geneva (Switzerland) and found that a quasi-Poisson distribution is the most suitable sampling distribution for describing the overdispersion in the observed laboratory-confirmed cases. For the third feature, we implemented three methods: Brownian motion, B-splines, and approximate Gaussian processes (aGP). We compared their performance in terms of the number of effective samples per second, and the error and sharpness in estimating the time-varying transmission rate over a selection of ordinary differential equation solvers and tuning parameters, using simulated seroprevalence and laboratory-confirmed case data. Even though all methods could recover the time-varying dynamics in the transmission rate accurately, we found that B-splines perform up to four and ten times faster than Brownian motion and aGPs, respectively. We validated the B-spline model with simulated age-stratified data. We applied this model to 2020 laboratory-confirmed SARS-CoV-2 cases and two seroprevalence studies from the canton of Geneva. This resulted in detailed estimates of the transmission rate over time and the case ascertainment. Our results illustrate the potential of the presented workflow including stratified transmission to estimate age-specific epidemiological parameters. The workflow is freely available in the R package HETTMO, and can be easily adapted and applied to other infectious diseases.

A hybrid empirical and parametric approach for managing ecosystem complexity: Water quality in Lake Geneva under nonstationary futures.

Severe deterioration of water quality in lakes, characterized by overabundance of algae and declining dissolved oxygen in the deep lake (DOB), was one of the ecological crises of the 20th century. Even with large reductions in phosphorus loading, termed "reoligotrophication," DOB and chlorophyll (CHL) have often not returned to their expected pre-20th-century levels. Concurrently, management of lake health has been confounded by possible consequences of climate change, particularly since the effects of climate are not neatly separable from the effects of eutrophication. Here, using Lake Geneva as an iconic example, we demonstrate a complementary alternative to parametric models for understanding and managing lake systems. This involves establishing an empirically-driven baseline that uses supervised machine learning to capture the changing interdependencies among biogeochemical variables and then combining the empirical model with a more conventional equation-based model of lake physics to predict DOB over decadal time-scales. The hybrid model not only leads to substantially better forecasts, but also to a more actionable description of the emergent rates and processes (biogeochemical, ecological, etc.) that drive water quality. Notably, the hybrid model suggests that the impact of a moderate 3°C air temperature increase on water quality would be on the same order as the eutrophication of the previous century. The study provides a template and a practical path forward to cope with shifts in ecology to manage environmental systems for non-analogue futures.

Deciphering Factors Linked With Reduced Severe Acute Respiratory Syndrome Coronavirus 2 Susceptibility in the Swiss HIV Cohort Study.

BACKGROUND: Factors influencing susceptibility to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain to be resolved. Using data from the Swiss HIV Cohort Study on 6270 people with human immunodeficiency virus (HIV) and serologic assessment for SARS-CoV-2 and circulating human coronavirus (HCoV) antibodies, we investigated the association of HIV-related and general parameters with SARS-CoV-2 infection. METHODS: We analyzed SARS-CoV-2 polymerase chain reaction test results, COVID-19-related hospitalizations, and deaths reported to the Swiss HIV Cohort Study between 1 January 2020 and 31 December 2021. Antibodies to SARS-CoV-2 and HCoVs were determined in prepandemic (2019) and pandemic (2020) biobanked plasma samples and compared with findings in HIV-negative individuals. We applied logistic regression, conditional logistic regression, and bayesian multivariate regression to identify determinants of SARS-CoV-2 infection and antibody responses to SARS-CoV-2 in people with HIV. RESULTS: No HIV-1-related factors were associated with SARS-CoV-2 acquisition. High prepandemic HCoV antibodies were associated with a lower risk of subsequent SARS-CoV-2 infection and with higher SARS-CoV-2 antibody responses on infection. We observed a robust protective effect of smoking on SARS-CoV-2 infection risk (adjusted odds ratio, 0.46 [95% confidence interval, .38-.56]; P < .001), which occurred even in previous smokers and was highest for heavy smokers. CONCLUSIONS: Our findings of 2 independent protective factors, smoking and HCoV antibodies, both affecting the respiratory environment, underscore the importance of the local immune milieu in regulating susceptibility to SARS-CoV-2.

Effect of Project Orbis participation by the Swiss regulator on submission gaps, review times, and drug approval decisions between 2020 and 2022: a comparative analysis.

BACKGROUND: Expedited market access for novel and efficacious drugs is warranted for patients. Since 2020, Swissmedic (The Swiss Agency for Therapeutic Products) has been participating in Project Orbis, a collaborative parallel-review programme launched by the US Food and Drug Administration (FDA) in 2019 to expedite patient access to cancer drugs. This programme allows regulatory agencies to remain independent in their decisions. We aimed to evaluate the effect of the first 2 years of Project Orbis from the Swissmedic perspective. METHODS: In this comparative analysis, we compared submission gap (time between submission at the FDA and Swissmedic), review time, approval and consensus decision rate, and the approved indications between Swissmedic and the FDA for marketing authorisation applications (MAAs) in oncology submitted to Swissmedic through Project Orbis (Orbis MAAs) or outside of Project Orbis (non-Orbis MAAs) from Jan 1, 2020, to Dec 31, 2021. Swissmedic review time was evaluated with a decision until June 30, 2022. For the decision comparison analysis, non-Orbis oncology MAAs submitted and evaluated from Jan 1, 2009, to Dec 31, 2018 (referred to as the pre-Orbis era) were also considered. Inferential statistics were done using Wilcoxon rank-sum test and the 95% CI for the median was based on binomial distribution. For each hypothesis testing, the significance level was set to 5%. No correction for multiple testing was performed. FINDINGS: We analysed the submission gap, review time, and regulatory decision for 31 Orbis MAAs and 41 non-Orbis MAAs during the Orbis era. The median submission gap was 33·0 days (95% CI 19·0-57·0) for Orbis MAAs versus 168·0 days (56·0-351·0) for non-Orbis MAAs (p<0·0001). The median review time at Swissmedic was 235·5 days (198·0-264·0) for Orbis MAAs versus 314·0 days (279·0-354·0) for non-Orbis MAAs (p=0·0002). Approval rates at Swissmedic were consistent between Orbis MAAs (20 [77%] of 26) and non-Orbis MAAs (31 [76%] of 41). The rate of consensus decisions between Swissmedic and the FDA was 21 (81%) of 26 for Orbis MAAs and 31 (76%) of 41 for non-Orbis MAAs. Swissmedic approval rates were lower for indication extensions than for new active substances for Orbis MAAs (13 [72%] of 18 vs seven [88%] of eight) and non-Orbis MAAs (17 [71%] of 24 vs 14 [82%] of 17). Divergent decisions between agencies were predominantly observed for indication extensions (11 [73%] of 15 divergent decisions). During the pre-Orbis era, Swissmedic approved 61 (88%) of 69 MAAs for new active substances. INTERPRETATION: Submission gap and review time for oncology applications at Swissmedic were significantly reduced by participation in Project Orbis, and approval consensus decisions were increased between agencies. These findings suggests that participating in Project Orbis could lead to faster patient access to drugs. FUNDING: None.

Antiretroviral Drug Exposure and Response in Obese and Morbidly Obese People With Human Immunodeficiency Virus (HIV): A Study Combining Modelling and Swiss HIV Cohort Data.

BACKGROUND: Obesity is increasingly prevalent among people with HIV (PWH) and can possibly result in suboptimal antiretroviral drug (ARV) exposure and response. However, this has not been thoroughly evaluated given that obese PWH are underrepresented in clinical trials. We performed virtual trials using physiologically based pharmacokinetic (PBPK) modelling combined with observed clinical data to provide ARV dosing guidance in obese individuals. METHODS: Each trial included a cohort of virtual adults with a body mass index (BMI) between 18.5 and 60 kg/m2. Therapeutic drug-monitoring data from the Swiss HIV Cohort Study (SHCS) were used to verify the predictive performance of the model. Subsequently, the model was applied to predict the pharmacokinetics of ARVs for different obesity classes. The association between ARV plasma concentrations and virological response was investigated in obese and nonobese individuals. RESULTS: The PBPK model predicted an average reduction in ARV exposure of ∼20% and trough concentrations of ∼6% in obese (BMI ≥30 kg/m2) compared with nonobese (BMI: 18.5-25 kg/m2) individuals, consistent with observed clinical data. Etravirine and rilpivirine were the most impacted, especially in individuals with BMI >40 kg/m2 whose trough concentrations were below the clinical target threshold. Obese PWH in the SHCS did not have a higher rate of unsuppressed viral load than nonobese PWH. CONCLUSIONS: The concentrations of ARVs are modestly reduced in obese individuals, with no negative impact on the virological response. Our data provide reassurance that standard doses of ARVs are suitable in obese PWH, including those who gained substantial weight with some of the first-line ARVs.

Immunogenicity of High-Dose Versus MF59-Adjuvanted Versus Standard Influenza Vaccine in Solid Organ Transplant Recipients: The Swiss/Spanish Trial in Solid Organ Transplantation on Prevention of Influenza (STOP-FLU Trial).

BACKGROUND: The immunogenicity of the standard influenza vaccine is reduced in solid-organ transplant (SOT) recipients, so new vaccination strategies are needed in this population. METHODS: Adult SOT recipients from 9 transplant clinics in Switzerland and Spain were enrolled if they were >3 months after transplantation. Patients were randomized (1:1:1) to a MF59-adjuvanted or a high-dose vaccine (intervention), or a standard vaccine (control), with stratification by organ and time from transplant. The primary outcome was vaccine response rate, defined as a ≥4-fold increase of hemagglutination-inhibition titers to at least 1 vaccine strain at 28 days postvaccination. Secondary outcomes included polymerase chain reaction-confirmed influenza and vaccine reactogenicity. RESULTS: A total of 619 patients were randomized, 616 received the assigned vaccines, and 598 had serum available for analysis of the primary endpoint (standard, n = 198; MF59-adjuvanted, n = 205; high-dose, n = 195 patients). Vaccine response rates were 42% (84/198) in the standard vaccine group, 60% (122/205) in the MF59-adjuvanted vaccine group, and 66% (129/195) in the high-dose vaccine group (difference in intervention vaccines vs standard vaccine, 0.20; 97.5% confidence interval [CI], .12-1); P < .001; difference in high-dose vs standard vaccine, 0.24 [95% CI, .16-1]; P < .001; difference in MF59-adjuvanted vs standard vaccine, 0.17 [97.5% CI, .08-1]; P < .001). Influenza occurred in 6% of the standard, 5% in the MF59-adjuvanted, and 7% in the high-dose vaccine groups. Vaccine-related adverse events occurred more frequently in the intervention vaccine groups, but most of the events were mild. CONCLUSIONS: In SOT recipients, use of an MF59-adjuvanted or a high-dose influenza vaccine was safe and resulted in a higher vaccine response rate. CLINICAL TRIALS REGISTRATION: Clinicaltrials.gov NCT03699839.

Predictors of Mortality of Streptococcal Bacteremia and the Role of Infectious Diseases Consultation: A Retrospective Cohort Study.

BACKGROUND: Streptococcal bacteremia is associated with high mortality. Thia study aims to identify predictors of mortality among patients with streptococcal bacteremia. METHODS: This retrospective study was conducted at the Lausanne University Hospital, Switzerland, and included episodes of streptococcal bacteremia among adult patients from 2015 to 2023. RESULTS: During the study period, 861 episodes of streptococcal bacteremia were included. The majority of episodes were categorized in the Mitis group (348 episodes; 40%), followed by the Pyogenic group (215; 25%). Endocarditis was the most common source of bacteremia (164; 19%). The overall 14-day mortality rate was 8% (65 episodes). The results from the Cox multivariable regression model showed that a Charlson comorbidity index >4 (P .001; hazard ratio [HR], 2.87; confidence interval [CI]: 1.58-5.22), Streptococcus pyogenes (P = .011; HR, 2.54;CI: 1.24-5.21), sepsis (P < .001; HR, 7.48; CI: 3.86-14.47), lower respiratory tract infection (P = .002; HR, 2.62; CI: 1.42-4.81), and absence of source control interventions within 48 hours despite being warranted (P = .002; HR, 2.62; CI: 1.43-4.80) were associated with 14-day mortality. Conversely, interventions performed within 48 hours of bacteremia onset, such as infectious diseases consultation (P < .001; HR, 0.29; CI: .17-.48) and appropriate antimicrobial treatment (P < .001; HR, .28; CI: .14-.57), were associated with improved outcome. CONCLUSIONS: Our findings underscore the pivotal role of infectious diseases consultation in guiding antimicrobial treatment and recommending source control interventions for patients with streptococcal bacteremia.

Time Trends in Causes of Death in People With HIV: Insights From the Swiss HIV Cohort Study.

BACKGROUND: Advancements in access to antiretroviral therapy (ART) and human immunodeficiency virus (HIV) care have led to a decline in AIDS-related deaths among people with HIV (PWH) in Switzerland. However, data on the ongoing changes in causes of death among PWH over the past 15 years are scarce. METHODS: We investigated all reported deaths in the Swiss HIV Cohort Study between 2005 and 2022. Causes of death were categorized using the Coding Causes of Death in HIV protocol. The statistical analysis included demographic stratification to identify time trends and logistic regression models to determine associated factors for the underlying cause of death. RESULTS: In total, 1630 deaths were reported, with 23.7% of individuals assigned female sex at birth. These deaths included 147 (9.0%) HIV/AIDS-related deaths, 373 (22.9%) due to non-AIDS, non-hepatic cancers, 166 (10.2%) liver-related deaths, and 158 (9.7%) cardiovascular-related deaths. The median age at death (interquartile range) increased from 45.0 (40.0-53.0) years in 2005-2007 to 61.0 (56.0-69.5) years in 2020-2022. HIV/AIDS- and liver-related deaths decreased, whereas deaths from non-AIDS, non-hepatic cancers increased and cardiovascular-related deaths remained relatively stable. CONCLUSIONS: The proportionally decreasing HIV/AIDS and liver-related deaths showcase the effectiveness of ART, comprehensive HIV patient care, and interventions targeting hepatitis C virus coinfection. Future research should focus on managing cancer and cardiovascular-related conditions as the new leading causes of death among PWH. Comprehensive healthcare strategies focusing on non-AIDS-related comorbid conditions, cancer management, and sustaining liver and cardiovascular health are needed to bridge the ongoing health disparities between PWH and the general population.

Mast seeding in European beech (Fagus sylvatica L.) is associated with reduced fungal sporocarp production and community diversity.

Mast seeding is a well-documented phenomenon across diverse forest ecosystems. While its effect on aboveground food webs has been thoroughly studied, how it impacts the soil fungi that drive soil carbon and nutrient cycling has not yet been explored. To evaluate the relationship between mast seeding and fungal resource availability, we paired a Swiss 29-year fungal sporocarp census with contemporaneous seed production for European beech (Fagus sylvatica L.). On average, mast seeding was associated with a 55% reduction in sporocarp production and a compositional community shift towards drought-tolerant taxa across both ectomycorrhizal and saprotrophic guilds. Among ectomycorrhizal fungi, traits associated with carbon cost did not explain species' sensitivity to seed production. Together, our results support a novel hypothesis that mast seeding limits annual resource availability and reproductive investment in soil fungi, creating an ecosystem 'rhythm' to forest processes that is synchronized above- and belowground.