Prebiotic utilisation provides Lactiplantibacillus plantarum a competitive advantage in vitro, but is not reflected by an increased intestinal fitness.

Synbiotics combine the concepts of probiotics and prebiotics to synergistically enhance the health-associated effects of both components. Previously, we have shown that the intestinal persistence of inulin-utilizing L. plantarum Lp900 is significantly increased in rats fed an inulin-supplemented, high-calcium diet. Here we employed a competitive population dynamics approach to demonstrate that inulin and GOS can selectively enrich L. plantarum strains that utilize these substrates for growth during in vitro cultivation, but that such enrichment did not occur during intestinal transit in rats fed a GOS or inulin-supplemented diet. The intestinal persistence of all L. plantarum strains increased irrespective of their prebiotic utilization phenotype, which was dependent on the calcium level of the diet. Analysis of fecal microbiota and intestinal persistence decline rates indicated that prebiotic utilization capacity did not selectively stimulate intestinal persistence in prebiotic supplemented diets. Moreover, microbiota and organic acid profile analyses indicate that the prebiotic utilizing probiotic strains are vastly outcompeted by the endogenous prebiotic-utilizing microbiota, and that the collective enhanced persistence of all L. plantarum strains is most likely explained by their well-established tolerance to organic acids.

Use of sacubitril/valsartan in patients with heart failure in primary care in Germany: the AURORA-HF noninterventional study.

BACKGROUND: Sacubitril/valsartan (Sac/Val) is the first angiotensin receptor-neprilysin inhibitor indicated for symptomatic chronic heart failure (HF) with reduced ejection fraction (HFrEF). Given most patients with HF in Germany are managed by general practitioners, AURORA-HF investigated the baseline characteristics and 1­year follow-up of patients starting Sac/Val in primary care in Germany. METHODS: This was a prospective, multicenter, observational study, with all treatment decisions independent of participation. The only inclusion criteria were adults (age ≥ 18 years) with symptomatic HFrEF. The study comprised four groups, depending on therapy on entry: initiation of (1) Sac/Val or (2) other HF therapy; and no change in HF regimen that (3) included or (4) did not include Sac/Val. Baseline data were captured for all groups; 1­year follow-up was recorded in groups 1 and 2. RESULTS: Of 1278 patients in the baseline analyses, 513 (40.1%) had newly started Sac/Val (449 [87.5%] completing the 1­year follow-up), 265 (20.7%) had newly started other HF regimens (245, 92.5%) with 1­year follow-up, while 249 with Sac/Val (19.5%) and 251 without Sac/Val (19.6%) patients had unchanged therapies. Patients treated with Sac/Val had a higher New York Heart Association (NYHA) class at baseline and more often a left ventricular ejection fraction (LVEF) < 35%. The only baseline parameter significantly correlating with Sac/Val discontinuation during the 1­year follow-up was diabetes mellitus (odds ratio: 2.44; 95% confidence interval: 1.14-5.24). In the Sac/Val group, 30.7% of patients were in NYHA class I/II on study entry, improving to 51.0% at 1­year follow-up. In the no Sac/Val group, the corresponding rates of NYHA I and II classes were 49.8% and 58.2%, respectively. The overall adverse event profile of Sac/Val was good, with only 6.0% patients experiencing serious adverse events leading to permanent discontinuation. CONCLUSION: In patients with symptomatic HFrEF treated in primary care, the group in whom Sac/Val was initiated was characterized by a higher NYHA class and lower LVEF compared to patients in whom Sac/Val was not initiated. Sac/Val was well tolerated, with a high proportion completing 1 year of therapy.

Personality systems interactions theory: an integrative framework complementing the study of the motivational and volitional dynamics underlying adjustment to chronic pain.

In the endeavor to advance our understanding of interindividual differences in dealing with chronic pain, numerous motivational theories have been invoked in the past decade. As they focus on relevant, yet different aspects of the dynamic, multilevel processes involved in human voluntary action control, research findings seem fragmented and inconsistent. Here we present Personality Systems Interactions theory as an integrative meta-framework elucidating how different motivational and volitional processes work in concert under varying contextual conditions. PSI theory explains experience and behavior by the relative activation of four cognitive systems that take over different psychological functions during goal pursuit. In this way, it may complement existing content-related explanations of clinical phenomena by introducing a functional, third-person perspective on flexible goal management, pain acceptance and goal maintenance despite pain. In line with emerging evidence on the central role of emotion regulation in chronic pain, PSI theory delineates how the self-regulation of positive and negative affect impacts whether behavior is determined by rigid stimulus-response associations (i.e., habits) or by more abstract motives and values which afford more behavioral flexibility. Along with testable hypotheses, multimodal interventions expected to address intuitive emotion regulation as a central process mediating successful adaptation to chronic pain are discussed.

-Bottlebrush Networks: A Primer for Advanced Architectures.

Bottlebrush networks (BBNs) are an exciting new class of materials with interesting physical properties derived from their unique architecture. While great strides have been made in our fundamental understanding of bottlebrush polymers and networks, an interdisciplinary approach is necessary for the field to accelerate advancements. This perspective aims to act as a primer to BBN chemistry and physics for both new and current members of the community. In addition to providing an overview of contemporary BBN synthetic methods, we developed a workflow and desktop application (LengthScale), enabling bottlebrush physics to be more approachable. We conclude by addressing several topical issues and asking a series of pointed questions to stimulate conversation within the community.

Statins use amidst the pandemic: prescribing, dispensing, adherence, persistence, and correlation with COVID-19 statistics in nationwide real-world data from Poland.

Background: Adherence to medications presents a significant challenge in healthcare. Statins, used in primary and secondary prevention of cardiovascular disease, are of particular importance for public health. The outbreak of the COVID-19 pandemic resulted in additional healthcare system-related barriers impeding the execution of therapies. This study aimed to assess the use of as well as adherence and persistence to statins in a national cohort of 38 million of Polish citizens during pandemic. Methods: A retrospective analysis of prescription and dispensation data for all statins users from the national payer organization covering the years 2020-2022 was conducted. Medication adherence was assessed using the Medication Possession Ratio, for persistence the 30-day cut-off was accepted. National data on COVID-19 cases and COVID-19 related deaths were obtained from ECDC. Results: The analysis identified 7,189,716 Polish citizens (approximately 19% of Polish population) who were dispensed at least 1 pack of statins within the study period. Over that time, there was a continuous significant increasing trend in prescribing and dispensing of statins. Despite a total increase of 18.9% in the number of prescribed tablets, the percentage of tablets dispensed remained similar, averaging 86%. Overall percentage of adherent patients was 48.2%. For a random sample of 100,000 patients, the mean period of continuous therapy in 2022 was 6.2+/- 5.3 months. During the lockdown period, the mean number of prescribed and dispensed tablets was lower by 6.8% and 5.9%, respectively (p < 0.05). However, fluctuations in the number of COVID-19 cases or COVID-19-related deaths per week had no major impact on the prescribing and dispensing of statins. Conclusion: Over the time of pandemic, there was a continuous increase in the number of statin tablets prescribed and dispensed in Poland. This suggests that, despite the potential limitations posed by COVID-19, access to statins remained easy, which may be attributed to the mass-scale implementation of the national e-prescription system. However, it is crucial to realise that approximately 1/7 of prescribed statin doses were never dispensed, and the overall levels of adherence and persistence were low. This underscores the necessity for concerted efforts to change this scenario in Poland.

Utilization of Ocrelizumab within Different Treatment Strategies for Multiple Sclerosis: A 5-Year Population-Based Study.

BACKGROUND: We aim to provide up-to-date real-world evidence on the persistence, adherence, healthcare resource utilization, and costs of multiple sclerosis (MS) by comparing ocrelizumab to other disease-modifying treatments (DMTs) and within different DMT sequences. METHODS: We included 3371 people with MS who first received or switched DMT prescriptions from January 2018 to December 2022; they were identified through hospital discharge records, drug prescriptions, and exemption codes from the Campania Region (South Italy). We calculated persistence (time from the first prescription to discontinuation or switching to another DMT), adherence (proportion of days covered (PDC)), DMT costs, and MS hospital admissions and related costs. RESULTS: The most frequently prescribed DMT was dimethyl fumarate (n = 815; age 38.90 ± 11.91 years; 69.5% females), followed by ocrelizumab (n = 682; age 46.46 ± 11.29 years; 56.3%); 28.8% of the patients treated with ocrelizumab were naïve to DMTs. Using ocrelizumab as a statistical reference, the risk of discontinuation was higher for other highly active (HR = 6.32; 95%CI = 3.16, 12.63; p < 0.01) and low-/medium-efficacy DMTs (HR = 10.10; 95%CI = 5.10, 19.77; p < 0.01); adherence was lower for other highly active DMTs (Coeff = -0.07; 95%CI = -0.10, -0.04; p < 0.01) and low-/medium-efficacy DMTs (Coeff = -0.16; 95%CI = -0.19, -0.14; p < 0.01). monthly DMT costs were higher for other highly active DMTs (Coeff = 77.45; 95%CI = 29.36, 125.53; p < 0.01) but lower for low-/medium-efficacy DMTs (Coeff = -772.31; 95%CI = -816.95, -727.66; p < 0.01). The hospital admissions and related costs of MS were similar between ocrelizumab, other highly active DMTs, and other low-/medium-efficacy DMTs, and with ocrelizumab as the first-line DMT after other highly active DMTs and after low-/medium-efficacy DMTs, which was possibly due to the low number of observations. CONCLUSIONS: From 2018 to 2022, ocrelizumab was among the most frequently prescribed DMTs, with 28.8% prescriptions to incident MS patients, confirming its relevance in clinical practice. Ocrelizumab was associated with the highest persistence and adherence, pointing towards its favorable benefit-risk profile. The costs of ocrelizumab were lower than those of other highly active DMTs.

The Hidden Enemy Within: Uncovering the Secrets of HIV Tissues Reservoirs and Current mRNA Vaccine Development.

Human Immunodeficiency Viruses (HIV) continue to pose a significant global health threat despite the availability of antiretroviral therapy (ART). As a retrovirus, HIV persists as a stable, integrated, and replication-competent provirus within a diverse array of long-lived cells for many years, often termed "latent reservoirs" in individuals. Thus, this review aims to furnish a comprehensive overview of diverse tissue reservoirs where HIV persists, elucidating their pathogenesis and advancement in their strategies for clinical management. Understanding the mechanisms underlying HIV persistence within tissue reservoirs is of significant interest in developing effective ART for suppressing the virus in the blood. In addition, we also discussed the ongoing mRNA HIV vaccine that has shown promising results in clinical trials to elicit broadly neutralizing antibodies and effective T-cell responses against HIV.

Naturally developed HPV16 antibodies and risk of newly detected cervical HPV infection outcomes.

Little is known about the protection conferred by antibodies from natural human papillomavirus (HPV) infection. Our objective was to evaluate the association between HPV16 seroreactivity and HPV16 redetection, newly detected HPV infections, and loss of HPV DNA detection during follow-up. We analyzed data from 2462 unvaccinated Brazilian women. HPV16 IgG and neutralizing antibodies at baseline were assessed by enzyme-linked immunosorbent assay (n = 1975) and by the pseudovirus-based papillomavirus neutralization assay (n = 487). HPV detection, genotyping, and viral load were assessed by PCR-based methods. The associations were analyzed by Cox proportional hazards models. We observed a positive association between HPV16 IgG seroreactivity and redetection of HPV16 infections. Age-adjusted hazard ratios (HR) with 95% confidence intervals (CI) ranged from 2.45 (1.04-5.74) to 5.10 (1.37-19.00). Positive associations were also observed between HPV16 IgG antibodies and (1) newly detected HPV infections by genotypes unrelated to HPV16 (age-adjusted HR [95% CI] = 1.32 [1.08-1.2]) and (2) loss of detection of HPV infections by genotypes unrelated to HPV16 (age-adjusted HR [95% CI] = 1.24 [1.03-1.50]). Naturally developed HPV16 antibodies do not prevent recurrent HPV infections. Overall HPV16 IgG and neutralizing antibodies seem to be serological markers for latent or past infections.

Groundwater Leaching Potential of Pesticides: A Historic Review and Critical Analysis.

We evaluated the main leaching indices that have been used for decades for the protection of groundwater against contamination by pesticides. We describe the index classifications in detail and discuss their advantages and limitations relative to their prediction value. Most of the indices have similarities in the types of parameters they use. Some of the similarities are basic physicochemical properties of the pesticides such as their water solubility and their organic carbon partition coefficient, as well as characteristics such as environmental persistence in the soil and some soil characteristics. It is very difficult to maintain a simple index with high predictive power. However, comparisons are allowed by many indices among different active ingredients before pesticides are classified according to the risk of being groundwater contaminants. In contrast, limitations are the scarce inclusion of pesticide byproducts in the ground, lack of prediction capacity for polar pesticides, and lack of prediction of the vulnerability of groundwater to being contaminated by pesticides. Despite the limitations of such approaches, they are of great utility, particularly for protection of groundwater from pesticide contamination when little information is available, which is the case in most developing countries and in countries with economies in transition. Caution is recommended in the analysis of information generated by these approximations, which ideally should be validated experimentally in the different application scenarios and the needs for pesticide assessment based on local information. Environ Toxicol Chem 2024;00:1-14. © 2024 SETAC.

Persistence of vaccine origin Salmonella Typhimurium through the poultry production continuum, and development of a rapid typing scheme for their differentiation from wild type field isolates.

Salmonella enterica serovar Typhimurium is one of the top Salmonella serovars annually linked to poultry production and corresponding human illnesses. Because of this, vaccination of commercial poultry against Salmonella Typhimurium has been a focal point in recent years. There are several commercially available Salmonella Typhimurium vaccines available for use in poultry production. Among these are modified live vaccines, including Poulvac ST (Zoetis), Megan Egg (AviPro), and Megan Vac 1 (AviPro). In this study, analyses of 27 field isolates of Salmonella Typhimurium from poultry sources indicated evidence for the persistence of some vaccine-origin strains through the commercial production cycle. Further analyses of 26,812 database isolates indicated vaccine-origin isolates are persisting frequently through processing, are present on retail meat products, and are even occasionally found in human patients. A novel polymerase chain reaction (PCR) was created and validated which enables simultaneous identification of Salmonella enterica sp., the Salmonella Typhimurium serovar, and differentiation of wild type Salmonella Typhimurium from live attenuated vaccines involving mutations in the cya/crp or aroA genes. The PCR was developed considering whole genome differences between the vaccines and wild type field isolates and was validated using different field isolates and recovered vaccine strains. This method enables poultry producers to rapidly determine if recovered field isolates have a vaccine origin.

Spillover effects of reminder nudges in complex environments.

We present an experiment on the immediate and lasting effects of reminder nudges in a complex environment. In the study, 1,542 subjects face a setting where, within a brief time frame, they have to pay attention to and perform multiple actions in a computer game. The experiment investigates i) the effect of reminders on the reminded actions and their spillovers on nonreminded actions; ii) spillovers between multiple nudges when the number of reminded actions is increased; and iii) intertemporal spillovers from having been exposed to reminders on actions after reminders are withdrawn. Our findings reveal, first, that reminders have a positive effect on the overall number of actions performed. It results from the positive direct effect on the reminded actions dominating the negative spillovers on nonreminded actions. These negative effects are notable in our setting, where reminders could potentially have positive spillovers by freezing attention or by indirectly prompting actions similar to the reminded ones. Second, we observe that reminder nudges are scalable. Increasing the number of reminded actions leads subjects to take more actions overall, albeit with diminishing returns and more pronounced negative spillover effects. Third, after reminders are withdrawn, the positive effect on reminded actions diminishes, while negative spillovers on nonreminded actions persist, thus rendering reminders ineffective in increasing the overall number of actions performed.

Positive correlation between persistence of medical nutrition therapy and overall survival in patients with head and neck cancer.

Background: Several factors can affect overall survival of head and neck cancer (HNC) patients, including characteristics of the cancer disease and response to treatments. However, patients' nutritional status and the effectiveness of medical nutrition therapy (MNT) can also impact overall survival. The primary goal of our research was to collect real-life data on the use of MNT in HNC patients and to specifically investigate the correlation between survival and the duration of uninterrupted (persistent) nutrition. Method: The data of this retrospective, analytical, cohort study was collected from electronic healthcare records from the Hungarian National Health Insurance Fund Management. Overall, 38,675 HNC patients' data of the period between 2012 and 2021 was used. We applied multi-step exclusions to identify patient groups accurately and to avoid biasing factors. Statistical analysis was done by the Kaplan-Meier method, log-rank test, and Cox regression analysis. Results: Throughout the investigated period 16,871 (64%) patients received MNT therapy out of 26,253 newly diagnosed patients (≥18 years). In terms of the persistence of MNT, we divided the patients into three groups (1-3; 4-6; ≥7-month duration of MNT). When comparing these groups, we found that patients receiving long-term (≥7 months) MNT had a significantly longer overall survival (p < 0.0001) than those who received MNT for a shorter duration, both in locally advanced and recurrent/metastatic cases. Conclusion: The main outcome of the study is that there is a positive correlation between the persistence of MNT and the overall survival in HNC patients when nutritional intervention lasts several months. It highlights the responsibility of the specialists during the patient journey to use MNT early and to continue its use for as long as it is beneficial to the patients.

Sortase-encoding genes, srtA and srtC, mediate Enterococcus faecalis OG1RF persistence in the Helicoverpa zea gastrointestinal tract.

Enterococcus faecalis is a commensal and opportunistic pathogen in the gastrointestinal (GI) tract of mammals and insects. To investigate mechanisms of bacterial persistence in the gastrointestinal tract (GIT), we developed a non-destructive sampling model using Helicoverpa zea, a destructive agricultural pest, as host to study the role of bacterial sortase enzymes in mitigating persistence in the gastrointestinal tract. E. faecalis OG1RF ΔsrtA and E. faecalis OG1RF ΔsrtC, isogenic E. faecalis OG1RF sortase mutants grew similarly under planktonic growth conditions relative to a streptomycin-resistant E. faecalis OG1RFS WT in vitro but displayed impaired biofilm formation under, both, physiological and alkaline conditions. In the H. zea GI model, both mutants displayed impaired persistence relative to the WT. This represents one of the initial reports in which a non-destructive insect model has been used to characterize mechanisms of bacterial persistence in the Lepidopteran midgut and, furthermore, sheds light on new molecular mechanisms employed by diverse microorganisms to associate with invertebrate hosts.

Evolution of exploitation and replication of giant viruses and virophages.

Tripartite biotic interactions are inherently complex, and the strong interdependence of species and often one-sided exploitation can make these systems vulnerable to extinction. The persistence of species depends then on the balance between exploitation and avoidance of exploitation beyond the point where sustainable resource use is no longer possible. We used this general prediction to test the potential role of trait evolution for persistence in a tripartite microbial system consisting of a marine heterotrophic flagellate preyed upon by a giant virus, which in turn is parasitized by a virophage. Host and virophage may benefit from this interaction because the virophage reduces the harmful effects of the giant virus on the host population and the virophage can persist integrated into the host genome when giant viruses are scarce. We grew hosts and virus in the presence and absence of the virophage over ∼280 host generations and tested whether levels of exploitation and replication in the giant virus and/or virophage population evolved over the course of the experiment, and whether the changes were such that they could avoid overexploitation and extinction. We found that the giant virus evolved toward lower levels of replication and the virophage evolved toward increased replication but decreased exploitation of the giant virus. These changes reduced overall host exploitation by the virus and virus exploitation by the virophage and are predicted to facilitate persistence.

Differential impacts of DNA repair machinery on fluoroquinolone persisters with different chromosome abundances.

DNA repair machinery has been found to be indispensable for fluoroquinolone (FQ) persistence of Escherichia coli. Previously, we found that cells harboring two copies of the chromosome (2Chr) in stationary-phase cultures were more likely to yield FQ persisters than those with one copy of the chromosome (1Chr). Furthermore, we found that RecA and RecB were required to observe that difference, and that loss of either more significantly impacted 2Chr persisters than 1Chr persisters. To better understand the survival mechanisms of persisters with different chromosome abundances, we examined their dependencies on different DNA repair proteins. Here, we show that lexA3 and ∆recN negatively impact the abundances of 2Chr persisters to FQs, without significant impacts on 1Chr persisters. In comparison, ∆xseA, ∆xseB, and ∆uvrD preferentially depress 1Chr persistence to levels that were near the limit of detection. Collectively, these data show that the DNA repair mechanisms used by persisters vary based on chromosome number, and suggest that efforts to eradicate FQ persisters will likely have to take heterogeneity in single-cell chromosome abundance into consideration. IMPORTANCE: Persisters are rare phenotypic variants in isogenic populations that survive antibiotic treatments that kill the other cells present. Evidence has accumulated that supports a role for persisters in chronic and recurrent infections. Here, we explore how an under-appreciated phenotypic variable, chromosome copy number (#Chr), influences the DNA repair systems persisters use to survive fluoroquinolone treatments. We found that #Chr significantly biases the DNA repair systems used by persisters, which suggests that #Chr heterogeneity should be considered when devising strategies to eradicate these troublesome bacterial variants.

Cultural persistence and the 'herbal medicine paradox': Evidence from European data.

The use of herbal or traditional medicines has survived the proliferation of modern medicine. The phenomenon has been labeled as the 'herbal medicines paradox' (HMP). We study whether such HMP hypothesis can be explained by the persistence of attitudes across cultural boundaries. We undertake a secondary analysis of individual-level migration data to test the persistence of the use of herbal medicines in relation to norms in the person's country of birth (or home country). We study the association between attitudes towards herbal medicine treatments of both first (N = 3630) and second-generation (N = 1618) immigrants in 30 European countries, and the average attitudes of their sending country origins. We find robust evidence of an association that is stronger for the second-generation migrants. We document a stronger effect among maternal than paternal lineages, as well as significant heterogeneity based on migrants' country of origin. Our estimates are robust to different sample analysis. Our estimates are consistent with a cultural explanation for the HMP.

Real-world persistence of multiple sclerosis disease-modifying therapies.

BACKGROUND AND PURPOSE: Treatment persistence is the continuation of therapy over time. It reflects a combination of treatment efficacy and tolerability. We aimed to describe real-world rates of persistence on disease-modifying therapies (DMTs) for people with multiple sclerosis (pwMS) and reasons for DMT discontinuation. METHODS: Treatment data on 4366 consecutive people with relapse-onset multiple sclerosis (MS) were pooled from 13 UK specialist centres during 2021. Inclusion criteria were exposure to at least one MS DMT and a complete history of DMT prescribing. PwMS in blinded clinical trials were excluded. Data collected included sex, age at MS onset, age at DMT initiation, DMT treatment dates, and reasons for stopping or switching DMT. For pwMS who had received immune reconstituting therapies (cladribine/alemtuzumab), discontinuation date was defined as starting an alternative DMT. Kaplan-Meier survival analyses were used to express DMT persistence. RESULTS: In 6997 treatment events (1.6 per person with MS), median time spent on any single maintenance DMT was 4.3 years (95% confidence interval = 4.1-4.5 years). The commonest overall reasons for DMT discontinuation were adverse events (35.0%) and lack of efficacy (30.3%). After 10 years, 20% of people treated with alemtuzumab had received another subsequent DMT, compared to 82% of people treated with interferon or glatiramer acetate. CONCLUSIONS: Immune reconstituting DMTs may have the highest potential to offer a single treatment for relapsing MS. Comparative data on DMT persistence and reasons for discontinuation are valuable to inform treatment decisions and in personalizing treatment in MS.

Defective viral genomes: advances in understanding their generation, function, and impact on infection outcomes.

Defective viral genomes (DVGs) are truncated derivatives of their parental viral genomes generated during an aberrant round of viral genomic replication. Distinct classes of DVGs have been identified in most families of both positive- and negative-sense RNA viruses. Importantly, DVGs have been detected in clinical samples from virally infected individuals and an emerging body of association studies implicates DVGs in shaping the severity of disease caused by viral infections in humans. Consequently, there is growing interest in understanding the molecular mechanisms of de novo DVG generation, how DVGs interact with the innate immune system, and harnessing DVGs as novel therapeutics and vaccine adjuvants to attenuate viral pathogenesis. This minireview focuses on single-stranded RNA viruses (excluding retroviridae), and summarizes the current knowledge of DVG generation, the functions and diversity of DVG species, the roles DVGs play in influencing disease progression, and their application as antivirals and vaccine adjuvants.

Parthenogenetic stick insects exhibit signatures of preservation in the molecular architecture of male reproduction.

After the loss of a trait, theory predicts that the molecular machinery underlying its phenotypic expression should decay. Yet, empirical evidence is contrasting. Here, we test the hypotheses that (1) the molecular ground plan of a lost trait could persist due to pleiotropic effects on other traits and (2) that gene co-expression network architecture could constrain individual gene expression. Our testing ground has been the Bacillus stick insect species complex, which contains close relatives that are either bisexual or parthenogenetic. After the identification of genes expressed in male reproductive tissues in a bisexual species, we investigated their gene co-expression network structure in two parthenogenetic species. We found that gene co-expression within the male gonads was partially preserved in parthenogens. Furthermore, parthenogens did not show relaxed selection on genes upregulated in male gonads in the bisexual species. As these genes were mostly expressed in female gonads, this preservation could be driven by pleiotropic interactions and an ongoing role in female reproduction. Connectivity within the network also played a key role, with highly connected - and more pleiotropic - genes within male gonad also having a gonad-biased expression in parthenogens. Our findings provide novel insight into the mechanisms which could underlie the production of rare males in parthenogenetic lineages; more generally, they provide an example of the cryptic persistence of a lost trait molecular architecture, driven by gene pleiotropy on other traits and within their co-expression network.

Indirect CD4+ T cell protection against mouse gamma-herpesvirus infection via interferon gamma.

CD4+ T cells play a key role in γ-herpesvirus infection control. However, the mechanisms involved are unclear. Murine herpesvirus type 4 (MuHV-4) allows relevant immune pathways to be dissected experimentally in mice. In the lungs, it colonizes myeloid cells, which can express MHC class II (MHCII), and type 1 alveolar epithelial cells (AEC1), which lack it. Nevertheless, CD4+ T cells can control AEC1 infection, and this control depends on MHCII expression in myeloid cells. Interferon-gamma (IFNγ) is a major component of CD4+ T cell-dependent MuHV-4 control. Here, we show that the action of IFNγ is also indirect, as CD4+ T cell-mediated control of AEC1 infection depended on IFNγ receptor (IFNγR1) expression in CD11c+ cells. Indirect control also depended on natural killer (NK) cells. Together, the data suggest that the activation of MHCII+ CD11c+ antigen-presenting cells is key to the CD4+ T cell/NK cell protection axis. By contrast, CD8+ T cell control of AEC1 infection appeared to operate independently. IMPORTANCE: CD4+ T cells are critical for the control of gamma-herpesvirus infection; they act indirectly, by recruiting natural killer (NK) cells to attack infected target cells. Here, we report that the CD4+ T cell/NK cell axis of gamma-herpesvirus control requires interferon-γ engagement of CD11c+ dendritic cells. This mechanism of CD4+ T cell control releases the need for the direct engagement of CD4+ T cells with virus-infected cells and may be a common strategy for host control of immune-evasive pathogens.