Herd Immunity Research Articles

Coordinated immune dysregulation in Juvenile Dermatomyositis revealed by single-cell genomics.

Juvenile Dermatomyositis (JDM) is one of several childhood-onset autoimmune disorders characterized by a type I interferon response and autoantibodies. Treatment options are limited due to incomplete understanding of how the disease emerges from dysregulated cell states across the immune system. We therefore investigated the blood of JDM patients at different stages of disease activity using single-cell transcriptomics paired with surface protein expression. By immunophenotyping peripheral blood mononuclear cells, we observed skewing of the B cell compartment towards an immature naive state as a hallmark of JDM at diagnosis. Furthermore, we find that these changes in B cells are paralleled by T cell signatures suggestive of Th2-mediated inflammation that persist despite disease quiescence. We applied network analysis to reveal that hyperactivation of the type I interferon response in all immune populations is coordinated with previously masked cell states including dysfunctional protein processing in CD4+ T cells and regulation of cell death programming in NK, CD8+ T cells and gdT cells. Together, these findings unveil the coordinated immune dysregulation underpinning JDM and provide insight into strategies for restoring balance in immune function.

Investigating the trend of demographic changes, mortality, clinical and paraclinical findings of patients hospitalized in the Corona ward, before and after the start of general vaccination of COVID-19

BackgroundPrioritizing prevention over treatment has been a longstanding principle in the world health system. This study aims to compare the demographic changes, mortality, clinical, and paraclinical findings of patients hospitalized in the Corona ward before and after the start of general vaccination.MethodsThis cross-sectional study utilized the simple random sampling method in 2022, analyzing 300 medical records of patients admitted to the Corona ward at 22 Bahman Khaf Hospital. Data were collected using a checklist with the help of the Medical Care Monitoring System and analyzed using SPSS-22 statistical software and Chi-square statistical test at a significance level of p < 0.05.ResultsBefore the start of general vaccination for COVID-19, the majority of patients were hospitalized in the Corona Intensive Care Unit (59.3%), aged between 51 and 65 years (47.3%), hospitalized for more than 3 days (54%), required intubation (49.3%), had SPO2 < 93% (60.7%), and exhibited common symptoms such as cough, shortness of breath, and loss of consciousness. Paraclinical findings included positive CRP, decreased lymphocytes, and ground glass opacity (GGO). After the start of general vaccination for COVID-19, most patients were hospitalized in the general care department of Corona (68%), aged between 36 and 50 years (47.3%), hospitalized for less than three days (66%), required intubation (20%), had SPO2 ≥ 93% (77.3%), and exhibited common symptoms such as weakness, headache, and body pain. Paraclinical findings were within the normal range.ConclusionsGeneral vaccination for COVID-19 has significantly reduced patient mortality and morbidity. Health policymakers should prioritize general vaccination to achieve herd immunity and improve public health.

Questionable Immunity to Mumps among Healthcare Workers in Italy—A Cross-Sectional Serological Study

Highly contagious diseases, such as mumps, are a global concern as new epidemics continue to emerge, even in highly vaccinated populations. The risk of transmission and spread of these viruses is even higher for individuals who are more likely to be exposed, including healthcare workers (HCWs). In healthcare settings, both HCWs and patients are at risk of infection during the care process, potentially leading to nosocomial epidemic outbreaks. Mumps is often underestimated compared with measles and rubella, despite being milder and less likely to spread. In fact, the risk of complications following mumps infection is extremely high, especially if the disease occurs in adulthood. The measles–mumps–rubella (MMR) vaccine has been shown to be an excellent preventive measure. Unfortunately, the mumps component appears to be less effective in inducing immunity than those for measles and rubella (two-dose effectiveness of 85%, 95% and 97%, respectively). The main aim of our study was to investigate the prevalence of detectable mumps antibodies (serum IgG antibodies) in a cohort of Italian and foreign HCWs in relation to personal and occupational factors. We included in the study 468 subjects who underwent health surveillance at the Occupational Medicine Unit of the Tor Vergata Polyclinic in Rome during the period from January 2021 to March 2023. In our study, the proportion of HCWs found to be unprotected against mumps was very high (8.3%), and those found to be immune are below the WHO threshold for herd immunity (95%). From our data, it seems essential that all occupational health services carry out an accurate screening with a dose of anti-mumps antibodies to assess serological protection before starting a job, regardless of an individual’s vaccination history. This approach is proving to be beneficial, accurate, as it allows all serologically non-immune individuals to be vaccinated in the workplace, including those who would be protected by their vaccination history but have lost the antibody response.

Social and Structural Determinants of Health Associated with COVID-19 Vaccine Hesitancy among Older Adults in the United States

State-level COVID-19 vaccination rates among older adults have been uneven in the United States. Due to the immunocompromised nature of older adults, vaccine hesitancy increases the risk of morbidity and mortality. This study aims to determine the association between the social determinants of health, the structural determinants of health, and COVID-19 vaccine hesitancy among older adults in the United States. Secondary data from the Health and Retirement Study (HRS) dataset were used. A descriptive analysis and multinomial multivariable logistic regression were performed to examine the association of the independent variables—gender, age, race, immigration status, marital status, broadband internet access, social security income, Medicare coverage, education, and frequency of religious service—with the dependent variable, vaccine hesitancy. Compared to the respondents with no vaccine hesitancy and without the specific predictor, the respondents who reported religious attendance at least once/week were more likely to be “somewhat hesitant”, divorced respondents had higher odds of being “somewhat hesitant”, and older adults aged 65–74 years were more likely to be “very hesitant” or “somewhat hesitant” about the COVID-19 vaccine. Compared to the respondents with no vaccine hesitancy and without the specific predictor, females had higher odds of being “very hesitant”, “somewhat hesitant”, or a “little hesitant”, and African Americans were more likely to be “very hesitant”, “somewhat hesitant”, or a “little hesitant” about the COVID-19 vaccine. Addressing these factors may limit the barriers to vaccine uptake reported among older adults and improve herd immunity among the immunocompromised population.

Sequence analysis of respiratory syncytial virus cases reveals a novel subgroup -B strain circulating in north-central Italy after pandemic restrictions

BackgroundFollowing the pandemic restrictions, the epidemiology of respiratory syncytial virus (RSV) has changed, leading to intense hospitalization peaks. ObjectivesThis study, conducted at multiple sites in Italy, aimed to describe the temporal dynamics of two post-COVID-19 RSV epidemics. Additionally, the circulating RSV-A and -B lineages were characterized and compared to those found in 2018 and 2019. Study designRespiratory specimens and data were collected from RSV-positive patients, both inpatients, and outpatients, of all ages at three sites in north-central Italy. To analyze these samples, roughly one-sixth were sequenced in the attachment glycoprotein G gene and subjected to phylogenetic and mutational analyses, including pre-pandemic sequences from north-central Italy. ResultsThe first post-pandemic surge of RSV cases was quite intense, occurring from October 2021 to early January 2022. The subsequent RSV epidemic (from November 2022 to early March 2023) also had a high impact, characterized by a rise in elderly patient cases. Post-pandemic cases of RSV-A were caused by various strains present in Italy prior to COVID-19. In contrast, a distinct RSV-B lineage, which was concurrently spreading in other countries, was identified as the main cause of the surge in 2022–2023 but remained undetected in Italy before the pandemic. ConclusionsThis study describes the temporal dynamics of post-pandemic RSV subgroups and uncovers a lineage of RSV-B with high genetic divergence that may have increased the impact of decreased population immunity.

Parvovirus B19 infection: characteristics of population immunity in the world

Parvovirus B19 infection (PVI) is one of the relatively new problems in infectology, data on the study of its prevalence in our country began to appear only at the beginning of the twenty-first century. The article presents the results of an analysis of studies from available literature sources highlighting the prevalence of PVI markers at the population level among different social groups of the population at the present stage. The clinical manifestations of PVI are diverse, which requires differential diagnosis, both with exanthemic infectious diseases and with non-infectious pathology. Due to the peculiarity of PVI pathogenesis, it is relevant for various socially significant populations, primarily patients with exanthemic manifestations of various diseases, persons from among blood donors, pregnant women and women planning pregnancy. Furthermore, unlike most countries, our country does not have a system for PVI detecting and reporting in the system of state sanitary and epidemiological supervision, which makes it difficult to conduct research on this topic.

Immunity against measles, mumps, rubella, and varicella among homeless individuals in Germany — A nationwide multi-center cross-sectional study

IntroductionHomeless individuals suffer a high burden of vaccine-preventable infectious diseases. Moreover, they are particularly susceptible to adverse infection outcomes with limited access to the health care system. Data on the seroprevalence of measles, mumps, rubella, and varicella within this cohort are missing.MethodsThe seroprevalence of measles, mumps, rubella, and varicella was determined within the homeless population in Germany. Predictors of lacking immune protection were determined using multivariable logistic regression analysis.ResultsHomeless individuals in Germany (n = 611) showed a seroprevalence of 88.5% (95% CI: 85.8–91.0) for measles, 83.8% (95% CI: 80.6–86.6) for mumps, 86.1% (95% CI: 83.1–88.7) for rubella, and 95.7% (95% CI 93.8–97.2) for varicella. Measles seroprevalences declined from individuals born in 1965 to individuals born in 1993, with seroprevalences not compatible with a 95% threshold in individuals born after 1980. For mumps, seroprevalences declined from individuals born in 1950 to individuals born in 1984. Here, seroprevalences were not compatible with a 92% threshold for individuals born after 1975. Seronegativity for measles, mumps and rubella was associated with age but not with gender or country of origin.DiscussionHerd immunity for measles and mumps is not achieved in this homeless cohort, while there was sufficient immune protection for rubella and varicella. Declining immune protection rates in younger individuals warrant immunization campaigns also targeting marginalized groups such as homeless individuals. Given that herd immunity thresholds are not reached for individuals born after 1980 for measles, and after 1975 for mumps, vaccination campaigns should prioritize individuals within these age groups.

A nomogram to predict mortality in patients with severe fever with thrombocytopenia syndrome

Severe fever with thrombocytopenia syndrome (SFTS) is an acute infectious disease caused by a novel Bunyavirus infection with low population immunity and high mortality rate. Lacking specific therapies, the treatment measures vary with the severity of the disease, therefore, a case control study involved 394 SFTS patients was taken to determine risk factors for mortality. Comparative clinical data from the first 24 h after admission was collected through the electronic medical record system. Independent risk factors for death of SFTS were identified through univariate and multivariate binary logistic regression analyses. The results of the logistic regression were visualized using a nomogram which was created by downloading RMS package in the R program. In our study, four independent mortality risk factors were identified: advanced age(mean 70.45 ± 7.76 years), MODS, elevated APTT, and D-dimer. The AUC of the nomogram was 0.873 (0.832, 0.915), and the model passes the calibration test namely Unreliability test with P = 0.958, showing that the model's predictive ability is excellent. The nomogram to determine the risk of death in SFTS efficiently provide a basis for clinical decision-making for treatment.

Molecular landscape and clinical implication of CCNE1-amplified esophagogastric cancer.

Cyclin E overexpression as a result of CCNE1 amplification is a critical driver of genomic instability in gastric cancer, but its clinical implication is largely unknown. Thus, we integrated genomic, transcriptomic, and immune profiling analysis of 7,083 esophagogastric tumors and investigated the impact of CCNE1 amplification on molecular features and treatment outcomes. We identified CCNE1 amplification in 6.2% of esophageal adenocarcinoma samples, 7.0% of esophagogastric junction carcinoma, 4.2% of gastric adenocarcinoma samples, and 0.8% of esophageal squamous cell carcinoma. Metastatic sites such as lymph node and liver showed an increased frequency of CCNE1 amplification relative to primary tumors. Consistent with a chromosomal instability phenotype, CCNE1 amplification was associated with decreased CDH1 mutation and increased TP53 mutation and ERBB2 amplification. We observed no differences in immune biomarkers such as PD-L1 expression and tumor mutational burden comparing CCNE1-amplified and non-amplified tumors, although CCNE1 amplification was associated with changes in immune populations such as decreased B cells and increased M1 macrophages from transcriptional analysis. Real-world survival analysis demonstrated that patients with CCNE1-amplified gastric cancer had worse survival after trastuzumab for HER2-positive tumors, but better survival after immunotherapy. These data suggest that CCNE1-amplified gastric cancer has a distinct molecular and immune profile with important therapeutic implications, and therefore further investigation of CCNE1 amplification as a predictive biomarker is warranted.

3 The impact of early-life cecal microbiota transplantation on injurious behaviors in egg-laying chickens

Abstract Injurious behaviors in laying hens are a critical issue facing the poultry egg industry. Recent studies have shown that the gut microbiota influences host brain function and behavioral characteristics in humans and various animals. In laying hens, it has been reported that injurious behaviors (such as aggression, feather pecking and cannibalism) are associated with dysregulation of the microbiota-gut-brain axis. To further interrogate the role of the microbiota-gut-brain axis on bird behavior, we used two inbred layer chicken lines, 63 and 72 (line 72 displays more aggressive behavior), and transferred pooled cecal contents from either line to day of hatch chicks. Cecal microbiota transplantation (CMT) from each line was conducted once daily, by gavage, from d 1 to 10, then boosted once weekly from wk 3 to 5. We hypothesized that the cecal microbiota composition and animal behavior in recipient birds would be similar to that of their donor animals because of the microbiota-gut-brain axis. Microbial communities were compared using 16S rRNA gene amplicon sequencing, behavior was recorded in home cages as well as in paired aggression tests, and physiological measurements were taken from brain tissue and blood to measure levels of neurotransmitters and immune function. When examining the differences in the donor birds, hypothalamic serotonin and tryptophan concentrations were greater for line 63 compared with line 72 birds (P &amp;lt; 0.05). Plasma corticosterone, heterophil/lymphocyte ratios, and central norepinephrine concentrations were less for line 63 birds (P &amp;lt; 0.05). Cecal microbial diversity was not statistically different between the lines, but many bacterial taxa were differentially abundant between the two lines. After cecal transplantation, 63-CMT (recipient) birds displayed less aggressive behavior with a greater hypothalamic serotonergic activity at wk 5, similar to donor birds. Correspondingly, two amplicon sequence variants (ASVs) belonging to Lachnospiraceae and one Ruminococcaceae UCG-005 ASV were positively correlated with the concentrations of brain tryptophan and serotonin, respectively. Along with greater aggression, 72-CMT birds seemed to have greater physical growth traits (increased body weight, ileal villus/crypt; P ≤ 0.05), but decreased concentrations of brain norepinephrine and dopamine, and the greatest ileal serotonin turnover in the ileum at wk 5 (P &amp;lt; 0.05). ASVs belonging to Mollicutes RF39 and GCA-900066225 in 72-CMT birds were negatively correlated with the brain 5-hydroxyindoleacetic acid (5-HIAA) at wk 5, and one Bacteroides ASV was negatively correlated with plasma serotonin at wk 16. Meanwhile, 63-CMT birds potentially had better gut health and immune function (greater concentrations of ileal mucosal secretory IgA, plasma IL-10; P &amp;lt; 0.05). These results suggest linkages among serotonergic activity, stress response, innate immunity, and gut microbiota populations and that CMT could be a novel strategy for reducing aggressive behavior through regulating signaling along the microbiota-gut-brain axis.

Development of a real-time fluorescent reverse transcription loop-mediated isothermal amplification assay with quenching primers for rapid detection of rubella virus

Rubella virus infection during early pregnancy sometimes causes severe birth defects termed congenital rubella syndrome. Although there are safe and effective live-attenuated vaccines, rubella has only been certified as eliminated in the Americas within the six World Health Organization regions. Rubella remains an endemic disease in many regions, and outbreaks occur wherever population immunity is insufficient. There are two main methods for diagnosis of rubella: detection of anti-rubella IgM antibodies by enzyme immunoassay and detection of the viral genome by real-time RT-PCR. Both of these methods require substantial time and effort. In the present study, a rapid rubella detection assay using real-time fluorescent reverse transcription loop-mediated isothermal amplification with quenching primers was developed. The time required for the new assay was one-half that required for a real-time RT-PCR assay. The assay had 93.6% positive percent agreement and 100% negative percent agreement for clinical specimens compared with the real-time RT-PCR assay. The new assay is considered useful for diagnosis of rubella in areas where rubella is endemic.

The role of hematopoiesis in bone repair: an update

Purpose of review The repair of bone after injury requires the participation of many different immune cell populations, which are derived from the hematopoietic lineage. The field of osteoimmunology, or the study of the interactions between bone and the immune system, is a growing field with emerging impact on both the basic science and clinical aspects of fracture healing. Recent findings Despite previous focus on the innate immune system in fracture healing, recent studies have revealed an important role for the adaptive immune system in bone repair. The composition of adaptive and innate immune cell populations present at the fracture site is significantly altered during aging and diet-induced obesity, which may contribute to delayed healing. Recent data also suggest a complicated relationship between fracture repair and systemic inflammation, raising the possibility that immune populations from distant sites such as the gut can impact the bone repair process. Summary These findings have important implications for the treatment of fracture patients with antibiotics or anti-inflammatory drugs. Furthermore, the effects of systemic inflammation on fracture repair in the contexts of aging or obesity should be carefully interpreted, as they may not be uniformly detrimental.

Abstract PO4-14-07: Genomic and immune profiling of breast cancer brain metastases

Abstract BACKGROUND: Brain metastases (BrM) arising from breast cancer (BC) are an increasing consequence of advanced disease, with up to half of patients (pts) with metastatic HER2+ or triple negative breast cancer experiencing central nervous system (CNS) recurrence. The genomic alterations driving CNS recurrence, along with contribution of the immune microenvironment, particularly by BC subtype remains unclear. METHODS: We characterized BrM from a cohort of n=42 BC pts by sequencing whole-exome DNA and total RNA libraries from frozen (n=31) and FFPE (n=34) BCBrM, FFPE extracranial (ECT, n=12) and blood DNA (n=26) tissues from the Duke Brain Tumor Biorepository. Analyses conducted and planned include inference of PAM50 intrinsic subtypes, somatic mutations, copy number alterations, immune cell type decompositions by CIBERSORTx, differential RNA expression, driver analysis, and associations with clinical outcomes. RESULTS: PAM50 subtypes across 31 frozen BrM were 23% Luminal (Lum) A, 13% LumB, 33% HER2-enriched, 27% Basal-like, 3% Normal-like. For 34 FFPE BrM, 15% were LumA, 24% LumB, 33% HER2-enriched, 24% Basal-like, 3% Normal-like. Across 26 paired FFPE and frozen BrM, subtype discrepancy was seen in 23% (6) cases of which frozen to FFPE classification differed: 3 LumA to LumB, 1 LumB to LumA, 1 Normal to LumB, and 1 Basal to LumB. Among 10 paired FFPE BrM and ECT, subtype concordance was observed in 70%. Discordance was seen in 1 case each for ECT to BrM: LumB to HER2, LumB to LumA, Basal to Normal-like. WES demonstrated frequent copy number alterations (CNA) in clinically-relevant genes including TGFB1, NOTCH1, CDK4, and ERBB3, in both BrM and ECT. For pts with matched blood, ERBB3 CNA (gain and loss) were more commonly found in FFPE BrM (7/19, 37%) compared to ECT (1/8, 13%). Among BrM, the most frequently altered clinically-relevant genes included TP53 (~75%), PTEN, EGFR, RB1, PIK3CA, NF1 and ESR1 (all ≤15%); in ECT, TP53 (67%), BRCA2, FBXW7, and ATM (all ≤33%). PI3K pathway genes (e.g. PTEN, PIK3CA) alterations were exclusive to BrM. One pt’s ECT showed an ATM mutation that was not observed in the paired BrM. Conversely, BRAF and CCND2 mutations were observed in BrM, but not ECT for 1 pt each. Inferring the relative abundance of immune populations in frozen BrM illustrated that 23% were CD4+ resting memory T cells, 25% M2 tumor-permissive macrophages, 13% M0 macrophages; M1 tumor-inhibiting macrophages were only 2%. When comparing immune cell populations between FFPE BrM and ECT, ECT had more M1 macrophages (Chi-sq 4.23, P = 0.04), while other immune cell populations were of similar relative abundance. Immune cell fractions did not vary by subtype in BrM or ECT with one exception: M2 macrophages were lower in Basal compared to LumB tissues (frozen BrM: Chi-sq = 9.28, P = 0.05; FFPE BrM: Chi-sq = 4.61, P = 0.33; FFPE EC: Chi-sq = 9.78, P = 0.04). In n=8 pt-matched FFPE BrM/ECT, hallmark pathways upregulated in BrM included MYC and E2F targets and oxidative phosphorylation, while those with lower expression in BrM included epithelial-mesenchymal transition, interferon gamma response, and JAK-STAT signaling. CONCLUSION: This analysis showed moderate discrepancy in subtype call of BrM by tissue preparation (frozen vs. FFPE), with LumB classification showing the highest discrepancy, and more commonly called in FFPE tissues. Subtype concordance between ECT and BrM was relatively high. Analysis of CNA illustrated deletions and amplifications in targetable genes, notably ERBB3 preferentially in BrM compared to ECT. Mutational analysis identified targetable alterations exclusive to BrM; this knowledge could lead to BrM-targeted treatments. Inferred immune cell populations illustrated a tumor permissive microenvironment in BrM. Therapeutic strategies repolarizing macrophages toward a tumor-inhibiting phenotype in BrM are warranted. Analyses of associations between genomic data and clinical outcomes, as well as driver analyses, are ongoing. Citation Format: Amanda Van Swearingen, Marissa Lee, Layne Rogers, Alexander Sibley, Pixu Shi, Xiaodi Qin, Michael Goodin, Kouros Owzar, Carey Anders. Genomic and immune profiling of breast cancer brain metastases [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-14-07.

Abstract PO2-25-03: Deciphering the immune molecular signature associated with pembrolizumab efficacy in the neoadjuvant setting of Triple-Negative Breast Cancer patients: a single-centre experience

Abstract Triple-negative breast cancer (TNBC) accounts for 15-20% of all breast cancers and is characterized by a high rate of recurrence, despite the improvement of the therapeutic approaches in recent years. Neoadjuvant chemotherapy (NACT) is the standard treatment for early-stage TNBC. Achieving a pathological complete response (pCR) is considered an essential prognostic factor for long-term outcomes. However, the percentage of pCR patients after NACT is limited to 30-40%, thus requiring the implementation of novel therapeutic strategies. Recently, by applying a morphology-guided spatial transcriptomic approach on Tru-Cut biopsies, we showed that intratumoral infiltrating lymphocytes (iTILs) and stromal Natural Killer (NK) cells are major determinants of chemotherapy efficacy in TNBC. These data highlight a complex three-dimensional organization of the tumor landscape and underline how spatiality and molecular activation of immune cells are essential to enhance the efficacy of neoadjuvant NACT in TNBC. The fact that immune cells are important players in this setting is corroborated by the clinical success shown by the KEYNOTE-522 study. This trial paved the way for the use of immunotherapy in neoadjuvant settings, obtaining a significant improvement in the patient’s overall response compared to standard NACT. Still, the implementation of chemotherapy with immunotherapy in the TNBC neoadjuvant treatment implicates several compelling questions, including how to further increase the percentage of patients with a complete response, overcoming resistance mechanisms, and how to improve the personalization of treatment, evaluating which patients can benefit from a therapy de-scalation or another combined therapeutic strategy. In this prospective cohort study, we decided to define the relevance of different immune populations in affecting pembrolizumab efficacy in the neoadjuvant treatment of TNBC patients. We treated 40 patients with an early-TNBC diagnosis with the KEYNOTE-522 regimen that consists of four cycles of an intravenous infusion of pembrolizumab plus paclitaxel and carboplatin, followed by four cycles of pembrolizumab plus epirubicin and cyclophosphamide. Only patients with evident side effects to immunotherapy administration were a priori excluded. Currently, 18 patients ended the neoadjuvant schedule and underwent surgical excision. Our data indicate that 15 patients displayed a pCR at the end of the therapy, whereas 3 patients displayed only partial response. To further clarify the immune dynamics that lead to a complete response to pembrolizumab in these patients, we collected peripheral blood before and after neoadjuvant treatment to isolate peripheral blood mononucleated cells (PBMCs). We applied a single-cell transcriptome analysis to shape any variations in circulating immune cells occurring during neoadjuvant treatment and associated with patient response. In addition, we collected residual tumors at surgery from partial responders and derived three-dimensional organoids that recapitulate the characteristics of the original patient tumor. These ex vivo organoid-based platforms are applied to clarify the molecular mechanisms driving neoadjuvant resistance. To this aim, we are performing co-cultures with autologous immune cells to identify novel combined therapeutic strategies to rescue pembrolizumab efficacy in these models. Overall, our study is defining the immune-related molecular mechanisms driving pembrolizumab and chemotherapy response in the neoadjuvant treatment of TNBC patients. Our findings can improve our understanding of which immune populations are determinant players in anti-TNBC immune response and can be proposed as novel biomarkers of pembrolizumab efficacy during the neoadjuvant treatment. Citation Format: Elisa Gasparini, Gloria Manzotti, Moira Ragazzi, Benedetta Donati, Federica Torricelli, Elisa Salviato, Alessandra Bisagni, Eleonora Zanetti, Alessandra Bologna, Saverio Coiro, Rita Vacondio, Guglielmo Ferrari, Giancarlo Bisagni, Carmine Pinto, Alessia Ciarrocchi, Francesca Reggiani. Deciphering the immune molecular signature associated with pembrolizumab efficacy in the neoadjuvant setting of Triple-Negative Breast Cancer patients: a single-centre experience [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-25-03.

Characterization of intestinal mononuclear phagocyte subsets in young ruminants at homeostasis and during Cryptosporidium parvum infection

IntroductionCryptosporidiosis is a poorly controlled zoonosis caused by an intestinal parasite, Cryptosporidium parvum, with a high prevalence in livestock (cattle, sheep, and goats). Young animals are particularly susceptible to this infection due to the immaturity of their intestinal immune system. In a neonatal mouse model, we previously demonstrated the importance of the innate immunity and particularly of type 1 conventional dendritic cells (cDC1) among mononuclear phagocytes (MPs) in controlling the acute phase of C. parvum infection. These immune populations are well described in mice and humans, but their fine characterization in the intestine of young ruminants remained to be further explored.MethodsImmune cells of the small intestinal Peyer’s patches and of the distal jejunum were isolated from naive lambs and calves at different ages. This was followed by their fine characterization by flow cytometry and transcriptomic analyses (q-RT-PCR and single cell RNAseq (lamb cells)). Newborn animals were infected with C. parvum, clinical signs and parasite burden were quantified, and isolated MP cells were characterized by flow cytometry in comparison with age matched control animals.ResultsHere, we identified one population of macrophages and three subsets of cDC (cDC1, cDC2, and a minor cDC subset with migratory properties) in the intestine of lamb and calf by phenotypic and targeted gene expression analyses. Unsupervised single-cell transcriptomic analysis confirmed the identification of these four intestinal MP subpopulations in lamb, while highlighting a deeper diversity of cell subsets among monocytic and dendritic cells. We demonstrated a weak proportion of cDC1 in the intestine of highly susceptible newborn lambs together with an increase of these cells within the first days of life and in response to the infection.DiscussionConsidering cDC1 importance for efficient parasite control in the mouse model, one may speculate that the cDC1/cDC2 ratio plays also a key role for the efficient control of C. parvum in young ruminants. In this study, we established the first fine characterization of intestinal MP subsets in young lambs and calves providing new insights for comparative immunology of the intestinal MP system across species and for future investigations on host–Cryptosporidium interactions in target species.

Multiplexed Imaging Mass Cytometry Analysis Characterizes the Vascular Niche in Pancreatic Cancer.

Oncogenesis and progression of pancreatic ductal adenocarcinoma (PDAC) is driven by complex interactions between the neoplastic component and the tumor microenvironment (TME), which includes immune, stromal, and parenchymal cells. In particular, most PDACs are characterized by a hypovascular and hypoxic environment that alters tumor cell behavior and limits the efficacy of chemotherapy and immunotherapy. Characterization of the spatial features of the vascular niche could advance our understanding of inter- and intra-tumoral heterogeneity in PDAC. Here, we investigated the vascular microenvironment of PDAC by applying imaging mass cytometry using a 26-antibody panel on 35 regions of interest (ROIs) across 9 patients, capturing over 140,000 single cells. The approach distinguished major cell types, including multiple populations of lymphoid and myeloid cells, endocrine cells, ductal cells, stromal cells, and endothelial cells. Evaluation of cellular neighborhoods identified 10 distinct spatial domains, including multiple immune and tumor-enriched environments as well as the vascular niche. Focused analysis revealed differential interactions between immune populations and the vasculature and identified distinct spatial domains wherein tumor cell proliferation occurs. Importantly, the vascular niche was closely associated with a population of CD44-expressing macrophages enriched for a pro-angiogenic gene signature. Together, this study provides insights into the spatial heterogeneity of PDAC and suggests a role for CD44-expressing macrophages in shaping the vascular niche.

Multi-level optimal energy management strategy for a grid tied microgrid considering uncertainty in weather conditions and load

Microgrids require efficient energy management systems to optimize the operation of microgrid sources and achieve economic efficiency. Bi-level energy management model is proposed in this paper to minimize the operational cost of a grid-tied microgrid under load variations and uncertainties in renewable sources while satisfying the various technical constraints. The first level is day ahead scheduling of generation units based on day ahead forecasting of renewable energy sources and load demand. In this paper, a recent meta-heuristic algorithm called Coronavirus Herd Immunity Optimizer (CHIO) is used to solve the problem of day-ahead scheduling of batteries, which is a complex constrained non-linear optimization problem, while the Lagrange multiplier method is used to determine the set-point of the Diesel Generator (DG). The second level of the proposed EMS is rescheduling and updating the set-points of sources in real-time according to the actual solar irradiance, wind speed, load, and grid tariff. In this paper, a novel real-time strategy is proposed to keep the economic operation during real-time under uncertainties. The obtained results show that the CHIO-based bi-level EMS demonstrates an optimal economic operation for a grid-connected microgrid in real-time when there are uncertainties in weather, utility tariffs, and load forecasts.

Epidemiological Aspects and Basic Directions of the Protective Medications against Monkeypox Development

Relevance. After smallpox eradication, in conditions of population immunity to orthopoxviruses absence, Monkeypox virus became most significant orthopoxvirus, pathogenic for humans. Therefore the generalization of data on the areas of infection outbreaks, human diseases and methods of prevention and treatment of monkey pox is important task. Aim. To characterize the problem of monkeypox in the world based on an analysis of foreign scientific publications over the past 20 years. Materials and methods. The work used publications presented in the main international medical information databases PubMed, Web of Science, Embase, etc. To analyze the publications, the analytical epidemiological method was used. Results and discussion. Monkeypox virus, obtained and identified in 1958, by genetic and phenotypic differences divides on two clades: West-African with lethality 3.6% and Central-African (Congo Basin) with lethality 10%. Monkeypox virus transmission to men happens in two ways, either from animal-to-human or human-to-human. Monkey pox is endemic only on African continent, but In 2003 year the first outbreak, numbering 47 confirmed cases, was occurred in non-endemic country – USA and the largest monkeypox outbreak began in Nigeria in September 2017 year and continue to the present. Comparison of the genome sequences of strains, isolated from patients in non-endemic countries, showed, that it genetically close to West-african strains, belong to II clades and were descended from a common ancestor. Many cases of disease in humans in the current outbreak have been traced to sexual transmission especially among men, who identify ourselves as gay or bisexual. The basis method for identification of agent in present time is PCR-RT targeting on the tumor necrosis factor (TNF) receptor gene. Usually monkeypox of human is mild, self-limiting disease. The symptoms of monkeypox are varied and non-specific. One of the most frequently observed clinical symptoms is lymphadenopathy. Most patients recover during some weeks. However, specific antiviral treatment – tecovirimat (S-246) and brincidofovir (CMX-001) – may be used for seriously ill or immunocompromised individuals. For prophylactic disease in present time are use vaccines JYNNEOSTM, ACAM2000R and Aventis Pasteur (APSV). Conclusion. General vaccination against monkeypox don't develop accordingly to modern recommendations WHO. Ring vaccination is recommended to conduct for suppression of spread virus in nidus of infection among population. Timely international coordination is needed to prevent the global spread of a disease with epidemic potential.

Abstract PO2-24-11: Hedgehog signaling influences tumor immunogenicity by the modulation of T cell populations in triple-negative breast cancer

Abstract Breast cancer is becoming more prevalent as it now makes up 30% of all new cancer cases yearly for U.S. women. Additionally, highly aggressive triple-negative breast cancer (TNBC) presents as immunologically “cold” tumors characterized by limited infiltration of anti-tumorigenic lymphocytes and the promotion of immunosuppressive cell populations. Therefore, it is essential to consider possible combinational therapies in treating primary tumors and in preventing metastases and recurrence. In the breast tumor microenvironment (TME), the presence and activity of regulatory T cells (Tregs) have been associated with poorer prognoses in breast cancer due to their ability to promote the progression of tumor growth and metastasis. Our group has extensively studied how the Hedgehog (Hh) signaling pathway can modulate the aggressiveness and the immune portfolio of the mammary TME, and we have recently reported the role of this pathway in regulating Treg activity and abundance. We have discovered that Hh inhibition can influence Treg-to-Th17 plasticity, promoting Tregs into a pro-inflammatory Th17-like phenotype (Tr17). As Tregs are highly influential to other immune populations of the TME, it is imperative to determine what phenotypic changes are induced in other T cell populations after systemic Hh inhibition in the mammary TME. We hypothesize that systemic Hh inhibition reshapes the tumor-immune microenvironment to be tumor-eradicating by influencing key immune populations of the mammary TME. Therefore, we further investigated how CD4+ and CD8+ T cells are influenced by systemic Hh blockade in a mammary carcinoma mouse model using single-cell RNA-Sequencing (scRNA-Seq) and R programming for data analyses and visualization. We sought to assess transcriptomic changes in tumoral T cells and to interpret how these elicited changes may be influencing the immunogenicity of the primary tumor. In these investigations, we found that systemic Hh inhibition modified the abundance and activation profile of CD4+ and CD8+ T cell populations within the primary tumor. As the infiltration and persistence of certain T cell subsets within the TME can influence tumor growth, dictate tumor recurrence, and contribute to immunotherapy responsiveness, it is essential to determine the mechanisms that modulates tumoral CD4+ and CD8+ T cells in the mammary TME. These studies will expand on the mechanism by which Hh signaling modulates mammary tumorigenesis systemically. This comprehensive work will also contribute to understanding the role of Hh signaling in modulating T cell subsets and inform future studies for innovative combinational therapeutic strategies to treat highly aggressive TNBC. Citation Format: Courtney Swain, Dominique Hinshaw, Heba Alsheikh, Brandon Metge, Lalita Shevde-Samant. Hedgehog signaling influences tumor immunogenicity by the modulation of T cell populations in triple-negative breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-24-11.

Immunomodulation of salivary gland function due to cancer therapy.

Functional salivary glands (SG) are essential for maintaining oral health, and salivary dysfunction is a persistent major clinical challenge. Several cancer therapies also have off-target effects leading to SG dysfunction. Recent advances highlight the role of SG immune populations in homeostasis, dysfunction and gland regeneration. Here, we review what is known about SG immune populations during development and postnatal homeostasis. We summarize recent findings of immune cell involvement in SG dysfunction following cancer treatments such as irradiation (IR) for head and neck cancers, immune transplant leading to graft-versus-host-disease (GVHD) and immune checkpoint inhibitor (ICI) treatment. The role of immune cells in SG in both homeostasis and disease, is an emerging field of research that may provide important clues to organ dysfunction and lead to novel therapeutic targets.