Differential responses of soil microbial biomass, diversity and interactions to land use intensity at a territorial scale

Impact of land use intensification on soil microbial communities across a territory remains poorly documented. Yet, it has to be deciphered to validate the results obtained at local and global scales by integrating the variations of environmental conditions and agricultural systems at a territorial scale. We investigated the impact of different land uses (from forest to agricultural systems) and associated soil management practices on soil molecular microbial biomass and diversity across a territory of 3300 km2 in Burgundy (France). Microbial biomass and diversity were determined by quantifying and high-throughput sequencing of soil DNA from 300 soils, respectively. Geostatistics were applied to map the soil macro-ecological patterns and variance partitioning analysis was used to rank the influence of soil physicochemical characteristics, land uses and associated practices on soil microbial communities. Geographical patterns differed between microbial biomass and diversity, emphasizing that distinct environmental drivers shaped these parameters. Soil microbial biomass was mainly driven by the soil organic carbon content and was significantly altered by agricultural land uses, with a loss of about 71 % from natural to agricultural ecosystems. The best predictors of bacterial and fungal richness were soil texture and pH, respectively. Microbial diversity was less sensitive than microbial biomass to land use intensification, and fungal richness appeared more impacted than bacteria. Co-occurrence network analysis of the interactions among microbial communities showed a decline of about 95 % of network complexity with land use intensification, which counterbalanced the weak response of microbial diversity. Grouping of the 147 cropland plots in four clusters according to their agricultural practices confirmed that microbial parameters exhibited different responses to soil management intensification, especially soil tillage and crop protection. Our results altogether allow evaluating the different levels of microbial parameters' vulnerability to land use intensity at a territorial scale.

Abstract 4135: A novel plasma cell-based mechanism of action of adenosine immunomodulation and A2AR antagonism

High levels of extracellular adenosine, often found in the tumor microenvironment (TME), promote immune suppression mainly through the A2A receptor (A2AR) expressed by tumor-infiltrating immune cells. Inupadenant (formerly known as EOS100850) is an oral, non-brain penetrant, potent and highly selective small molecule antagonist of A2AR. In a Phase I/Ib clinical trial (NCT02740985), inupadenant as monotherapy showed initial evidence of clinical benefit in subjects with advanced solid tumors. In this study, tumor biopsies with a high number of A2AR-expressing immune cells at baseline were associated with response or stable disease.We now report that infiltration of A2AR+ cells was strongly correlated with the expression of B- and, more specifically, antibody-secreting cell (ASC)-related genes, as assessed by gene expression (Nanostring) and immunohistochemistry (IHC), hinting at a potential novel role for A2AR in B cell biology. Therefore, we explored the expression and function of A2AR in human B cells. Immunocytochemistry staining of A2AR on sorted tonsillar B cell subsets showed that A2AR was predominantly expressed on ASCs, including plasma cells and plasma blasts versus naïve or memory B cells. The preferential expression of A2AR by ASCs was confirmed on NSCLC tissues by multiplex immunofluorescence. In addition to A2AR, ASCs expressed other adenosine pathway markers such as CD39, suggesting that the adenosine pathway is a key mechanism through which ASC functions may be modulated. Using B cells derived from peripheral blood, the A2AR agonist CGS-21680 was shown to inhibit the maturation of B cells into plasma cells, and that maturation could be fully restored by inupadenant. CGS-21680 did not affect B cell or plasma cell viability, indicating that the effect of A2AR signaling on plasma cell differentiation is not due to preferential plasma cell death in culture. Importantly, baseline expression of B cell- and ASC-related markers measured by Nanostring and IHC was associated with response or stable disease to inupadenant monotherapy, supporting the notion that these cells may be a novel target of inupadenant. This is in line with recent reports showing that B cells, plasma cells and tertiary lymphoid structures are associated with favorable responses to cancer immunotherapy. Interestingly, four out of the five non-progressors treated with inupadenant as monotherapy and with available biomarker data showed a reduction in ASC infiltration after inupadenant treatment, suggesting that inupadenant may promote terminal plasma cell differentiation and migration out of the tumor tissue and to the bone marrow.Altogether, these data support a novel plasma cell-centric mechanism of action of inupadenant, which may complement its reported T cell-mediated anti-tumor activity.

Citation Format: Chiara Martinoli, Paola Tieppo, Marjorie Mercier, Hussein Shehade, Noemie Wald, Anais Vezzu, Annelise Hermant, Boris Pirlot, Stephanie Ma, Maurizio Ceppi, Yvonne McGrath, Maura Rossetti. A novel plasma cell-based mechanism of action of adenosine immunomodulation and A2AR antagonism. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4135.

Abstract 4149: Extensive characterization of the adenosine pathway in human solid tumors gives a hint on cancer indication selection for the A2A receptor antagonist EOS100850

Extracellular adenosine is an immunosuppressive metabolite generated by sequential action of the two ectonucleotidases CD39 and CD73. Tissue hypoxia, which is frequently observed in neopleastic tissues, increases CD39 and CD73 expression, and is a major driver of extracellular adenosine accumulation. High levels of adenosine, predominantly signaling through the A2A receptor (A2AR), dampen innate and adaptive immune cell responses, leading to suppression of antitumor immunity. We therefore developed EOS100850, a potent and highly selective A2A receptor antagonist to treat a wide range of tumor types. With the aim to support selection of cancer indications for EOS100850, we used immunohistochemistry and computer-assisted image analysis to extensively characterize the expression and spatial distribution of markers of the adenosine pathway and the extent of lymphocyte infiltration in ten tumor types. First, 318 primary tumor specimens included in disease-specific tissue microarrays from nine cancer indications were screened for expression of CD39, CD73 and infiltration of A2AR+, CD8+ and Foxp3+ cells. CD39 and CD73 were expressed by immune cells, endothelial cells and other stromal cells as well as by tumor cells, and their expression was increased in hypoxic tumor regions. Expression levels of the two adenosine-generating enzymes were variable among the analyzed cancer types, with lung and gastric tumors displaying the highest levels of expression of CD39 (78% and 95% of samples with high CD39 expression, respectively) and gastric, uterine and lung cancers displaying the highest levels of CD73 (>70% of samples with high CD73 expression). A2AR staining was observed on different immune cell populations, and significantly correlated with CD8+ and Foxp3+ cell densities (p values <0.0001). A2AR+ immune cells were frequently detected in lung, gastric and head and neck tumors (>80% positive samples) but not in kidney and prostate tumors (<20% positive samples). To encompass the inherent heterogeneity of tumor tissues, the expression and spatial distribution of CD39, CD73, A2AR and lymphocyte populations were further analyzed in several lung, colorectal and breast primary tumor resections. These tumor types display high, medium and low levels of the adenosine cloud markers, respectively. CD39 expression as well as densities of A2AR+, CD8+ and Foxp3+ cells were all higher in the tumor surrounding stroma than in the center of the tumor in the three cancer types. Moreover, CD39 and A2AR were significantly correlated with CD8+ and Foxp3+ cell densities in the tumor center but not in the stroma. Altogether these data strongly support the relevance of targeting A2AR and the adenosine pathway in immuno-oncology, and pave the way to the identification of the cancer types that will benefit more from EOS100850.

Citation Format: Noemie Wald, Chiara Martinoli, Marjorie Mercier, Annelise Hermant, Florence Nyawouame, Joao Marchante, Charlotte Moulin, Vanesa Bol, Stefano Crosignani, Veronique Bodo. Extensive characterization of the adenosine pathway in human solid tumors gives a hint on cancer indication selection for the A2A receptor antagonist EOS100850 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4149.

Abstract 3278: EOS100850 potently restores adenosine A2Areceptor-dependent suppression of T cell function in the adenosine rich tumor microenvironment

Adenosine is a potent immunosuppressive metabolite that is often found elevated in the extracellular tumor microenvironment (TME). We determined concentrations of extracellular adenosine in different patient-derived xenografts (PDX) from 7 different histological types, in which extracellular median adenosine concentrations were shown to range from 0.5 to 45 µM, with the overall median adenosine concentration being about 4.5 µM. Adenosine concentration in the non-tumorous subcutaneous space in mice was measured at about 0.5 µM. Adenosine in the TME is generated mainly by the concerted action of the ectonucleotidases CD39 and CD73. The expression of these enzymes across various cancer types was evaluated by flow cytometry in dissociated human tumor biopsies. CD73 and CD39 were strongly expressed by multiple tumor-infiltrating T cell types. Tumor-associated myeloid cells mostly expressed CD39 and high frequencies of EpCAM+ tumor cells strongly expressed CD73. These data strongly suggest that adenosine levels could be further increased compared to non-immune-infiltrated PDX.Adenosine activates 4 G protein-coupled receptor subtypes, of which the adenosine A2A receptor in particular suppresses innate and adaptive immune cell responses leading to suppression of anti-tumor immunity. Among the 4 adenosine receptors, we confirmed the A2A receptor as the main adenosine receptor expressed in CD4+ and CD8+ T cells, natural killer cells, monocytes, and dendritic cells. Stimulation of these immune cell subsets further increased A2A receptor expression. A2B receptor was expressed at very low levels in stimulated CD4+ and CD8+ T cells and in monocytes and immature DCs. A1 and A3 receptors were hardly detected in these subsets of immune cells. EOS100850, a highly potent and selective A2A receptor antagonist, was characterized in various in vitro functional assays. A2A receptor activation by a selective agonist suppressed priming of mouse OVA-specific OT1 T cells and subsequent antigen-specific CD8+ T cell cytotoxicity in a co-culture assay of effector CD8+ T cells and target cancer cells. This A2A receptor-mediated immune suppression was potently and dose-dependently reversed by EOS100850. In a mixed lymphocyte reaction between human dendritic cells and T cells, EOS100850 blocked the adenosine-dependent inhibition of T cell proliferation and secretion of IFNg, TNFa and IL-2 in a dose-dependent manner. In conclusion, extracellular adenosine as well as adenosine pathway components were strongly present across multiple tumor types, and across multiple tumor-associated cell types. In addition, EOS100850, a highly potent A2A receptor antagonist, reversed A2A receptor-mediated suppression of T cell priming, cytotoxicity, cytokine production and proliferation.

Citation Format: Erica Houthuys, Paola Basilico, Veronique Bodo, Margreet Brouwer, Michel Detheux, Gregory Driessens, Bruno Gomes, Annelise Hermant, Catherine Hoofd, Florence Lambolez, Xavier Leroy, Reece Marillier, Chiara Martinoli, Marjorie Mercier, Florence Nyawouame, Shruthi Prasad, Ariane Scoumanne, Stefano Crosignani. EOS100850 potently restores adenosine A2Areceptor-dependent suppression of T cell function in the adenosine rich tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3278.

[Obstructive lung diseases in a French prison: results of systematic screening]

BACKGROUND

French prisoners have health problems that have been inadequately treated before imprisonment. This population has insufficient access to the healthcare system. Addictive behaviours, particularly smoking, are widespread. The aim of the study is to evaluate the prevalence of airflow limitation by using a primary care screening method adapted for the correctional facility and its inmates.

METHOD

The screening of airflow limitation using a mobile spirometer is carried out in inmates consulting the primary care unit (UCSA) of Amiens prison. Patients consulting the UCSA between 16 August and 17 October 2006 and providing their consent are included in the study. The criteria for exclusion are: a counter-indication for spirometry, poor compliance with the effort of forced expiry after eight efforts, as well as refusal to take part in the study. The descriptive statistical analysis includes all of the quantitative and qualitative variables.

RESULTS

Among the 210 patients included in the sample, only five patients refused to take part in the study. Their mean age was 37 (range: 16-65) and 90% were men. Ninety percent of this population were active smokers. Sixty percent of these smokers would like to quit. The spirometry detected 11% undiagnosed airflow limitation: 11 prisoners suffered from chronic obstructive lung disease and 13 prisoners suffered from asthma.

DISCUSSION

Given the relative youth and high risk nature of these diagnosed patients, the potential for the long or short term aggravation, and a growing recognition of the seriousness of exposure to tobacco, the authors suggest that the systematic screening of inmates for airflow limitation may be used to assist in detecting serious health issues. Along with new French antismoking legislation, this screening may enable primary care workers to better reduce smoking habits in prisons.

Detection of benzo[a]pyrene-DNA adducts from leukocytes from heavy smokers

Benzo[a]pyrene is a cigarette smoke component that is metabolized in the human body to the diol-epoxide derivative benzo[a]pyrene-trans- 7,8-dihydrodiol-9,10-epoxide (BPDE-I), which is the final carcinogen. BPDE-I binds covalently to DNA, producing BPDE-I-DNA adducts. A competitive immunoenzymetric assay was used to measure BPDE-I-DNA adducts in blood samples from 58 heavy smokers, 32 men and 26 women, attending a smoking cessation clinic. Cigarette consumption was evaluated based on urinary continine levels. None of the subjects worked in jobs involving exposure to polycyclic aromatic hydrocarbons (e.g., benzo[a]pyrene). Concentrations of BPDE-I-DNA adducts varied with cigarette consumption, ranging from 10.00 to 28.20 fmol/50 micrograms of DNA.

[Labor under peridural anesthesia. Experience at the Maternity Center of the Amiens CHRU]

The study has been carried out on 476 epidural deliveries. 69 per cent of the patients were satisfied. Amongst the 31 per cent of unsatisfied, most claimed that the analgesia was not sufficient, mainly due to delayed re-injections. Instead of a continuous administration, the authors prefer the use of a bolus which is better adapted to the different times of labour. 80 per cent of the patients who had a caesarian delivery under epidural anaesthetic were very satisfied. The efficacy of the re-injection for post-operative analgesia is also to be noted (92 per cent success). Finally, whatever the stage of perfection of the epidural technique, it is always better to associate the latter with a good psychoprophylaxis.

[Bourneville's disease of the bones or metastasis? Apropos of a case]

Tuberous sclerosis or Bourneville's disease is a phakomatosis with common but paucisymptomatic bone localisations. Some osseous lesions, of osteosclerotic type, can be radiologically diagnosed as primary or secondary malignant disorders. We describe a case of Bourneville's disease with bone involvement, radiologically characterized by osteosclerosis areas of the spine and the pelvis. Interestingly, bone scintiscan was normal. The absence of primary malignancy, the stability of control bone X-ray films, the clinical status and the family history, together with the pathognomonic radiological feature of the hands support the diagnosis of tuberous sclerosis with bone involvement.

Intracranial pressure changes in patients with head trauma during haemodialysis

Intracranial hypertension and acute renal failure are frequent complications in polytraumatized patients with head trauma. This paper deals with the evolution of intracranial pressure during haemodialysis in two cases of traumatic coma. Significant changes in intracranial pressure were noted. Increase of intracranial pressure during haemodialysis was 7.6 mmHg for the first patient and 4.6 mmHg for the second patient. Prophylactic measures are discussed.

[Long-term results of intermittent ventilatory assistance for 74 severe obstructive chronic respiratory insufficient patients (PaCO2 greater than 50 Torr) ventilated for more than a year (author's transl)]

From 1967 to 1978, home assisted ventilation (HAD) was applied to 74 severe chronic respiratory insufficient patients (67 COPD-7 restrictive). These patients used volume generators through mouth piece, except 3 of them who had a tracheostomy. The main results of this study are a highly statistically significant decrement (P less than 0,001) of the hospitalization durations and of the frequency of ARF, as well as an improvement of the survival duration in front of a non-tested group, and a significant decrease of haematocrit (less than 0,05) and P.V.R. (P less than 0,01). But blood gases and functional tests are not statistically different. Age (greater than 55 years) and delay after first ARF (greater than 2 years) when starting HAD are considered as pejorative factors.