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Dorvilleidae Chamberlin, 1919 is a family of Annelida containing some of the smallest 'polychaetes' species, being poorly studied worldwide, and with little knowledge regarding its diversity and occurrence. Samples obtained in oceanographic campaigns performed in the Southwest Atlantic Ocean (Brazilian coast) revealed a high number of specimens of dorvilleids, adding to our knowledge of the family's biodiversity. A detailed morphological analysis of these organisms has revealed a new genus, Ceciamaralia gen. nov. , with two new species. The new genus differs from other Dorvilleidae genera in (i) the robust and enlarged pharynx which are frequently everted, (ii) unique composition of maxillae, with an elongated pair of serrated basal plates and one pair of anterior free maxillary plates with a long and thin anterior spine and (iii) ventral cirri present only in few first chaetigers. Ceciamaralia lanai gen. et sp. nov. is characterized by the presence of a broad and large dorsal cirrus on a few anterior parapodia and by furcate chaeta in supra-acicular fascicles. While Ceciamaralia nonatoi gen. et sp. nov. presents one geniculate chaeta instead of one furcate, the absence of dorsal cirri and, in some specimens, the absence of palps. A cladistic analysis supported the monophyly of Ceciamaralia gen. nov. by four synapomorphies related to the unique morphology of its maxillae, pharynx and appendages. This study is part of several recent taxonomic studies aiming to elucidate and increase the knowledge of Dorvilleidae, since it is part of a Ph.D project focused on the family., Competing Interests: The authors declare that they have no competing interests., (© 2024 Bonaldo et al.)

Bispecific antibodies (bsAbs) are engineered molecules designed to target two different epitopes or antigens. The mechanism of action is determined by the bsAb molecular targets and structure (or format), which can be manipulated to create variable and novel functionalities, including linking immune cells with tumor cells, or dual signaling pathway blockade. Several bsAbs have already changed the treatment landscape of hematological malignancies and select solid cancers. However, the mechanisms of resistance to these agents are understudied and the management of toxicities remains challenging. Herein, we review the principles in bsAb engineering, current understanding of mechanisms of action and resistance, data for clinical application, and provide a perspective on ongoing challenges and future developments in this field., Competing Interests: Declaration of interests None declared by authors., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The causative agent of human Q fever, Coxiella burnetii, is highly adapted to infect alveolar macrophages by inhibiting a range of host responses to infection. Despite the clinical and biological importance of this pathogen, the challenges related to genetic manipulation of both C. burnetii and macrophages have limited our knowledge of the mechanisms by which C. burnetii subverts macrophages functions. Here, we used the related bacterium Legionella pneumophila to perform a comprehensive screen of C. burnetii effectors that interfere with innate immune responses and host death using the greater wax moth Galleria mellonella and mouse bone marrow-derived macrophages. We identified MceF (Mitochondrial Coxiella effector protein F), a C. burnetii effector protein that localizes to mitochondria and contributes to host cell survival. MceF was shown to enhance mitochondrial function, delay membrane damage, and decrease mitochondrial ROS production induced by rotenone. Mechanistically, MceF recruits the host antioxidant protein Glutathione Peroxidase 4 (GPX4) to the mitochondria. The protective functions of MceF were absent in primary macrophages lacking GPX4, while overexpression of MceF in human cells protected against oxidative stress-induced cell death. C. burnetii lacking MceF was replication competent in mammalian cells but induced higher mortality in G. mellonella, indicating that MceF modulates the host response to infection. This study reveals an important C. burnetii strategy to subvert macrophage cell death and host immunity and demonstrates that modulation of the host antioxidant system is a viable strategy to promote the success of intracellular bacteria.

Lumbrineriopsisdulcis sp. nov. is morphologically described from the continental shelf and slope of Espírito Santo and the Campos Basin of Rio de Janeiro state, southeastern Brazil, at depths between 14 and 400 m. Lumbrineriopsismucronata is the only species of the genus recorded until now in Brazil. The new species differs from other congeneric species in its jaw-apparatus morphology with unfused mandibles and a fixed number of simple limbate chaetae and simple, bidentate, hooded hooks in each parapodium. This paper aims to fill the gap in knowledge on the family Lumbrineridae, which has not been studied in Brazil for the last 25 years and provides the first record of the genus from Espírito Santo and Rio de Janeiro states. This record is significant given the damage to the marine ecosystem of the Espírito Santo region due to the 2015 rupture of the Samarco mining company dam, the largest environmental disaster in Brazil's history. In addition, this region has important environmental conservation units such as Costa das Algas Environmental Protection Area, Santa Cruz Wildlife Refuge, and Comboios Biological Reserve. All these preserved areas are of paramount importance for the protection of marine biological diversity., Competing Interests: The authors have declared that no competing interests exist., (Nálita Maria Scamparle Teodoro, Tatiana Menchini Steiner, Antonia Cecília Zacagnini Amaral.)

Germinal centers (GCs), transient structures within B cell follicles and central to affinity maturation, require the coordinated behavior of T and B cells. IL-21, a pleiotropic T cell-derived cytokine, is key to GC biology through incompletely understood mechanisms. By genetically restricting production and receipt of IL-21 in vivo, we reveal how its independent actions on T and B cells combine to regulate the GC. IL-21 established the magnitude of the GC B cell response by promoting CD4 + T cell expansion and differentiation in a dose-dependent manner and with paracrine activity. Within GC, IL-21 specifically promoted B cell centroblast identity and, when bioavailability was high, plasma cell differentiation. Critically, these actions may occur irrespective of cognate T-B interactions, making IL-21 a general promoter of growth as distinct to a mediator of affinity-driven selection via synaptic delivery. This promiscuous activity of IL-21 explains the consequences of IL-21 deficiency on antibody-based immunity., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Different pathways for autotrophic CO 2 fixation can be recognized by the presence of genes for their specific key enzymes. On this basis, (meta)genomic, (meta)transcriptomic, or (meta)proteomic analysis enables the identification of the role of an organism or a distinct pathway in primary production. However, the recently discovered variant of the reductive tricarboxylic acid (rTCA) cycle, the reverse oxidative tricarboxylic acid (roTCA) cycle, lacks unique enzymes, a feature that makes it cryptic for bioinformatics analysis. This pathway is a reversal of the widespread tricarboxylic acid (TCA) cycle. The functioning of the roTCA cycle requires unusually high activity of citrate synthase, the enzyme responsible for citrate cleavage, as well as elevated CO 2 partial pressures. Here, we present a detailed description of the protocol we used for the identification of the roTCA cycle in members of Desulfurellaceae . First, we describe the anaerobic cultivation of Desulfurellaceae at different CO 2 concentrations with a method that can be adapted to the cultivation of other anaerobes. Then, we explain how to measure activities of enzymes responsible for citrate cleavage, malate dehydrogenase reaction, and the crucial carboxylation step of the cycle catalyzed by pyruvate synthase in cell extracts. In conclusion, we describe stable isotope experiments that allow tracking of the roTCA cycle in vivo , through the position-specific incorporation of carbon-13 into amino acids. The label is provided to the organism as 13 CO 2 or [1- 13 C]glutamate. The same key methodology can be used for the reliable evaluation of the functioning of the roTCA cycle in any organism under study. This pathway is likely to participate, completely unseen, in the metabolism of various microorganisms. Graphic abstract., Competing Interests: Competing interestsThe authors have no conflicts of interest or competing interests., (Copyright © 2022 The Authors; exclusive licensee Bio-protocol LLC.)

Marginal zone (MZ) B cells produce broad-spectrum antibodies that protect against infection early in life. In some instances, antibody production requires MZ B cells to display pathogen antigens bound to major histocompatibility complex class II (MHC II) molecules to T cells. We describe the trogocytic acquisition of these molecules from conventional dendritic cells (cDCs). Complement component 3 (C3) binds to murine and human MHC II on cDCs. MZ B cells recognize C3 with complement receptor 2 (CR2) and trogocytose the MHC II-C3 complexes, which become exposed on their cell surface. The ubiquitin ligase MARCH1 limits the number of MHC II-C3 complexes displayed on cDCs to prevent their elimination through excessive trogocytosis. Capture of C3 by MHC II thus enables the transfer of cDC-like properties to MZ B cells.

Antibodies are hallmarks of most effective vaccines. For successful T-dependent antibody responses, conventional dendritic cells (cDC) have been largely attributed the role of priming T cells. By contrast, follicular dendritic cells and macrophages have been seen as responsible for B cell activation, due to their strategic location within secondary lymphoid tissues and capacity to present native antigen to B cells. This review summarizes the mounting evidence that cDC can also present native antigen to B cells. cDC2 have been the main subset linked to humoral responses, based largely on their favorable location, capacity to prime CD4 + T cells, and ability to present native antigen to B cells. However, studies using strategies to deliver antigen to receptors on cDC1, reveal this subset can also contribute to naïve B cell activation, as well as T cell priming. cDC1 location within lymphoid tissues reveals their juxtaposition to B cell follicles, with ready access to B cells for presentation of native antigen. These findings support the view that both cDC1 and cDC2 are capable of initiating humoral responses provided antigen is captured by relevant surface receptors attuned to this process. Such understanding is fundamental for the development of innovative humoral vaccination approaches., (© 2021 Wiley-VCH GmbH.)

Helicobacter pylori displays a worldwide infection rate of about 50%. The Gram-negative bacterium is the main reason for gastric cancer and other severe diseases. Despite considerable knowledge about the metabolic inventory of H. pylori, carbon fluxes through the citrate cycle (TCA cycle) remained enigmatic. In this study, different 13 C-labeled substrates were supplied as carbon sources to H. pylori during microaerophilic growth in a complex medium. After growth, 13 C-excess and 13 C-distribution were determined in multiple metabolites using GC-MS analysis. [U- 13 C 6 ]Glucose was efficiently converted into glyceraldehyde but only less into TCA cycle-related metabolites. In contrast, [U- 13 C 5 ]glutamate, [U- 13 C 4 ]succinate, and [U- 13 C 4 ]aspartate were incorporated at high levels into intermediates of the TCA cycle. The comparative analysis of the 13 C-distributions indicated an adaptive TCA cycle fully operating in the closed oxidative direction with rapid equilibrium fluxes between oxaloacetate-succinate and α-ketoglutarate-citrate. 13 C-Profiles of the four-carbon intermediates in the TCA cycle, especially of malate, together with the observation of an isocitrate lyase activity by in vitro assays, suggested carbon fluxes via a glyoxylate bypass. In conjunction with the lack of enzymes for anaplerotic CO 2 fixation, the glyoxylate bypass could be relevant to fill up the TCA cycle with carbon atoms derived from acetyl-CoA., (© 2021 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.)

It has recently been shown that in anaerobic microorganisms the tricarboxylic acid (TCA) cycle, including the seemingly irreversible citrate synthase reaction, can be reversed and used for autotrophic fixation of carbon 1,2 . This reversed oxidative TCA cycle requires ferredoxin-dependent 2-oxoglutarate synthase instead of the NAD-dependent dehydrogenase as well as extremely high levels of citrate synthase (more than 7% of the proteins in the cell). In this pathway, citrate synthase replaces ATP-citrate lyase of the reductive TCA cycle, which leads to the spending of one ATP-equivalent less per one turn of the cycle. Here we show, using the thermophilic sulfur-reducing deltaproteobacterium Hippea maritima, that this route is driven by high partial pressures of CO 2 . These high partial pressures are especially important for the removal of the product acetyl coenzyme A (acetyl-CoA) through reductive carboxylation to pyruvate, which is catalysed by pyruvate synthase. The reversed oxidative TCA cycle may have been functioning in autotrophic CO 2 fixation in a primordial atmosphere that is assumed to have been rich in CO 2 .

Follicular dendritic cells and macrophages have been strongly implicated in presentation of native Ag to B cells. This property has also occasionally been attributed to conventional dendritic cells (cDC) but is generally masked by their essential role in T cell priming. cDC can be divided into two main subsets, cDC1 and cDC2, with recent evidence suggesting that cDC2 are primarily responsible for initiating B cell and T follicular helper responses. This conclusion is, however, at odds with evidence that targeting Ag to Clec9A (DNGR1), expressed by cDC1, induces strong humoral responses. In this study, we reveal that murine cDC1 interact extensively with B cells at the border of B cell follicles and, when Ag is targeted to Clec9A, can display native Ag for B cell activation. This leads to efficient induction of humoral immunity. Our findings indicate that surface display of native Ag on cDC with access to both T and B cells is key to efficient humoral vaccination., (Copyright © 2020 by The American Association of Immunologists, Inc.)

Liver resident-memory CD8 + T cells (T RM cells) can kill liver-stage Plasmodium -infected cells and prevent malaria, but simple vaccines for generating this important immune population are lacking. Here, we report the development of a fully synthetic self-adjuvanting glycolipid-peptide conjugate vaccine designed to efficiently induce liver T RM cells. Upon cleavage in vivo, the glycolipid-peptide conjugate vaccine releases an MHC I-restricted peptide epitope (to stimulate Plasmodium -specific CD8 + T cells) and an adjuvant component, the NKT cell agonist α-galactosylceramide (α-GalCer). A single dose of this vaccine in mice induced substantial numbers of intrahepatic malaria-specific CD8 + T cells expressing canonical markers of liver T RM cells (CD69, CXCR6, and CD101), and these cells could be further increased in number upon vaccine boosting. We show that modifications to the peptide, such as addition of proteasomal-cleavage sequences or epitope-flanking sequences, or the use of alternative conjugation methods to link the peptide to the glycolipid improved liver T RM cell generation and led to the development of a vaccine able to induce sterile protection in C57BL/6 mice against Plasmodium berghei sporozoite challenge after a single dose. Furthermore, this vaccine induced endogenous liver T RM cells that were long-lived (half-life of ~425 days) and were able to maintain >90% sterile protection to day 200. Our findings describe an ideal synthetic vaccine platform for generating large numbers of liver T RM cells for effective control of liver-stage malaria and, potentially, a variety of other hepatotropic infections., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Liver-resident memory CD8 + T (T RM ) cells remain in and constantly patrol the liver to elicit rapid immunity upon antigen encounter and can mediate efficient protection against liver-stage Plasmodium infection. This finding has prompted the development of immunization strategies where T cells are activated in the spleen and then trapped in the liver to form T RM cells. Here, we identify PbRPL6 120-127 , a H2-K b -restricted epitope from the putative 60S ribosomal protein L6 (RPL6) of Plasmodium berghei ANKA, as an optimal antigen for endogenous liver T RM cell generation and protection against malaria. A single dose vaccination targeting RPL6 provided effective and prolonged sterilizing immunity against high dose sporozoite challenges. Expressed throughout the parasite life cycle, across Plasmodium species, and highly conserved, RPL6 exhibits strong translation potential as a vaccine candidate. This is further advocated by the identification of a broadly conserved, immunogenic HLA-A ∗ 02:01-restricted epitope in P. falciparum RPL6., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

B cells are efficiently activated by antigens presented on cell membranes, which provide opportunity for receptor cross-linking and antigen capture. The two main cell types implicated in native antigen presentation to B cells are follicular dendritic cells (FDC), which reside in B cell follicles, and CD169 + macrophages, which line the antigen-exposed surfaces of these follicles in both the lymph nodes and the spleen. There is mounting evidence, however, that conventional dendritic cells (cDC) can also participate in native antigen presentation to B cells. This underappreciated role, largely hidden by the simultaneous need for cDC to participate in T cells priming, appears to be primarily mediated by the type 2 subset of cDC (cDC2), but may also be a function of cDC1. Better understanding of how cDC participate in B cell priming is likely to improve our capacity to develop effective humoral vaccines., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

Liver tissue-resident memory T (Trm) cells migrate throughout the sinusoids and are capable of protecting against malaria sporozoite challenge. To gain an understanding of liver Trm cell development, we examined various conditions for their formation. Although liver Trm cells were found in naive mice, their presence was dictated by antigen specificity and required IL-15. Liver Trm cells also formed after adoptive transfer of in vitro-activated but not naive CD8 + T cells, indicating that activation was essential but that antigen presentation within the liver was not obligatory. These Trm cells patrolled the liver sinusoids with a half-life of 36 days and occupied a large niche that could be added to sequentially without effect on subsequent Trm cell cohorts. Together, our findings indicate that liver Trm cells form as a normal consequence of CD8 + T cell activation during essentially any infection but that inflammatory and antigenic signals preferentially tailor their development., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)

It is hypothesized that the uremic toxin indoxyl sulfate (IS) plays a role in the pathogenesis of renal anemia. To further explore that hypothesis, we examined the effects of IS on reactive oxygen species (ROS) production, levels of reduced glutathione (GSH), and erythrocyte death (eryptosis) in red blood cells (RBC) from healthy controls (CON-RBC) and hemodialyzed patients (HD-RBC), respectively. RBC were incubated either in either TRIS-Glc-BSA buffer or IS at concentrations of 0.01, 0.09, and 0.17 mM, respectively. We measured ROS generation (expressed as % of DCFH-DA positive RBC), eryptosis (expressed as % of annexin-V positive RBC), and GSH levels after 6, 12, and 24 h. When incubated in buffer, ROS production was approximately seven-fold higher at all time points HD-RBC when compared to CON-RBC. Incubation with IS increased ROS production in CON-RBS dose-dependently up to 10-fold. Eryptosis in buffer-incubated HD-RBC was up to seven-fold higher as compared to COB-RBC. Incubation of CON-RBC with IS increased the eryptosis rate dose-dependently up to 6-fold. Pretreatment of CON-RBC with the organic anion transporter 2 (OAT2) specific inhibitor ketoprofen or with NADPH oxidase inhibitor diphenyleneiodonium-Cl blunted the IS effect on both ROS production and eryptosis induction. While GSH levels in HD-RBC were reduced when compared to CON-RBC, they were not affected by IS incubation. In summary, IS increases ROS generation and eryptosis in CON-RBC by an activity dependent of the IS influx through OAT2, and NADPH oxidase activity-dependent, and a GSH-independent mechanism. These findings lend support to a putative role of IS in the pathogenesis of renal anemia.

We report a one-pot formation of 2,4-diolefinic or 2,4,6-triolefinic monocarboxylic acids, R-(CH[bond, double bond]CH) 2or3 -COOH, by decarboxylative condensation of an optionally α,β-unsaturated aldehyde with glutaconic acid, HOOC-CH 2 -CH[bond, double bond]CH-COOH as straight chain C4-extender. The reaction is broadly applicable to saturated and unsaturated aldehydes and opens up a simple gateway to valuable organic products and reactive intermediates., (© 2017 The Authors.)

Immune system dysfunction is a common condition in chronic kidney disease (CKD). The present study investigated the effect of p-Cresyl sulfate (pCS) on human cell line U937 monocyte-derived macrophages (MDM) activity. MDM (1×10 6 cells/mL) were incubated with pCS (10, 25, or 50μg/mL), with or without lipopolysaccharide (LPS; 25ng/mL) and then evaluated NO production, phagocytosis and antigen-presenting molecules expression (HLA-ABC, HLA-DR, CD80 and CD86). All analyses were performed by flow cytometry. All pCS concentrations were able to increase NO production (49±12.1%, 39.8±7.75%, 43.7±11.9%, respectively) compared to untreated cells (4.35±3.34%) after 6h incubation but only the lowest concentration increased this production after 12h (82.9±8.6%, 61±7.2%, 40.8±11.7%). Combined with LPS, the same results were observed. Regarding to phagocytosis, all concentrations were able to induce bead engulfment (35.4±2.71%, 30±3.04%, 23.28±4.58%). In addition, pCS (50μg/mL) was able to increase HLA-ABC and CD80 expression, showed a slight effect on HLA-DR expression and, no difference in basal CD86 levels. pCS can induce an increased oxidative burst and phagocytosis by human macrophages while no modulation of HLA-DR or CD86 expression was induced. Together, these results suggest that pCS induces macrophage activation but interfere in antigen processing, leading to a failure in adaptive immune response in CKD., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: We tested the effect of uremia on red blood cell (RBC) eryptosis, CD14++/CD16+ monocytes and erythrophagocytosis., Design: RBC and monocytes from chronic kidney disease (CKD) stages 3/4 (P-CKD3/4) or hemodialysis (HD) patients and healthy controls (HCs) cells incubated with sera pools from patients with CKD stages 2/3 (S-CKD2/3) or 4/5 (S-CKD4/5) were evaluated to assess eryptosis, monocyte phenotypes and reactive oxygen species (ROS) by cytometer. Erythrophagocytosis was evaluated by subsequent co-incubation of preincubated HC-monocytes and autologous-RBC., Results: HC-eryptosis (1.3 ± 0.9%) was lower than in HD (4.3 ± 0.5%) and HC-RBC incubated with S-CKD4/5 (5.6 ± 1%). CD14++/CD16+ were augmented in P-CKD3/4 (34.6 ± 8%) and HC-monocytes incubated with S-CKD4/5 (26.4 ± 7%) than in HC (5.4 ± 1%). In these cells, ROS was increased (44.5 ± 9%; control 9.6 ± 2%) and inhibited by N-acetylcysteine (25 ± 13%). Erythrophagocytosis was increased in CD14++/CD16+ (60.8 ± 10%) than in CD14++/CD16- (15.5 ± 2%)., Conclusions: Sera pools from CKD patients increase eryptosis and promote a proinflammatory monocyte phenotype. Both processes increased erythrophagocytosis, thereby suggesting a novel pathway for renal anemia., (© 2016 S. Karger AG, Basel.)

Background: Reconstruction of the medial patellofemoral ligament has been proven to restore stability in patients with lateral patellar instability. No study to date has examined the results in a patient population with the predisposing factor of femoral trochlear dysplasia., Hypothesis: Reconstruction of the medial patellofemoral ligament restores stability and provides pain relief in patients who have lateral patellar instability in association with trochlear dysplasia., Study Design: Case series; Level of evidence, 4., Methods: Thirty-four patients with chronic patellar instability and trochlear dysplasia were treated with medial patellofemoral ligament reconstruction using an adductor tendon autograft, bone-quadriceps tendon autograft, or bone-patellar tendon allograft. All patients were evaluated preoperatively and postoperatively with Kujala, Lysholm, and Tegner scores at a minimum of 24 months., Results: Thirty-four patients were followed for a mean of 66.5 months (range, 24-130 months) after surgery. Kujala scores improved from 53.3 to 90.7, Lysholm scores improved from 52.4 to 92.1, and Tegner activity scores improved from 3.1 to 5.1. All improvements were highly statistically significant (P < .001). No statistical difference was found between the postoperative Lysholm, Kujala, and Tegner scores and the degree of dysplasia, graft type, or degree of symptoms. There were 85.3% and 91.1% good and excellent results based on Kujala and Lysholm scores, respectively. No recurrent dislocations have occurred., Conclusion: Medial patellofemoral ligament reconstruction provides excellent long-term pain relief and functional return in patients with patellar instability and femoral trochlear dysplasia. In addition, reconstruction prevents recurrent dislocation, despite the diminished bony constraint of a dysplastic trochlea.