Biology subjects

Schneiderhan-Marra, N.

Publications and source records attributed to Schneiderhan-Marra, N..

10 recordsLinked to original sources

bioRxiv2026

Dual-Layer Serological Encoding: Integrating Pathogen-Derived and Host-Reactive Peptide Signatures Reveals Complementary Dimensions of HIV Immune Response

Serological diagnostics traditionally rely on pathogen-derived antigens to detect infection-specific antibody responses. Chronic infections also induce systemic immune remodeling that may be reflected in global antibody reactivity patterns beyond antigen specificity. Here we evaluate a dual-layer serological framework combining HIV-derived peptides with a host-derived peptide library designed to capture distributed antibody reactivity patterns. Using strict nested cross-validation in a cohort of 105 individuals, pathogen-derived 12-mer peptides achieved high classification performance with an AUC of 0.891, whereas the 10-mer host-based peptide library alone yielded moderate but statistically significant discrimination with an AUC of 0.805. Integration via regularized stacking resulted in only a modest additive improvement, reaching an AUC of 0.897, indicating partial redundancy in diagnostic ranking. In contrast, entropy and inequality analyses revealed substantial immune repertoire restructuring in HIV-positive individuals, characterized by reduced Shannon entropy and significant correlations between classifier probability and repertoire concentration. These findings support a dual-layer model of serology in which the integration of pathogen-derived and host-derived peptides into a meta model encode antigen specificity, whereas host-reactive signatures reflect systemic immune topology. Distinguishing diagnostic ranking from immune-state encoding provides a conceptual framework for multi-layer serological diagnostics.

immunology↗

bioRxiv2026

High-density peptide arrays detect tuberculosis through immune remodeling, not only antigen recognition alone

Serological diagnostics for tuberculosis rely on pathogen-derived antigens to detect infection-specific antibodies. Whether chronic TB infection also reshapes the global topology of the antibody repertoire remains largely unexplored. Here we profile serum antibody binding across 6,936 peptides in 105 individuals from three countries using two complementary libraries: Mycobacterium tuberculosis peptides (TBC) and a resemblance-ranking library representing the human self-proteome (RRL). We construct a five-dimensional immune state vector from distributional binding properties and map individual sera into an immune phase space. A remodeling classifier achieves virtually identical performance on pathogen-derived and host-derived peptides (AUC 0.63-0.73), demonstrating that the diagnostic signal arises from global repertoire restructuring rather than antigen-specific recognition. HIV co-infection partially masks this signal; restricting analysis to HIV-negative individuals increases AUC to 0.73 (permutation p = 0.005) and enables detection of smear-negative TB (AUC = 0.83, specificity 0.95 with three peptides). Phase-space projections reveal that TB severity maps onto a continuous remodeling gradient, with smear-negative patients occupying intermediate positions between healthy controls and smear-positive cases. These findings position high-density peptide arrays as sensors of antibody repertoire topology, enabling detection of chronic immune states beyond antigen-specific recognition.

immunology↗

bioRxiv2024

Making the effect visible - OX40 targeting nanobodies for in vivo imaging of activated T cells

PurposeHuman OX40 (hOX40/CD134), a member of the TNF receptor superfamily, is mainly expressed on activated T lymphocytes. Triggered by its ligand OX40L (CD252), it provides costimulatory signals that support the differentiation, proliferation and long-term survival of T cells. Besides being a relevant therapeutic target, hOX40 is also an important biomarker for monitoring the presence or infiltration of activated T cells within the tumor microenvironment (TME), the inflammatory microenvironment (IME) in immune-mediated diseases (IMIDs) and the lymphatic organs. Here, we developed novel single domain antibodies (nanobodies, Nbs) targeting hOX40 to monitor the activation status of T cells by in vivo molecular imaging. MethodsNbs against hOX40 (hOX40-Nbs) were selected from an immunized Nb-library by phage display. The identified hOX40-Nbs were characterized in vitro, including determination of their specificity, affinity, stability, epitope recognition and their impact on OX40 signaling and T cell function. A lead candidate was site-specifically conjugated with a fluorophore via sortagging and applied for noninvasive in vivo optical imaging (OI) of hOX40-expressing cells in a xenograft mouse model. ResultsOur selection campaign revealed four unique Nbs that exhibit strong binding affinities and high stabilities under physiological conditions. Epitope binning and domain mapping indicated the targeting of at least two different epitopes on hOX40. When analyzing their impact on OX40 signaling, an agonistic effect was excluded for all validated Nbs. Incubation of activated T cells with hOX40-Nbs did not affect cell viability or proliferation patterns, whereas differences in cytokine release were observed. In vivo OI with a fluorophore-conjugated lead candidate in experimental mice with hOX40-expressing xenografts demonstrated its specificity and functionality as an imaging probe. ConclusionConsidering the need for advanced probes for noninvasive in vivo monitoring of T cell activation dynamics, we propose, that our hOX40-Nbs have a great potential as imaging probes for noninvasive and longitudinal in vivo diagnostics. Quantification of OX40+ T cells in TME or IME will provide crucial insights into the activation state of infiltrating T cells, offering a valuable biomarker for assessing immune responses, predicting treatment efficacy, and guiding personalized immunotherapy strategies in patients with cancer or IMIDs.

immunology↗

bioRxiv2023

Development and validation of a respiratory syncytial virus multiplex immunoassay

Respiratory syncytial virus (RSV) is one of the leading causes of severe respiratory disease in infants and adults. RSV exists as two subtypes A and B, which co-circulate throughout the season, although one will usually become dominant. While vaccines and monoclonal therapeutic antibodies either are or will shortly become available, correlates of protection remain unclear. For this purpose, we developed an RSV multiplex immunoassay that analyses antibody titers towards the post-F, Nucleoprotein, and a diverse mix of G proteins. Technical and clinical validation showed outstanding performance, while methodological developments enabled identification of the subtype of previous infections through use of the diverse G proteins for approximately 50% of samples. As a proof of concept to show the suitability of the assay in serosurveillance studies, we then evaluated titer decay and age- dependent antibody responses within population cohorts. Overall, the developed assay shows robust performance, is scalable, provides additional information on infection subtype, and is therefore ideally suited to be used in future population cohort studies. ImportanceAlthough respiratory syncytial virus (RSV) is endemic and re-infections are common and harmless to the majority of the population, it is a leading cause of hospitalization in young children, the elderly, or immunocompromised individuals. A better characterization of RSV immunology and spreading dynamics is thus critical for preparedness, especially when interventions aiming to mitigate other diseases (e.g., COVID-19) disturb its endemic cycles. This requires high-throughput information-dense assays. We therefore developed a bead-based multiplex immunoassay that allows measurements of antibodies against multiple RSV antigens simultaneously. We identified antibodies which were strong indicators of previous infection, while others allowed identification of the subtype of the previous infection. The assay itself was shown to be robust and scalable, making it ideal for to keep track of the temporal variation RSV immunity profiles within the population.

immunology↗

bioRxiv2022

LRRK2-G2019S SYNERGIZES WITH AGEING AND LOW-GRADE INFLAMMATION TO PROMOTE GUT AND PERIPHERAL IMMUNE CELL ACTIVATION THAT PRECEDE NIGROSTRIATAL DEGENERATION

BackgroundMutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most frequent cause of familial Parkinsons disease (PD). The incomplete penetrance of LRRK2 mutations suggest that additional hits are required for disease onset. We hypothesized that chronic low-grade inflammation interacts with LRRK2 G2019S, the most frequent PD-associated mutation, to activate peripheral and central immune reactions and drive age-dependent neurodegeneration. Methods and ResultsWe exposed wild-type and LRRK2 G2019S mice to a low chronic dose of lipopolysaccharide, and we performed a longitudinal analysis of central and peripheral immune reactions and neurodegeneration. Low-dose inflammation triggered nigrostriatal degeneration, macrophage/monocyte brain infiltration, and astro-/microgliosis. LRRK2 G2019S mice showed an early dysregulation of peripheral cytokines, increased CD4+ T-cell infiltration and -synuclein aggregation in the colon. Interestingly, peripheral immune activation and colonic -synuclein aggregation precede astro-/microgliosis and neurodegeneration. ConclusionsOur study suggests an early role of the peripheral immune system and the gut in LRRK2 PD and provides a novel model to study early therapeutic immune targets and biomarkers.

neuroscience↗

bioRxiv2021

A broadly neutralizing biparatopic Nanobody protects mice from lethal challenge with SARS-CoV-2 variants of concern

The ongoing COVID-19 pandemic and the frequent emergence of new SARS-CoV-2 variants of concern (VOCs), requires continued development of fast and effective therapeutics. Recently, we identified high-affinity neutralizing nanobodies (Nb) specific for the receptor-binding domain (RBD) of SARS-CoV-2, which are now being used as biparatopic Nbs (bipNbs) to investigate their potential as future drug candidates. Following detailed in vitro characterization, we chose NM1267 as the most promising candidate showing high affinity binding to several recently described SARS-CoV-2 VOCs and strong neutralizing capacity against a patient isolate of B.1.351 (Beta). To assess if bipNb NM1267 confers protection against SARS-CoV-2 infection in vivo, human ACE2 transgenic mice were treated by intranasal route before infection with a lethal dose of SARS-CoV-2. NM1267-treated mice showed significantly reduced disease progression, increased survival rates and secreted less infectious virus via their nostrils. Histopathological analyses and in situ hybridization further revealed a drastically reduced viral load and inflammatory response in lungs of NM1267-treated mice. These data suggest, that bipNb NM1267 is a broadly active and easily applicable drug candidate against a variety of emerging SARS-CoV-2 VOCs.

biochemistry↗

bioRxiv2021

Single-domain antibodies for targeting, detection and in vivo imaging of human CD4+ cells

The advancement of new immunotherapies necessitates appropriate probes to monitor the presence and distribution of distinct immune cell populations. Considering the key role of CD4+ T cells in regulating immunological processes, we generated novel single-domain antibodies (nanobodies, Nbs) that specifically recognize human CD4. After in depth analysis of their binding properties, recognized epitopes, and effects on T cell proliferation, activation and cytokine release, we selected CD4 Nbs that did not interfere with crucial T cell processes in vitro and converted them into immune tracers for non-invasive molecular imaging. By optical imaging, we demonstrate the ability of a high-affinity CD4-Nb to specifically visualize CD4+ cells in vivo using a xenograft model. Furthermore, time-resolved immune positron emission tomography (immunoPET) of a human CD4 knock-in mouse model showed rapid accumulation of 64Cu-radiolabeled CD4-Nb in CD4+ T cell-rich tissues. We propose that the CD4 Nbs presented here could serve as versatile probes for stratifying patients and monitoring individual immune responses during personalized immunotherapy in both cancer and inflammatory diseases.

immunology↗

bioRxiv2020

NeutrobodyPlex - Nanobodies to monitor a SARS-CoV-2 neutralizing immune response

As the COVID-19 pandemic escalates, the need for effective vaccination programs, therapeutic intervention, and diagnostic tools increases. Here, we identified 11 unique nanobodies (Nbs) specific for the SARS-CoV-2 spike receptor-binding domain (RBD) of which 8 Nbs potently inhibit the interaction of RBD with angiotensin-converting enzyme 2 (ACE2) as the major viral docking site. Following a detailed epitope determination and characterization of the binding mode by structural analysis, we constructed a hetero-bivalent Nb targeting two different epitopes within the RBD:ACE2 interface. This resulted in a high-affinity binder with a viral neutralization efficacy in the picomolar range. Using the bivalent Nb as a surrogate, we established a competitive multiplex binding assay ("NeutrobodyPlex") for detailed analysis of the presence and performance of neutralizing RBD-binding antibodies in the serum of convalescent or vaccinated patients. As demonstrated, the NeutrobodyPlex enables high-throughput screening and detailed analysis of neutralizing immune responses in infected or vaccinated individuals, helping to monitor immune status or guide vaccine design. This approach is easily transferrable to diagnostic laboratories worldwide.

immunology↗

bioRxiv2020

Interferon-γ signaling synergizes with LRRK2 in human neurons and microglia

Increasing evidence suggests a role for interferons (IFNs) in neurodegeneration. Parkinsons disease (PD) associated kinase LRRK2 has been implicated in IFN type II (IFN) response in infections and nigral neuronal loss. However, whether and how LRRK2 synergizes with IFN-{gamma} still remains unclear. Here, we employed dopaminergic (DA) neurons and microglia differentiated from patient induced pluripotent stem cells to unravel the role of IFN-{gamma} in LRRK2-PD. We show that IFN-{gamma} induces LRRK2 expression in both DA neurons and microglial cells. LRRK2-G2019S, the most common PD-associated mutation, sensitizes DA neurons to IFN-{gamma} by decreasing AKT phosphorylation. IFN-{gamma} suppresses NFAT activity in both neurons and microglia and synergistically enhances LRRK2-induced defects of NFAT activation. Furthermore, LRRK2-G2019S negatively regulates NFAT via calcium and microtubule dynamics. Importantly, we uncover functional consequences of the reduction of NFAT activity in both cell types, namely defects of neurite elongation and alteration of microglial activation profile and motility. We propose that synergistic IFN-{gamma}/LRRK2 activation serves as a direct link between inflammation and neurodegeneration in PD.

neuroscience↗

bioRxiv2018

Complexes of RNA and the antimicrobial peptide, LL37, trigger TLR-mediated cytokine release from psoriasis neutrophils

Psoriasis is an inflammatory autoimmune disease characterized by skin lesions showing strong neutrophil (PMN) infiltration and high levels of the antimicrobial peptide, LL37, but the role of PMNs in this context remains unclear. We here show that primary human PMNs, especially PMNs from psoriasis patients, not only respond via TLR8 to human and bacterial RNA in complexed with LL37 by cytokine-, chemokine- and neutrophil extracellular trap (NET)-release; they also actively release additional RNA and LL37 in response to stimulation by the same complex and both RNA and LL37 were found to be highly abundant in psoriatic skin. Moreover, RNA-LL37-induced NETs propagated PMN activation and could thus fuel a PMN-mediated and self-sustaining inflammatory loop that may represent an unexpected early initiator or amplifying event in psoriasis. Given that TLR inhibitory oligodeoxynucleotides prevented the cytokine production and NETosis of PMNs by RNA-LL37 complexes in vitro, our study also highlights TLR blockade as a potential therapeutic intervention strategy in psoriasis. SummaryHuman and bacterial RNA in complex with LL37 activates neutrophils via TLR8 to release cytokines, chemokines and neutrophil extracellular traps (NETs). NETs and neutrophil-rich areas in psoriatic skin contain RNA and LL37, suggesting RNA-LL37 may fuel a PMN-mediated and self-sustaining inflammatory cycle in psoriasis.

immunology↗