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McDaniel, J. R.

Publications and source records attributed to McDaniel, J. R..

5 recordsLinked to original sources

Imprinted antibody lineages can persist for half a century and dominate cross-neutralizing recall responses to poliovirus

Humoral immunity depends on a dynamic interplay between circulating polyclonal IgG antibodies and long-lived memory B cells (MBC). To elucidate this relationship, we integrated B-cell receptor sequencing with plasma IgG immunoproteomics to identify and quantify the recall response (plasma IgG and MBC) to inactivated poliovirus vaccine (IPV) in eight adults, 24-55 years after their childhood immunization. IPV immunization elicited highly skewed plasma IgG recall repertoires, dominated by a small subset ([~]8%) of total antibody lineages that were detectable prior to boosting (i.e., "pre-existing"). These IgG lineages spiked logarithmically in abundance ([~]102-104 fold-increase) and potently cross-neutralized multiple PV serotypes in vitro (titers [≥] 1:105). Notably, these dominant plasma IgG lineages were clonally linked to class-switched MBCs that circulated in blood 21 days post-boost and bore heavily mutated VH and VL variable region genes. Importantly, IPV-primed ex vivo B-cell cultures (MIMIC, Modular IMmune In vitro Construct) yielded clonal expansions that mirrored the dominant post-boost plasma IgG lineages in vivo, providing an in vitro mechanistic correlate of recall immunity. Together these findings demonstrate a decades-long interconnectivity between persistent MBC clones and the serological IgG repertoire. They further highlight the central role of immunological imprinting, whereby cross-reactive MBC clones--originally primed in childhood--can be reactivated to dominate the circulating IgG recall response more than 50 years after initial exposure.

immunology↗

Repertoire, function, and structure of serological antibodies induced by the R21/Matrix-M malaria vaccine

The World Health Organization recently recommended the programmatic use of R21/Matrix-M vaccine for Plasmodium falciparum malaria prevention in children living in malaria-endemic areas. To determine its effects on humoral immunity, we conducted a proteomic analysis of polyclonal IgG antibodies directed against the NANP tetrapeptide of the circumsporozoite protein (CSP) which comprises the vaccines core immunogen. In ten malaria-naive adult volunteers, R21/Matrix-M induced polarized IgG anti-NANP repertoires, heavily skewed for IGHV3-30/3-33 genes bearing minimal somatic mutation, which remained static in composition following a controlled human malaria infection challenge. Notably, these vaccine-generated antibodies cross-reacted with another protective CSP epitope, the N-terminal junction region, despite its absence from the R21 construct. NANP-specific IGHV3-30/3-33 monoclonal antibodies mined from polyclonal IgG repertoires blocked sporozoite invasion in vitro and prevented parasitemia in vivo. Overall, R21/Matrix-M elicits polarized, minimally mutated, polyclonal IgG responses that can target multiple protective CSP epitopes, offering molecular insight into the serological basis for its demonstrated efficacy against P. falciparum malaria.

immunology↗

Prevalent, protective, and convergent IgG recognition of SARS-CoV-2 non-RBD spike epitopes in COVID-19 convalescent plasma

Although humoral immunity is essential for control of SARS-CoV-2, the molecular composition, binding epitopes and effector functions of the immunoglobulin G (IgG) antibodies that circulate in blood plasma following infection are unknown. Proteomic deconvolution of the circulating IgG repertoire (Ig-Seq1) to the spike ectodomain (S-ECD2) in four convalescent study subjects revealed that the plasma response is oligoclonal and directed predominantly (>80%) to S-ECD epitopes that lie outside the receptor binding domain (RBD). When comparing antibodies directed to either the RBD, the N-terminal domain (NTD) or the S2 subunit (S2) in one subject, just four IgG lineages (1 anti-S2, 2 anti-NTD and 1 anti-RBD) accounted for 93.5% of the repertoire. Although the anti-RBD and one of the anti-NTD antibodies were equally potently neutralizing in vitro, we nonetheless found that the anti-NTD antibody was sufficient for protection to lethal viral challenge, either alone or in combination as a cocktail where it dominated the effect of the other plasma antibodies. We identified in vivo protective plasma anti-NTD antibodies in 3/4 subjects analyzed and discovered a shared class of antibodies targeting the NTD that utilize unmutated or near-germline IGHV1-24, the most electronegative IGHV gene in the human genome. Structural analysis revealed that binding to NTD is dominated by interactions with the heavy chain, accounting for 89% of the entire interfacial area, with germline residues uniquely encoded by IGHV1-24 contributing 20% (149 [A]2). Together with recent reports of germline IGHV1-24 antibodies isolated by B-cell cloning3,4 our data reveal a class of shared IgG antibodies that are readily observed in convalescent plasma and underscore the role of NTD-directed antibodies in protection against SARS-CoV-2 infection.

immunology↗

Decoding P300 Variability using Convolutional Neural Networks

Deep convolutional neural networks (CNN) have previously been shown to be useful tools for signal decoding and analysis in a variety of complex domains, such as image processing and speech recognition. By learning from large amounts of data, the representations encoded by these deep networks are often invariant to moderate changes in the underlying feature spaces. Recently, we proposed a CNN architecture that could be applied to electroencephalogram (EEG) decoding and analysis. In this article, we train our CNN model using data from prior experiments in order to later decode the P300 evoked response from an unseen, hold-out experiment. We analyze the CNN output as a function of the underlying variability in the P300 response and demonstrate that the CNN output is sensitive to the experiment-induced changes in the neural response. We then assess the utility of our approach as a means of improving the overall signal-to-noise ratio in the EEG record. Finally, we show an example of how CNN-based decoding can be applied to the analysis of complex data.

neuroscience↗

Identification of Tumor-Reactive B Cells and Systemic IgG in Breast Cancer Based on Clonal Frequency in the Sentinel Lymph Node

A better understanding of antitumor immune responses is key to advancing the field of cancer immunotherapy. Endogenous immunity in cancer patients, such as circulating anticancer antibodies or tumor-reactive B cells, has been historically yet incompletely described. Here, we demonstrate that tumor-draining (sentinel) lymph node (SN) is a rich source for tumor-reactive B cells that give rise to systemic IgG anticancer antibodies circulating in the bloodstream of breast cancer patients. Using a synergistic combination of high-throughput B-cell sequencing and quantitative immunoproteomics, we describe the prospective identification of tumor-reactive SN B cells (based on clonal frequency) and also demonstrate an unequivocal link between affinity-matured expanded B-cell clones in the SN and antitumor IgG in the blood. This technology could facilitate the discovery of antitumor antibody therapeutics and conceivably identify novel tumor antigens. Lastly, these findings highlight the unique and specialized niche the SN can fill in the advancement of cancer immunotherapy.\n\nSIGNIFICANCEUsing high-throughput molecular cloning and antibody proteomics to study coordinated antitumor immunity in breast cancer patients, we simultaneously demonstrate that the sentinel lymph node is a localized source of expanded antitumor B cells undergoing affinity maturation and that their secreted antibodies are abundant as systemic IgG circulating in blood.

immunology↗