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Moore, C.

Publications and source records attributed to Moore, C..

At least 37 records · Page 2Linked to original sources

The alternative polyadenylation regulator CFIm25 promotes macrophage differentiation and activates the NF-κβ pathway

Macrophages are required for our bodys development and tissue repair and protect against microbial attacks. We previously reported a crucial role for regulation of mRNA 3-end cleavage and polyadenylation (C/P) in monocyte to macrophage differentiation. The CFIm25 subunit of the C/P complex showed a striking increase upon differentiation of monocytes with Phorbol Myristate Acetate, suggesting that it promotes this process. To test this hypothesis, CFIm25 was overexpressed in two different monocytic cell lines, followed by differentiation. Both cell lines showed a significant increase in macrophage characteristics and an earlier slowing of the cell cycle. In contrast, depletion of CFIm25 hindered differentiation. Cell cycle slowing upon CFIm25 overexpression was consistent with a greater decrease in the proliferation markers PCNA and cyclin D1, coupled with increased 3UTR lengthening of cyclin D1 mRNA. Since choice of other poly(A) sites could be affected by manipulating CFIm25, we identified additional genes with altered use of poly(A) sites during differentiation and examined how this changed upon CFIm25 overexpression. The mRNAs of positive regulators of NF-{kappa}B signaling, TAB2 and TBL1XR1, and NFKB1, which encodes the NF-{kappa}B p50 precursor, underwent 3UTR shortening that was associated with increased protein expression compared to the control. Cells overexpressing CFIm25 also showed elevated levels of phosphorylated NF-{kappa}B-p65 and the NF-{kappa}B targets p21, Bcl-XL, ICAM1 and TNF- at an earlier time and greater resistance to NF-{kappa}B chemical inhibition. In conclusion, our study supports a model in which CFIm25 accelerates the monocyte to macrophage transition by promoting alternative polyadenylation events which lead to activation of the NF-{kappa}B pathway.

molecular biology↗

FindingNemo: A Toolkit for DNA Extraction, Library Preparation and Purification for Ultra Long Nanopore Sequencing

Since the advent of long read sequencing, achieving longer read lengths has been a key goal for many users. Ultra-long read sets (N50 [≥] 100 kb) produced from Oxford Nanopore sequencers have improved genome assemblies in recent years. However, despite progress in extraction protocols and library preparation methods, ultra-long sequencing remains challenging for many sample types. Here we compare various methods and introduce the FindingNemo protocol that: (1) optimises ultra-high molecular weight (UHMW) DNA extraction and library clean-up by using glass beads and Hexamminecobalt(III) chloride (CoHex), (2) can deliver high ultra-long sequencing yield of >20 Gb of reads from a single MinION flow cell or >100 Gb from PromethION devices (R9.4 to R10.4 pore variants), and (3) is scalable to using fewer input cells or lower DNA amounts, with extraction to sequencing possible in a single working day. By comparison, we show this protocol is superior to previous ones due to precise determination of input DNA quantity and quality by cell count, sample dilution and homogenization approaches.

genomics↗

An ecological, phenotypic and genomic survey of duckweeds with their associated aquatic environments in the United Kingdom

The duckweeds feature global distributions and diverse applications in phytoremediation and nutrition, as well as use in fundamental studies of development. Existing collections have minimal environmental data linked to natural habitats. Thus, there is a lack of understanding of natural variation in the context of native habitats. Here, a novel collection of 124 duckweed accessions from 115 sites across the United Kingdom were characterised by genome sequencing and ionomics. In nutrient-replete conditions all accessions hyperaccumulated P, K, Mg and Ca. Local but not large-scale associations were revealed between elemental composition of duckweed in common, replete conditions and native water profiles. Lemna minor was the most prevalent species in the UK, with a closely related hybrid L. japonica frequently found in waters with higher micronutrient concentrations. Invasive L. minuta was common in the southern and midland regions, but restricted in Scotland. Lemna accessions accumulated heavy metal contaminants typically together with macronutrients, suggesting phytoremediation potential, but some limitations as food. Furthermore, monitoring the ecological interactions between native, hybrid and invasive Lemna species should be ongoing in the interest of biodiversity.

ecology↗

Spatial proteomic analysis of a lung cancer model reveals regulatory T cells attenuate KRAS-G12C inhibitor-induced immune responses

We recently showed that lung tumor specific KRAS-G12C inhibition causes remodelling of the tumor immune microenvironment from cold to hot. As a result, KRAS-G12C inhibition is able to synergise with anti-PD-1 treatment, but only in tumor models that were already moderately responsive to immune checkpoint blockade at baseline. To investigate mechanisms that restrain immunotherapy sensitivity in non-responsive tumors, we used multiplex imaging mass cytometry to explore spatial patterns in the tumor microenvironment of the highly immune evasive KRAS mutant murine Lewis Lung Cancer model. Clustering of close neighbour information per cell allowed characterisation of spatial patterns or communities in the tissue. We identified a community harbouring features of localised T-cell activation, where CD4+ and CD8+ T cells and dendritic cells were gathered together. KRAS-G12C inhibition led to increased expression of PD-1 on T cells, CXCL9 expression by dendritic cells, together with increased proliferation and potential cytotoxicity of CD8+ T cells, indicating an effector response. However, we also observed a high incidence of regulatory T cells (Tregs) within this community, which had frequent contact with effector T cells, suggesting that Tregs may be able to dampen anti-tumoral immune responses following KRAS-G12C inhibition. Similar communities were detected in human lung adenocarcinoma clinical samples. Depleting Tregs in vivo with anti-CTLA-4 antibody rescued the anti-tumor immune response and led to enhanced tumor control in combination with anti-PD-1 and KRAS-G12C inhibitor. We therefore propose use of KRAS-G12C inhibitor in combination with Treg depletion as a therapeutic opportunity that increases anti-tumoral immune responses and initiates tumor regression. One sentence summarySpatial analysis identified regulatory T cells as potential source of local T cell repression, mediating resistance to KRAS-G12Ci and anti-PD1 therapy.

cancer biology↗

How clinically relevant are prostate cancer cell lines? A comprehensive characterisation and multiomics comparison.

Cell line experiments arguably remain the most used tool in preclinical cancer research, despite their limitations. With almost 95% drugs entering human trials failing, and up to 90% preclinical research failing before even being tested in humans, we must shift the pre-clinical paradigm. A range of in silico, in vitro, in vivo and ex vivo approaches are gaining popularity, with the aim of potentially replacing cell line use. However, we cannot ignore the plethora of historical data from cell lines, nor write off their future use- especially within advanced bioengineered models. Therefore, we must question if and how cell lines hold clinical relevance. This study evaluates the clinical characteristics of 46 prostate cancer cell lines against worldwide data and investigates the biological features of seven cell lines in depth, comparing them to over 10,000 well characterised human cases from 24 studies in nine countries. Clinical features compared included age, ethnicity, Gleason grade, cancer type, treatment history and multiomics variables included mutations, copy number alterations, structural variants, microsatellite instability, mRNA and protein expression, and tumour mutational burden. We found that the most used cell lines accurately represent a minute proportion of prostate cancer patients. Furthermore, we recommend a pipeline for tailoring selection of clinically relevant cell lines with the ultimate aim of increasing the scientific methodology behind choosing a cell line.

cancer biology↗

Combining RASG12C(ON) inhibitor with SHP2 inhibition sensitises immune excluded lung tumours to immune checkpoint blockade: a strategy for turning cold tumours hot

Mutant selective drugs targeting the inactive, GDP-bound form of KRASG12C have been approved for use in lung cancer, but responses are short-lived due to rapid development of resistance. In this study we use a novel covalent tri-complex inhibitor, RMC-4998, that targets RASG12C in its active, GTP-bound form to investigate treatment of KRAS mutant lung cancer in various immune competent mouse models. While this RASG12C(ON) inhibitor was more potent than the KRASG12C(OFF) inhibitor adagrasib, rapid pathway reactivation was still observed. This could be delayed using combined treatment with a SHP2 inhibitor, RMC-4550, which not only impacted RAS pathway signalling within the tumour cells but also remodelled the tumour microenvironment (TME) to be less immunosuppressive and promoted interferon responses. In an inflamed, "hot", mouse model of lung cancer, RASG12C(ON) and SHP2 inhibitors in combination drive durable responses by suppressing tumour relapse and inducing development of immune memory, which can also be induced by combination of RASG12C(ON) and PD-1 inhibitors. In contrast, in an immune excluded, "cold", mouse model of lung cancer, combined RASG12C(ON) and SHP2 inhibition does not cause durable responses, but does sensitise tumours to immune checkpoint blockade, enabling efficient tumour rejection, accompanied by significant TME reorganization, including depletion of immunosuppressive innate immune cells and recruitment and activation of T and NK cells. These preclinical results demonstrate the potential of the combination of RASG12C(ON) inhibitors with SHP2 inhibitors to sensitize anti-PD-1 refractory tumours to immune checkpoint blockade by stimulating anti-tumour immunity as well as by targeting KRAS-driven proliferation in tumour cells.

cancer biology↗

Alpha-synuclein regulates nucleolar DNA double-strand break repair in melanoma

Although an increased risk of the skin cancer melanoma in people with Parkinsons Disease (PD) has been shown in multiple studies, the mechanisms involved are poorly understood, but increased expression of the PD-associated protein alpha-synuclein (Syn) in melanoma cells may be important. Our previous work suggests that Syn can facilitate DNA double-strand break (DSB) repair, promoting genomic stability. We now show that Syn is preferentially enriched within the nucleolus in the SK-MEL28 melanoma cell line, where it colocalizes with DNA damage markers and DSBs. Inducing DSBs specifically within nucleolar ribosomal DNA (rDNA) increases Syn levels near sites of damage. Syn knockout increases DNA damage within the nucleolus at baseline, after specific rDNA DSB induction, and prolongs the rate of recovery from this induced damage. Syn is important downstream of ATM signaling to facilitate 53BP1 recruitment to DSBs, reducing micronuclei formation and promoting cellular proliferation, migration, and invasion.

cell biology↗

Single-cell transcriptomics reveals heterogenous thymic dendritic cell subsets with distinct functions and requirements for thymocyte-regulated crosstalk

Dendritic cells are essential for establishing thymic central tolerance; however, mechanisms supporting their homeostasis and activation remain unresolved. Through single-cell transcriptomics and functional assays, we identify seven thymic conventional dendritic cell (cDC) subsets and discriminate their abilities to present self-antigens and induce regulatory T cells. Mice blocked at different stages of T-cell development reveal that CD4+ single-positive (SP) and CD8SP thymocytes differentially support homeostasis and activation of cDC1s versus cDC2s/plasmacytoid DCs (pDCs), respectively. CD8SPs indirectly support pDC survival and cDC2 thymic immigration, and they induce interferon signaling in cDCs, partly by promoting Type III interferon expression by medullary thymic epithelial cells (mTECs). In contrast, CD4SPs undergo cognate interactions with cDCs, inducing CD40 signaling required for activation of cDC1s. Activated cDC1s make non-redundant contributions to central tolerance. Altogether, this study comprehensively identifies distinct thymic DC subsets and elucidates requirements for crosstalk with thymocyte subsets that support their homeostasis, activation, and function.

immunology↗

A polydiolcitrate-MoS2 composite for 3D printing Radio-opaque, Bioresorbable Vascular Scaffolds

Implantable polymeric biodegradable devices, such as biodegradable vascular stents or scaffolds, cannot be fully visualized using standard X-ray-based techniques, compromising their performance due to malposition after deployment. To address this challenge, we describe composites of methacrylated poly(1,12 dodecamethylene citrate) (mPDC) and MoS2 nanosheets to fabricate novel X-ray visible radiopaque and photocurable liquid polymer-ceramic composite (mPDC-MoS2). The composite was used as an ink with micro continuous liquid interface production (CLIP) to fabricate bioresorbable vascular scaffolds (BVS). Prints exhibited excellent crimping and expansion mechanics without strut failures and, importantly, required X-ray visibility in air and muscle tissue. Notably, MoS2 nanosheets displayed physical degradation over time in a PBS environment, indicating the potential for producing bioresorbable devices. mPDC-MoS2 is a promising bioresorbable X-ray-visible composite material suitable for 3D printing medical devices, particularly vascular scaffolds or stents, that require non-invasive X-ray-based monitoring techniques for implantation and evaluation. This innovative composite system holds significant promise for the development of biocompatible and highly visible medical implants, potentially enhancing patient outcomes and reducing medical complications. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=124 SRC="FIGDIR/small/564364v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@58cb6aorg.highwire.dtl.DTLVardef@192d2b1org.highwire.dtl.DTLVardef@4699a3org.highwire.dtl.DTLVardef@110d7f8_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Impact of whole-genome duplications on structural variant evolution in the plant genus Cochlearia

Polyploidy, the result of whole-genome duplication (WGD), is a major driver of eukaryote evolution. All angiosperms have undergone ancient WGDs, and today stable polyploids account for a substantial portion of both wild and domesticated plant species. Despite its centrality in evolution, WGD is a hugely disruptive mutation, and we still lack a clear understanding of its fitness consequences. Here, we study whether WGD results in greater diversity of genomic structural variants (SVs) and how this influences evolutionary dynamics in nature. Using a set of long-read sequenced samples from the plant genus Cochlearia (Brassicaceae), which contains diploids and a recent ploidy series up to octoploid, we show that masking of recessive mutations due to WGD has led to a substantial and progressive accumulation of genic SVs across four ploidy levels. Such SVs likely constitute a genetic load and thus reduce the adaptive potential of polyploid populations. However, this SV accumulation also provides a rich pool of standing genetic variation upon which selection may act in novel environments. By constructing a graph-based pangenome for Cochlearia, we identify SVs in hundreds of samples and study the genomic basis of environmental adaptation. We find putatively beneficial SVs involved in pathogen resistance, root development, and salt tolerance, many of which are unique to polyploids. Finally, we explore the adaptive landscapes of SVs and SNPs, identify geographical regions where SVs make novel contributions to adaptive variation, and predict that the role of SVs in environmental adaptation increases due to rapid climate change.

evolutionary biology↗

Kinetochore and ionomic adaptation to whole genome duplication

Transforming genomic and cellular landscapes in a single generation, whole genome duplication (WGD) brings fundamental challenges, but is also associated with diversification. How is WGD tolerated, and what processes commonly evolve to stabilize the resulting polyploid? Here we study this in Cochlearia spp., which have experienced multiple WGDs in the last 300,000 years. We first generate a chromosome-scale genome and sequence 113 individuals from 33 diploid, tetraploid, hexaploid, and outgroup populations. We detect the clearest post-WGD selection signatures in functionally interacting kinetochore components and ion transporters. We structurally model these derived selected alleles, identifying striking WGD-relevant functional variation, and then compare these results to independent recent post-WGD selection in Arabidopsis arenosa and Cardamine amara. Most prominent in these results is genetic evidence of at least four functionally interacting kinetochore complex subunits in adaptation to WGD at the centromere among our very top selective sweep outliers. In addition, some of the same biological processes evolve in all three WGDs, but specific genes recruited are flexible. This points to a polygenic basis for modifying systems that control the kinetochore, meiotic crossover number, DNA repair, ion homeostasis, and cell cycle. Given that DNA management (especially repair) is the most salient category with the strongest selection signal, we speculate that the generation rate of structural genomic variants may be altered by WGD in young polyploids, contributing to their occasionally spectacular adaptability observed across kingdoms. Significance StatementWhole-genome duplication (WGD) occurs in all kingdoms and is linked to adaptation, speciation, domestication, and even cancer outcome. But WGD is a shock to the system, and commonly disrupts cell division due to increased DNA management burden and transformed cell physiology. Nevertheless, the hopeful monster that survives WGD is special, occasionally experiencing runaway success. Why do some thrive but others die? Here we introduce a powerful new model, Cochlearia, which has benefitted from multiple WGDs, and we provide the first genetic evidence of rapid adaptation of functionally interacting components of the cell division machinery, the kinetochore. We also compare which processes and genes evolve to stabilize the new polyploid in three independent cases and highlight common mechanisms.

evolutionary biology↗

In vivo CRISPR screen identifies KRAS-induced COX-2 as a driver of immune evasion and immunotherapy resistance in lung cancer

Oncogenic KRAS impairs anti-tumour immune responses, but effective strategies to combine KRAS inhibitors and immunotherapies have so far proven elusive. In vivo CRISPR-Cas9 screening in an immunogenic murine lung cancer model identifies mechanisms by which oncogenic KRAS promotes immune evasion, most notably expression of immunosuppressive cyclooxygenase-2 (COX-2) in cancer cells. Oncogenic KRAS was a potent inducer of COX-2 in both mouse and human lung cancer which was suppressed using KRAS inhibitors. COX-2 acting via prostaglandin E2 (PGE2) promotes resistance to immune checkpoint blockade (ICB) in both mouse and human lung adenocarcinoma. Targeting COX-2/PGE2 remodelled the tumour microenvironment by inducing pro-inflammatory polarisation of myeloid cells and influx of activated cytotoxic CD8+ T cells, which increased the efficacy of ICB. Restoration of COX-2 expression contributed to tumour relapse after prolonged KRAS inhibition. We propose testing COX-2/PGE2 pathway inhibitors in combination with KRAS G12C inhibition or ICB in patients with KRAS-mutant lung cancer.

cancer biology↗

B cell repertoire in children with skin barrier dysfunction supports altered IgE maturation associated with allergic food sensitization

IgE B cells produce antibodies responsible for the inappropriate specificity seen in allergic disease. In this study, we sequence antibody gene repertoires from a large, well-characterized early life cohort at risk for developing food allergy. We found that food allergen sensitization was associated with lower IgE mutation frequencies that was abrogated in children living with a pet dog, suggesting potential molecular mechanisms underlying the hygiene hypothesis (i.e., protective effects of pet ownership and non-antiseptic environs reported for allergic disease). We also observed increased IgE diversity and increased isotype-switching to IgE, suggesting that B cell development is altered in those with food allergen sensitizations relative to those without. IgE diversity was even more extreme in subjects who were highly likely to be peanut allergic. Unlike food antigen sensitization, we detected no effect of aeroallergen sensitization on IgE mutation levels and diversity. Consistent patterns of antibody rearrangement were associated with food allergen sensitization. These results have important implications for the allergic response driven by mast cells and basophils and the underlying drivers of the atopic march.

immunology↗

Identification of regulatory elements in primary sensory neurons involved in neuropathic pain

Chronic pain is a significant public health issue that is often refractory to existing therapies. Here we use a multiomic approach to identify cis-regulatory elements that show differential chromatin accessibility, and reveal transcription factor (TF) binding motifs with functional regulation in the dorsal root ganglion (DRG), which contain cell bodies of primary sensory neurons, after nerve injury. We integrated RNA-seq to understand how differential chromatin accessibility after nerve injury may influence gene expression. Using TF protein arrays and chromatin immunoprecipitation-qPCR, we confirmed C/EBP{gamma} binding to a differentially accessible sequence and used RNA-seq to identify processes in which C/EBP{gamma} plays an important role. Our findings offer insights into TF motifs that are associated with chronic pain. These data show how interactions between chromatin landscapes and TF expression patterns may work together to determine gene expression programs in DRG neurons after nerve injury.

neuroscience↗

Lysosomal damage drives mitochondrial proteome remodelling and reprograms macrophage immunometabolism

Transient lysosomal damage after infection with cytosolic pathogens or silica crystals uptake results in protease leakage. Whether limited leakage of lysosomal contents into the cytosol affects the function of cytoplasmic organelles is unknown. Here, we show that sterile and non-sterile lysosomal damage triggers a cell death independent proteolytic remodelling of the mitochondrial proteome in macrophages. Mitochondrial metabolic reprogramming required lysosomal leakage of Cathepsin B and Cathepsin L and was independent of proteasome degradation and mitophagy. In a mouse model of endomembrane damage, metabolic analysis confirmed that in vivo, live lung macrophages that internalised crystals displayed impaired mitochondrial function and increased glycolytic and lipid metabolism. Single-cell RNA-sequencing analysis of bronchoalveolar lavage revealed that lysosomal damage skewed metabolic and immune responses primarily in CD36+/LIPA+ and Krt79+/Car4+ subsets of alveolar macrophages. Importantly, modulation of macrophage metabolism with 2-Deoxy- d- glucose and oxamate impacted the host response to Mycobacterium tuberculosis (Mtb) infection in an endomembrane damage dependent manner. This work uncovers a new inter-organelle communication pathway, providing a general mechanism by which macrophages undergo mitochondrial metabolic reprograming after endomembrane damage.

cell biology↗

Macrophage differentiation is marked by increased abundance of the mRNA 3' end processing machinery, altered poly(A) site usage, and sensitivity to the level of CstF64

Regulation of mRNA polyadenylation is important for response to external signals and differentiation in several cell types, and results in mRNA isoforms that vary in the amount of coding sequence or 3 UTR regulatory elements. However, its role in differentiation of monocytes to macrophages has not been investigated. Macrophages are key effectors of the innate immune system that help control infection and promote tissue-repair. However, overactivity of macrophages contributes to pathogenesis of many diseases. In this study, we show that macrophage differentiation is characterized by shortening and lengthening of mRNAs in relevant cellular pathways. The cleavage/polyadenylation (C/P) proteins increase during differentiation, suggesting a possible mechanism for the observed changes in poly(A) site usage. This was surprising since higher C/P protein levels correlate with higher proliferation rates in other systems, but monocytes stop dividing after induction of differentiation. Depletion of CstF64, a C/P protein and known regulator of polyadenylation efficiency, delayed macrophage marker expression, cell cycle exit, attachment, and acquisition of structural complexity, and impeded shortening of mRNAs with functions relevant to macrophage biology. Conversely, CstF64 overexpression increased use of promoter-proximal poly(A) sites and caused the appearance of differentiated phenotypes in the absence of induction. Our findings indicate that regulation of polyadenylation plays an important role in macrophage differentiation.

molecular biology↗

Genomic islands of divergence between Drosophila yakuba subspecies predominantly overlap with chromosomal inversions

During the early stages of local adaptation and speciation, genetic differences tend to accumulate at certain regions of the genome leading to the formation of genomic islands of divergence (GIDs). This pattern may be due to selection and/or difference in the rate of recombination. Here, we investigate the possible causes of GIDs in Drosophila yakuba mayottensis, and reconfirm using field collection its association with toxic noni (Morinda citrifolia) fruits on the Mayotte island. Population genomics revealed lack of genetic structure on the island and identified 20 GIDs distinguishing D. y. mayottensis from generalist mainland populations of D. y. yakuba. The GIDs were enriched with gene families involved in the metabolism of lipids, sugars, peptides and xenobiotics, suggesting a role in host shift. We assembled a new genome for D. y. mayottensis and identified five novel chromosomal inversions. Twelve GIDs ([~]72% of outlier windows) fell close to or within subspecies-specific inversions. However, three GIDs were in collinear, high recombining regions indicating strong signal of hard selective sweeps. Unlike D. y. mayottensis, D. sechellia, the only other noni-specialist, is homosequential with its generalist relatives. Thus, both selection and rearrangements shape GIDs and striking convergences can occur between species with distinct genomic architectures.

evolutionary biology↗

A unified peptide array platform for antibody epitope binning, mapping, specificity and predictive off-target binding

Therapeutic antibody efficacy is largely determined by the target epitope. In addition, off-target binding can result in unanticipated side-effects. Therefore, characterization of the epitope and binding specificity are critical in antibody discovery. Epitope binning provides low-resolution of an antibody epitope and is typically performed as a cross-blocking assay to group antibodies into overlapping or non-overlapping bins. Epitope mapping identifies the epitope with high resolution but requires low throughput methods. In addition to binning and mapping, there is a need for a scalable and predictive approach to reveal off-target binding early in antibody discovery to reduce the risk of in vivo side effects. Peptide microarrays are an information-rich platform for antibody characterization. However, the potential of peptide microarrays in early-stage antibody discovery has not been realized because they are not produced at the scale, quality and format needed for reliable high-throughput antibody characterization. A unified, peptide library platform for high-resolution antibody epitope binning, mapping and predictive off-target binding characterization is described here. This platform uses highly scalable array synthesis and photolithography to synthesize more than 3 million addressable peptides. These arrays conform to a microplate format and each synthesis is qualified with mass spectrometry. Using this platform, a scalable approach to early-stage epitope and specificity characterization, with prediction of off-target interaction(s), is demonstrated using a panel of anti-HER2 monoclonal antibodies. This study highlights the prospect of this platform to improve antibody discovery productivity by generating epitope and specificity information much earlier with potentially hundreds of antibody clones.

bioengineering↗