Logic-gated antibody pairs that selectively act on cells co-expressing two antigens

Understanding IgM Structure and Biology to Engineer New Antibody Therapeutics

Immunoglobulin M (IgM) antibodies are an essential and conserved part of adaptive immunity. IgMs assemble into pentamers and hexamers that bind to antigens with high avidity. Pentamers incorporate a small protein called J-chain (JC) that is important for their transcytosis via the poly-immunoglobulin receptor (pIgR). IgM antibodies can efficiently activate complement and interact with different Fc receptors (FcμR, Fcα/μR, pIgR) that trigger distinct effector functions and biodistribution. Even if these features have made the clinical use of IgM attractive over the past decades, there are currently no approved therapeutic IgMs on the market. In this review, we summarize the recent advances in the knowledge of IgM biogenesis and structure and discuss the therapeutic opportunities of IgM over IgG arising from high avidity, target clustering, binding to distinct IgM receptors, complement activation, transcytosis, and protein engineering opportunities. In addition, we summarize possibilities and outstanding challenges in the production of therapeutic IgM, including available technologies for IgM purification. Finally, we review recent preclinical and clinical data showing that IgM outperforms IgG in various in vitro assays but still fails to pass through clinical trials successfully. Challenges remain for IgM development, such as the need for a better understanding of IgM biology to facilitate a smoother transition from the preclinic to successful clinical trials.

Matchmaking at the cell surface using bispecifics to put cells on their best behavior

Intermolecular relationships at the cell surface dictate the behavior and regulatory network of cells. Such interactions often require precise spatial control for optimal response. By binding simultaneously to two different target sites, bispecific binders can bridge molecules of interest. Despite decades of bispecific development, only recently have bispecifics been engineered with programmable, tuneable geometries to replicate natural interaction geometries or achieve new responses from unnatural arrangements. This review highlights emerging methods of protein engineering and modular bioconjugation to control pairing and orientation of binders in bispecific scaffolds. We also describe novel biophysical and phenotypic assays, which reveal how bispecific geometries change cell fate. These approaches are informing design of next-generation precision therapeutics, as well as uncovering fundamental features of signal integration.

Biomembrane structure at the molecular level and its application in precision medicine

Biomembranes are fundamental to our understanding of the cell, the basic building block of all life. They form important barriers between the cytoplasm and the microenvironment of the cell and separate organelles within cells. Despite substantial advances in the study of cell membrane structure models, they are still in the stage of model hypothesis due to the high complexity of the components, structures, and functions of membranes. In this review, we summarized the progresses on membrane structure, properties, and functions at the molecular level using newly developed technologies and discussed some challenges and future directions in biomembrane research from our perspective. Moreover, we demonstrated the dynamic functions of membrane proteins and their role in achieving early detection, precise diagnosis, and the development of personalized treatment strategies at the molecular level. Overall, this review aims to engage researchers in related fields and multidisciplinary readers to understand and explore biomembranes for the accurate and effective development of membrane-targeting therapeutic agents.

Enhancing complement activation by therapeutic anti-tumor antibodies: Mechanisms, strategies, and engineering approaches

The complement system plays an integral role in both innate and adaptive immune responses. Beyond its protective function against infections, complement is also known to influence tumor immunity, where its activation can either promote tumor progression or mediate tumor cell destruction, depending on the context. One such context can be provided by antibodies, with their inherent capacity to activate the classical complement pathway. In recent years, our understanding of the mechanisms governing complement activation by IgG and IgM antibodies has expanded significantly. At the same time, preclinical and clinical studies on antibodies such as rituximab, ofatumumab, and daratumumab have provided evidence for the role of complement in therapeutic success, encouraging strategies to further enhance its activity. In this review we examine the main determinants of antibody-mediated complement activation, highlighting the importance of antibody subclass, affinity, valency, and geometry of antigen engagement. We summarize the evidence for complement involvement in anti-tumor activity and challenges of accurately estimating the extent of its contribution to therapeutic efficacy. Furthermore, we explore several engineering approaches designed to enhance complement activation, including increased Fc oligomerization and C1q affinity, bispecific C1q-recruiting antibodies, IgG subclass chimeras, as well as antibody and paratope combinations. Strategies targeting membrane-bound complement regulatory proteins to overcome tumor-associated complement inhibition are also discussed as a method to boost therapeutic efficacy. Finally, we highlight the potential of complement-dependent cellular cytotoxicity (CDCC) and complement-dependent cellular phagocytosis (CDCP) as effector mechanisms that warrant deeper investigation. By integrating advances in antibody and complement biology with insights from efforts to enhance complement activation in therapeutic antibodies, this review aims to provide a comprehensive framework of antibody design and engineering strategies that optimize complement activity for improved anti-tumor efficacy.

Microenvironment-confined kinetic elucidation and implementation of a DNA nano-phage with a shielded internal computing layer

Multiple receptor analysis-based DNA molecular computation has been developed to mitigate the off-target effect caused by nonspecific expression of cell membrane receptors. However, it is quite difficult to involve nanobodies into molecular computation with programmed recognition order because of the "always-on" response mode and the inconvenient molecular programming. Here we propose a spatial segregation-based molecular computing strategy with a shielded internal computing layer termed DNA nano-phage (DNP) to program nanobody into DNA molecular computation and build a series of kinetic models to elucidate the mechanism of microenvironment-confinement. We explain the contradiction between fast molecular diffusion and effective DNA computation using a "diffusion trap" theory and comprehensively overcome the kinetic bottleneck of DNP by determining the rate-limiting step. We predict and verify that identifying trace amount of target cells in complex cell mixtures is an intrinsic merit of microenvironment-confined DNA computation. Finally, we show that DNP can efficiently work in complex human blood samples by shielding the interference of erythrocytes and enhance phagocytosis of macrophages toward target cells by blocking CD47-SIRPα pathway.

Programmable Circular Multivalent Nanobody-Targeting Chimeras (mNbTACs) for Multireceptor-Mediated Protein Degradation and Targeted Drug Delivery

Multispecific therapeutics hold significant promise in drug delivery, protein degradation, and cell recruitment to address clinical issues of tumor heterogeneity, resistance, and immune evasion. However, their modular engineering remains challenging. We developed a targeted degradation platform, termed multivalent nanobody-targeting chimeras (mNbTACs), by encoding diverse nanobody codons on a circular template using DNA printing technology. The homo- or hetero- mNbTACs specifically recognized membrane targets in a multivalent manner and simultaneously recruited scavenger receptors to favor clathrin-/caveolae-dependent endocytosis and lysosomal degradation of multiple proteins with high efficiency and selectivity. We demonstrated that a bispecific doxorubicin-loaded mNbTAC, named Doxo-mvNbsPPH, passively accumulated at tumor sites, specifically interacted with PD-L1 and HER2 targets, and was rapidly transported into lysosome, inducing potent immunogenic cell death and alleviating immune checkpoint evasion. The synergistic boosting of innate and adaptive immunity promoted the infiltration and proliferation of CD8+ T cells in tumor microenvironment (an 11-fold increase) with high toxicity and low exhaustion, eventually enhancing antitumor efficacy. Our mNbTAC platform provides multispecific therapeutics with variable valences and programmed species, whereas it induces targeted protein degradation through multireceptor-mediated endocytosis and lysosomal degradation without the need for lysosome-targeting receptors, representing a general and modular tool to harness extracellular proteome for disease treatment.

Strategies to boost antibody selectivity in oncology

Antibodies in oncology are being equipped with toxic cargoes and effector functions that can kill cells at very low concentrations. A key challenge is that most targets on cancer cells are also present on at least some healthy cells. Shared targets can result in off-tumor binding and compromise the safety and potential of therapeutic candidates. In this review, we survey strategies that can help direct biologics to cancer sites more selectively. These strategies are becoming increasingly feasible thanks to advances in molecular design and engineering. The objective is to create therapeutics that exploit changes in cancer and leverage the human body infrastructure, enabling therapeutics that discriminate not just self from non-self but diseased from healthy tissue.

Identifying optimal tumor-associated antigen combinations with single-cell genomics to enable multi-targeting therapies

Targeted antibody-based therapy for oncology represents a highly efficacious approach that has demonstrated robust responses against single tumor-associated antigen (TAA) targets. However, tumor heterogeneity presents a major obstacle for targeting most solid tumors due to a lack of single targets that possess the right on-tumor/off-tumor expression profile required for adequate therapeutic index. Multi-targeting antibodies that engage two TAAs simultaneously may address this challenge through Boolean logic-gating function by improving both therapeutic specificity and efficacy. In addition to the complex engineering of multi-targeting antibodies for ideal logic-gate function, selecting optimal TAA combinations ab initio is the critical step to initiate preclinical development but remains largely unexplored with modern data-generation platforms. Here, we propose that single-cell atlases of both primary tumor and normal tissues are uniquely positioned to unveil optimal target combinations for multi-targeting antibody therapeutics. We review the most recent progress in multi-targeting antibody clinical development, as well as the designs of current TAA combinations currently exploited. Ultimately, we describe how multi-targeting antibodies tuned to target pairs nominated through a data-driven process are poised to revolutionize therapeutic safety and efficacy, particularly for difficult-to-treat solid tumors.

Enhancing Fc-mediated effector functions of monoclonal antibodies: The example of HexaBodies

Since the approval of the CD20-targeting monoclonal antibody (mAb) rituximab for the treatment of lymphoma in 1997, mAb therapy has significantly transformed cancer treatment. With over 90 FDA-approved mAbs for the treatment of various hematological and solid cancers, modern cancer treatment relies heavily on these therapies. The overwhelming success of mAbs as cancer therapeutics is attributed to their broad applicability, high safety profile, and precise targeting of cancer-associated surface antigens. Furthermore, mAbs can induce various anti-tumor cytotoxic effector mechanisms including antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement-dependent cytotoxicity (CDC), all of which are mediated via their fragment crystallizable (Fc) domain. Over the past decades, these effector mechanisms have been substantially improved through Fc domain engineering. In this review, we will outline the different approaches to enhance Fc effector functions via Fc engineering of mAbs, with a specific emphasis on the so-called "HexaBody" technology, which is designed to enhance the hexamerization of mAbs on the target cell surface, thereby inducing greater complement activation, CDC, and receptor clustering. The review will summarize the development, preclinical, and clinical testing of several HexaBodies designed for the treatment of B-cell malignancies, as well as the potential use of the HexaBody technology beyond Fc-mediated effector functions.

Stellabody: A novel hexamer-promoting mutation for improved IgG potency

Advances in antibody engineering are being directed at the development of next generation immunotherapeutics with improved potency. Hexamerisation of IgG is a normal physiological aspect of IgG biology and recently described mutations that facilitate this process have a substantial impact upon monoclonal antibody behavior resulting in the elicitation of dramatically enhanced complement-dependent cytotoxicity, Fc receptor function, and enhanced antigen binding effects, such as targeted receptor agonism or microbe neutralization. Whereas the discovery of IgG hexamerisation enhancing mutations has largely focused on residues with exposure at the surface of the Fc-Fc and CH2-CH3 interfaces, our unique approach is the engineering of the mostly buried residue H429 in the CH3 domain. Selective substitution at position 429 forms the basis of Stellabody technology, where the choice of amino acid results in distinct hexamerisation outcomes. H429F results in monomeric IgG that hexamerises after target binding, so called "on-target" hexamerisation, while the H429Y mutant forms pH-sensitive hexamers in-solution prior to antigen binding. Moreover, Stellabody technologies are broadly applicable across the family of antibody-based biologic therapeutics, including conventional mAbs, bispecific mAbs, and Ig-like biologics such as Fc-fusions, with applications in diverse diseases.

A DNA Molecular Logic Circuit for Precise Tumor Identification

Tumor-associated antigens (TAAs) are not exclusively expressed in cancer cells, inevitably causing the "on target, off tumor" effect of molecular recognition tools. To achieve precise recognition of cancer cells, by using protein tyrosine kinase 7 (PTK7) as a model TAA, a DNA molecular logic circuit Aisgc8 was rationally developed by arranging H+-binding i-motif, ATP-binding aptamer, and PTK7-targeting aptamer Sgc8c in a DNA sequence. Aisgc8 output the conformation of Sgc8c to recognize PTK7 on cells in a simulated tumor microenvironment characterized by weak acidity and abundant ATP, but not in a simulated physiological environment. Through in vitro and in vivo results, Aisgc8 demonstrated its ability to precisely recognize cancer cells and, as a result, displayed excellent performance in tumor imaging. Thus, our studies produced a simple and efficient strategy to construct DNA logic circuits, opening new possibilities to develop convenient and intelligent precision diagnostics by using DNA logic circuits.

Therapeutic potential of cis-targeting bispecific antibodies

The growing clinical success of bispecific antibodies (bsAbs) has led to rapid interest in leveraging dual targeting in order to generate novel modes of therapeutic action beyond mono-targeting approaches. While bsAbs that bind targets on two different cells (trans-targeting) are showing promise in the clinic, the co-targeting of two proteins on the same cell surface through cis-targeting bsAbs (cis-bsAbs) is an emerging strategy to elicit new functionalities. This includes the ability to induce proximity, enhance binding to a target, increase target/cell selectivity, and/or co-modulate function on the cell surface with the goal of altering, reversing, or eradicating abnormal cellular activity that contributes to disease. In this review, we focus on the impact of cis-bsAbs in the clinic, their emerging applications, and untangle the intricacies of improving bsAb discovery and development.

Selection and characterization of a peptide-based complement modulator targeting C1 of the innate immune system

The human complement pathway plays a pivotal role in immune defence, homeostasis, and autoimmunity regulation, and complement-based therapeutics have emerged as promising interventions, with both antagonistic and agonistic approaches being explored. The classical pathway of complement is initiated when the C1 complex binds to hexameric antibody platforms. Recent structural data revealed that C1 binds to small, homogeneous interfaces at the periphery of the antibody platforms. Here, we have developed a novel strategy for complement activation using macrocyclic peptides designed to mimic the interface between antibodies and the C1 complex. In vitro selection utilizing the RaPID system identified a cyclic peptide (cL3) that binds to the C1 complex via the globular head domains of C1q. Notably, when immobilized on surfaces, cL3 effectively recruits C1 from human serum, activates C1s proteases, and induces lysis of cell-mimetic lipid membranes. This represents the first instance of a peptide capable of activating complement by binding C1 when immobilized. Further characterization and synthesis of deletion mutants revealed a critical cycle size of cL3 essential for C1 binding and efficient complement activation. Importantly, cL3 also demonstrated the ability to inhibit complement-mediated lysis without affecting C1 binding, highlighting its potential as a therapeutic modality to prevent complement-dependent cytotoxicity whilst promoting cellular phagocytosis and cell clearance. In summary, this study introduces the concept of "Peptactins" - peptide-based activators of complement - and underscores the potential of macrocyclic peptides for complement modulation, offering potential advantages over traditional biologicals in terms of size, production, and administration.

Engineering Agonistic Bispecifics to Investigate the Influence of Distance on Surface-Mediated Complement Activation

The development of agonists capable of activating the human complement system by binding to the C1 complex presents a novel approach for targeted cell killing. Bispecific nanobodies and Abs can successfully use C1 for this purpose; however, efficacy varies significantly between epitopes, Ab type, and bispecific design. To address this variability, we investigated monomeric agonists of C1 in the form of bispecific nanobodies, which lack Fc domains that lead to oligomerization in Abs. These therefore offer an ideal opportunity to explore the geometric parameters crucial for C1 activation. In this study, we explored the impact of linker length as a metric for Ag and epitope location. DNA nanotechnology and protein engineering allowed us to design linkers with controlled lengths and flexibilities, revealing a critical range of end-to-end distances for optimal complement activation. We discovered that differences in complement activation were not caused by differential C1 activation or subsequent cleavage of C4, but instead impacted C4b deposition and downstream membrane lysis. Considering the importance of Ab class and subclass, this study provides insights into the structural requirements of C1 binding and activation, highlighting linker and hinge engineering as a potential strategy to enhance potency over specific cellular targets. Additionally, using DNA nanotechnology to modify geometric parameters demonstrated the potential for synthetic biology in complement activation. Overall, this research offers valuable insights into the design and optimization of agonists for targeted cell killing through complement activation.

Cancer therapy with antibodies

The greatest challenge in cancer therapy is to eradicate cancer cells with minimal damage to normal cells. Targeted therapy has been developed to meet that challenge, showing a substantially increased therapeutic index compared with conventional cancer therapies. Antibodies are important members of the family of targeted therapeutic agents because of their extraordinarily high specificity to the target antigens. Therapeutic antibodies use a range of mechanisms that directly or indirectly kill the cancer cells. Early antibodies were developed to directly antagonize targets on cancer cells. This was followed by advancements in linker technologies that allowed the production of antibody-drug conjugates (ADCs) that guide cytotoxic payloads to the cancer cells. Improvement in our understanding of the biology of T cells led to the production of immune checkpoint-inhibiting antibodies that indirectly kill the cancer cells through activation of the T cells. Even more recently, bispecific antibodies were synthetically designed to redirect the T cells of a patient to kill the cancer cells. In this Review, we summarize the different approaches used by therapeutic antibodies to target cancer cells. We discuss their mechanisms of action, the structural basis for target specificity, clinical applications and the ongoing research to improve efficacy and reduce toxicity.

The present and future of bispecific antibodies for cancer therapy

Bispecific antibodies (bsAbs) enable novel mechanisms of action and/or therapeutic applications that cannot be achieved using conventional IgG-based antibodies. Consequently, development of these molecules has garnered substantial interest in the past decade and, as of the end of 2023, 14 bsAbs have been approved: 11 for the treatment of cancer and 3 for non-oncology indications. bsAbs are available in different formats, address different targets and mediate anticancer function via different molecular mechanisms. Here, we provide an overview of recent developments in the field of bsAbs for cancer therapy. We focus on bsAbs that are approved or in clinical development, including bsAb-mediated dual modulators of signalling pathways, tumour-targeted receptor agonists, bsAb-drug conjugates, bispecific T cell, natural killer cell and innate immune cell engagers, and bispecific checkpoint inhibitors and co-stimulators. Finally, we provide an outlook into next-generation bsAbs in earlier stages of development, including trispecifics, bsAb prodrugs, bsAbs that induce degradation of tumour targets and bsAbs acting as cytokine mimetics.

Tumor Microenvironment Remodeling-Mediated Sequential Drug Delivery Potentiates Treatment Efficacy

Toll-like receptor 7/8 agonists, such as imidazoquinolines (IMDQs), are promising for the de novo priming of antitumor immunity. However, their systemic administration is severely limited due to the off-target toxicity. Here, this work describes a sequential drug delivery strategy. The formulation is composed of two sequential modules: a tumor microenvironment remodeling nanocarrier (poly(l-glutamic acid)-graft-methoxy poly(ethylene glycol)/combretastatin A4, termed CA4-NPs) and an immunotherapy nanocarrier (apcitide peptide-decorated poly(l-glutamic acid)-graft-IMDQ-N3 conjugate, termed apcitide-PLG-IMDQ-N3 ). CA4-NPs, as a vascular disrupting agent, are utilized to remodel the tumor microenvironment for enhancing tumor coagulation and hypoxia. Subsequently, the apcitide-PLG-IMDQ-N3 could identify and target tumor coagulation through the binding of surface apcitide peptide to the GPIIb-IIIa on activated platelets. Afterward, IMDQ is activated selectively through the conversion of "-N3 " to "-NH2 " in the presence of hypoxia. The biodistribution results confirm their high tumor uptake of activated IMDQ (22.66%ID/g). By augmenting the priming and immunologic memory of tumor-specific CD8+ T cells, 4T1 and CT26 tumors with a size of ≈500 mm3 are eradicated without recurrence in mouse models.

Flow cytometry: Aspects and application in plant and biological science

Flow cytometry is a potent method that enables the quick and concurrent investigation of several characteristics of single cells in solution. Photodiodes or photomultiplier tubes are employed to detect the dispersed and fluorescent light signals that are produced by the laser beam as it passes through the cells. Photodetectors transform the light signals produced by the laser into electrical impulses. A computer then analyses these electrical impulses to identify and measure the various cell populations depending on their fluorescence or light scattering characteristics. Based on their fluorescence or light scattering properties, cell populations can be examined and/or isolated. This review covers the basic principle, components, working and specific biological applications of flow cytometry, including studies on plant, cell and molecular biology and methods employed for data processing and interpretation as well as the potential future relevance of this methodology in light of retrospective analysis and recent advancements in flow cytometry.

Impact of structural modifications of IgG antibodies on effector functions

Immunoglobulin G (IgG) antibodies are a critical component of the adaptive immune system, binding to and neutralizing pathogens and other foreign substances. Recent advances in molecular antibody biology and structural protein engineering enabled the modification of IgG antibodies to enhance their therapeutic potential. This review summarizes recent progress in both natural and engineered structural modifications of IgG antibodies, including allotypic variation, glycosylation, Fc engineering, and Fc gamma receptor binding optimization. We discuss the functional consequences of these modifications to highlight their potential for therapeutical applications.

Cell surface sculpting using logic-gated protein actuators

Cell differentiation and tissue specialization lead to unique cellular surface landscapes and exacerbated or loss of expression patterns can result in further heterogenicity distinctive of pathological phenotypes1-3. Immunotherapies and emerging protein therapeutics seek to exploit such differences by engaging cell populations selectively based on their surface markers. Since a single surface antigen rarely defines a specific cell type4,5, the development of programmable molecular systems that integrate multiple cell surface features to convert on-target inputs to user-defined outputs is highly desirable. Here, we describe an autonomous decision-making protein device driven by proximity-gated protein trans-splicing that allows local generation of an active protein from two otherwise inactive fragments. We show that this protein actuator platform can perform various Boolean logic operations on cell surfaces, allowing highly selective recruitment of enzymatic and cytotoxic activities to specific cells within mixed populations. Due to its intrinsic modularity and tunability, this technology is expected to be compatible with different types of inputs, targeting modalities and functional outputs, and as such will have broad application in the synthetic biology and biotechnology areas.

Improving the tumor selectivity of T cell engagers by logic-gated dual tumor-targeting

Targeting single tumor antigens makes it difficult to provide sufficient tumor selectivity for T cell engagers (TCEs), leading to undesirable toxicity and even treatment failure, which is particularly serious in solid tumors. Here, we designed novel trispecific TCEs (TriTCEs) to improve the tumor selectivity of TCEs by logic-gated dual tumor-targeting. TriTCE can effectively redirect and activate T cells to kill tumor cells (~18 pM EC₅₀) by inducing the aggregation of dual tumor antigens, which was ~70- or 750- fold more effective than the single tumor-targeted isotype controls, respectively. Further in vivo experiments indicated that TriTCE has the ability to accumulate in tumor tissue and can induce circulating T cells to infiltrate into tumor sites. Hence, TriTCE showed a stronger tumor growth inhibition ability and significantly prolonged the survival time of the mice. Finally, we revealed that this concept of logic-gated dual tumor-targeted TriTCE can be applied to target different tumor antigens. Cumulatively, we reported novel dual tumor-targeted TriTCEs that can mediate a robust T cell response by simultaneous recognition of dual tumor antigens at the same cell surface. TriTCEs allow better selective T cell activity on tumor cells, resulting in safer TCE treatment.

A new dawn for monoclonal antibodies against antimicrobial resistant bacteria

Antimicrobial resistance (AMR) is a quickly advancing threat for human health worldwide and almost 5 million deaths are already attributable to this phenomenon every year. Since antibiotics are failing to treat AMR-bacteria, new tools are needed, and human monoclonal antibodies (mAbs) can fill this role. In almost 50 years since the introduction of the first technology that led to mAb discovery, enormous leaps forward have been made to identify and develop extremely potent human mAbs. While their usefulness has been extensively proved against viral pathogens, human mAbs have yet to find their space in treating and preventing infections from AMR-bacteria and fully conquer the field of infectious diseases. The novel and most innovative technologies herein reviewed can support this goal and add powerful tools in the arsenal of weapons against AMR.

A Tool, an App and a Field: Fluorescent PET Sensors, Blood Electrolyte Analysis and Molecular Logic as Products of Supramolecular Photoscience from Northern Ireland and Sri Lanka

The general tool of fluorescent PET (photoinduced electron transfer) sensors/switches - a molecular design principle with engineering features - is outlined, with the aid of frontier orbital energy diagrams. Fluorophores such as anthracene, 1,3-diaryl-Δ² -pyrazolines and 4-amino-1,8-naphthalimides are employed within this system, alongside receptors such as amines, carboxylates, crown ethers and amino acids. This tool appealed to a multinational corporation for building a medical analyzer for electrolytes such as Na⁺ , K⁺ , Ca²⁺ and gases like CO₂ , which became a commercially successful application. Finally, the tool was a springboard for chemistry to cross into computer science. The field of molecular logic can elucidate how molecules inside us handle information. Molecular examples of the simplest logic gates such as YES, NOT, OR, AND are described. A case of a human-level computation - visual edge detection - is also included.