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Background: Inflammation involves a dynamic network that is highly regulated by signals that initiate the inflammation process as well as signals that downregulate it. However, an imbalance between the two leads to tissue damage. Throughout the world, inflammatory disease becomes common in the aging society. The drugs which are used clinically have serious side effects. Natural products or compounds derived from natural products show diversity in structure and play an important role in drug discovery and development. Objective: Oreganum Vulgare is used in traditional medicine for various ailments including respiratory and rheumatic disorders, severe cold, suppression of tumors. The current study aims to evaluate the anti-inflammatory potential by evaluating various in vitro parameters. Methods: Inflammation-induced in macrophages via LPS is the most accepted model for evaluating the antiinflammatory activity of various plant extracts and lead compounds. Results: The extracts (OVEE, OVEAF) as well as the isolated compound(OVRA)of Oreganum Vulgare inhibit the pro-inflammatory cytokines (IL-6 and TNF-α) and NO without affecting cell viability. Conclusion: Our study established that the leaf extracts of Oreganum vulgare L. exhibit anti-inflammatory activity and thus confirm its importance in traditional medicine.

Objective. Systemic lupus erythematosus (SLE) is a common chronic autoimmune inflammatory disease. According to recent studies, signaling through Toll-like receptor (TLR) protein, which promotes the production of inflammatory cytokines, leads to the development of SLE. TLR-inhibitory peptide 1 (TIP1) has been newly identified for the treatment of autoimmune diseases. Methods. The effect of TIP1 was analyzed in an SLE mouse model (MRL/lpr). The mice in the control treatment group (n=5) were administered an intravenous injection of phosphate-buffered saline twice weekly, whereas the mice in the TIP1 treatment group (n=6) were administered an intravenous injection of TIP1 (1 nmol/g) twice weekly. MRL/mpj mice (n=5) were selected as normal controls. The mice were injected for 4 weeks between 14 and 18 weeks of age, followed by assays of their spleen, kidneys, lymph nodes, serum, and urine. Results. The antinuclear antibody and inflammatory cytokine (interferon-α) in the serum as well as levels of albumin in the urine of the mice in the TIP1 treatment group had decreased when compared to those of mice in the control treatment group. Kidney inflammation in mice in the TIP1 treatment group was alleviated. The mRNA expression levels of TLR7- or TLR9-related downstream signaling molecules also decreased in all organs of the mice in the TIP1 treatment group. Conclusion. Intravenous treatment with TIP1 reduces symptoms and markers of inflammation in MRL/lpr mice. Hence, TIP1 is a promising medication for the treatment of SLE. (J Rheum Dis 2021;28:133-142)

Graphical abstract, Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), is a novel beta coronavirus. SARS-CoV-2 uses spike glycoprotein to interact with host angiotensin-converting enzyme 2 (ACE2) and ensure cell recognition. High infectivity of SARS-CoV-2 raises questions on spike-ACE2 binding affinity and its neutralization by anti-SARS-CoV monoclonal antibodies (mAbs). Here, we observed Val-to-Lys417 mutation in the receptor-binding domains (RBD) of SARS-CoV-2, which established a Lys-Asp electrostatic interaction enhancing its ACE2-binding. Pro-to-Ala475 substitution and Gly482 insertion in the AGSTPCNGV-loop of RBD possibly hinders neutralization of SARS-CoV-2 by anti-SARS-CoV mAbs. In addition, we identified unique and structurally conserved conformational-epitopes on RBDs, which can be potential therapeutic targets. Collectively, we provide new insights into the mechanisms underlying the high infectivity of SARS-CoV-2 and development of effective neutralizing agents.

Toll-like receptors (TLRs) play a major role in the innate immune system. Several studies have shown the regulatory effects of TLR-mediated pathways on immune and inflammatory diseases. Dysregulated functions of TLRs within the endosomal compartment, including TLR7/9 trafficking, may cause systemic lupus erythematosus (SLE). TLR signaling pathways are fine-tuned by Toll/interleukin-1 receptor (TIR) domain-containing adapters, leading to interferon (IFN)-α production. This study describes a TLR inhibitor peptide 1 (TIP1) that primarily suppresses the downstream signaling mediated by TIR domain-containing adapters in an animal model of lupus and patients with SLE. The expression of most downstream proteins of the TLR7/9/myeloid differentiation factor 88 (MyD88)/IFN regulatory factor 7 signaling was downregulated in major tissues such as the kidney, spleen, and lymph nodes of treated mice. Furthermore, the pathological analysis of the kidney tissue confirmed that TIP1 could improve inflammation in MRL/lpr mice. TIP1 treatment downregulated many downstream proteins associated with TLR signaling, such as MyD88, interleukin-1 receptor-associated kinase, tumor necrosis factor receptor-associated factor 6, and IFN-α, in the peripheral blood mononuclear cells of patients with SLE. In conclusion, our data suggest that TIP1 can serve as a potential candidate for the treatment of SLE.

Toll-like receptors (TLRs) are the pattern recognition receptors, which are activated by foreign and host molecules in order to initiate the immune response. They play a crucial role in the regulation of innate immunity, and several studies have shown their importance in bacterial, viral, and fungal infections, autoimmune diseases, and cancers. The consensus view from an immunological perspective is that TLR agonists can serve either as a possible therapeutic agent or as a vaccine adjuvant toward cancers or infectious diseases and that TLR inhibitors may be a promising approach to the treatment of autoimmune diseases, some cancers, bacterial, and viral infections. These notions are based on the fact that TLR agonists stimulate the secretion of proinflammatory cytokines and in general, the development of proinflammatory responses. Some of the TLR-based inhibitory agents have shown to be efficacious in preclinical models and have now entered clinical trials. Therefore, TLRs seem to hold the potential to serve as a perfect target in the era of immunotherapies. We offer a perspective on TLR-based therapeutics that sheds light on their usefulness and on combination therapies. We also highlight various therapeutics that are in the discovery phase or in clinical trials.

A mounting evidence exists for the despicable role of the aberrant immune response in the pathogenesis of rheumatoid arthritis (RA), where toll-like receptor 4 (TLR4) can activate synovial fibroblasts that lead to the chronic inflammation and joint destruction, thus making TLR4 a potent drug target in RA. We report that novel TLR4-antagonizing peptide, PIP2, inhibits the induction of inflammatory biomarkers in vitro as well as in vivo. Systemically, PIP2 inhibits the lipopolysaccharide (LPS)-elicited TNF-α, IL-6, and IL-12p40 in a mouse model. The rationally designed cyclic derivative, cPIP2, is capable of inhibiting LPS-induced proinflammatory cytokines at significantly lower concentration as compared to PIP2 (PIP2 IC50 = 20 μM, cPIP2 IC50 = 5 μM). Finally, cPIP2 was able to relieve the inflammatory symptoms and synovial tissue destruction in the RA rat model. Cumulatively, these data suggest that PIP2 and cPIP2 hold strong promise for the development of peptide-based immunotherapeutics that could be of ...

Toll-like receptors (TLRs) recognize pathogen/damage-associated molecular patterns and initiate inflammatory signaling cascades. Occasionally, overexpression of TLRs leads to the onset of numerous inflammatory diseases, necessitating the development of selective inhibitors to allow a protective yet balanced immune response. Here, we demonstrate that a novel peptide (TIP1) derived from Toll/interleukin-1 receptor (TIR) domain-containing adapter protein inhibited multiple TLR signaling pathways (MyD88-dependent and MyD88-independent) in murine and human cell lines. TIP1 also inhibited NLRP3-mediated IL-1β secretion, as we validated at both the protein and mRNA levels. Biophysical experiments confirmed that TIP1 specifically binds to the BB loop of the TLR4-TIR domain. Animal studies revealed that TIP1 inhibited the secretion of lipopolysaccharide (LPS)-induced proinflammatory cytokines in collagen-induced arthritis (CIA) and kaolin/carrageenan-induced arthritis (K/C) rodent models. TIP1 also rescued animals from sepsis and from LPS-induced kidney/liver damage. Importantly, TIP1 ameliorated the symptoms of rheumatoid arthritis in CIA and K/C rodent models, suggesting that TIP1 has therapeutic potential for the treatment of TLR-mediated autoimmune/inflammatory diseases., Inflammation: A decoy peptide treats arthritis and sepsis in mice A newly discovered peptide drug that disrupts signaling through a critical immune pathway could offer a new treatment for inflammatory diseases. Sangdun Choi from Ajou University in Suwon, South Korea, and colleagues designed the drug to look similar to—and thus act as kind of decoy for—a protein that regulates signaling through Toll-like receptors (TLRs), proteins found on immune cells that initiate responses to pathogens and also play a role in autoimmunity. In mouse and human cells, the drug inhibited multiple TLR signaling pathways, including a pathway that normally activates a multiprotein complex implicated in a variety of inflammatory diseases. In mouse models of rheumatoid arthritis and sepsis, the drug limited the release of proinflammatory molecules in the blood and reduced disease symptoms.

RNA viruses, including the coronavirus, develop a unique strategy to evade the host immune response by interrupting the normal function of cytosolic retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs). RLRs rapidly detect atypical nucleic acids, thereby triggering the antiviral innate immune signaling cascade and subsequently activates the interferons transcription and induction of other proinflammatory cytokines and chemokines. Nonetheless, these receptors are manipulated by viral proteins to subvert the host immune system and sustain the infectivity and replication potential of the virus. RIG-I senses the single-stranded, double-stranded, and short double-stranded RNAs and recognizes the key signature, a 5'-triphosphate moiety, at the blunt end of the viral RNA. Meanwhile, the melanoma differentiation-associated gene 5 (MDA5) is triggered by longer double stranded RNAs, messenger RNAs lacking 2'-O-methylation in their 5'-cap, and RNA aggregates. Therefore, structural insights into the nucleic-acid-sensing and downstream signaling mechanisms of these receptors hold great promise for developing effective antiviral therapeutic interventions. This review highlights the critical roles played by RLRs in viral infections as well as their ligand recognition mechanisms. In addition, we highlight the crosstalk between the toll-like receptors and RLRs and provide a comprehensive overview of RLR-associated diseases as well as the therapeutic potential of RLRs for the development of antiviral-drugs. Moreover, we believe that these RLR-based antivirals will serve as a step toward countering the recent coronavirus disease 2019 pandemic.

Toll-like receptor (TLR) signaling plays a critical role in the induction and progression of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematous, experimental autoimmune encephalitis, type 1 diabetes mellitus and neurodegenerative diseases. Deciphering antigen recognition by antibodies provides insights and defines the mechanism of action into the progression of immune responses. Multiple strategies, including phage display and hybridoma technologies, have been used to enhance the affinity of antibodies for their respective epitopes. Here, we investigate the TLR4 antibody-binding epitope by computational-driven approach. We demonstrate that three important residues, i.e., Y328, N329, and K349 of TLR4 antibody binding epitope identified upon in silico mutagenesis, affect not only the interaction and binding affinity of antibody but also influence the structural integrity of TLR4. Furthermore, we predict a novel epitope at the TLR4-MD2 interface which can be targeted and explored for therapeutic antibodies and small molecules. This technique provides an in-depth insight into antibody–antigen interactions at the resolution and will be beneficial for the development of new monoclonal antibodies. Computational techniques, if coupled with experimental methods, will shorten the duration of rational design and development of antibody therapeutics.

Acidovorax avenae is a flagellated, pathogenic bacterium to various plant crops that has also been found in human patients with haematological malignancy, fever, and sepsis, however, the exact mechanism for infection in humans is not known. We hypothesized that the human innate immune system could be responsive to the purified flagellin isolated from A. avenae, named FLA-AA. We observed the secretion of inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, and IL-8 by treating FLA-AA to human dermal fibroblasts, as well as macrophages. This response was exclusively through TLR5, which was confirmed by using TLR5-overexpression cell line, 293/hTLR5, as well as TLR5-specific inhibitor, TH1020. We also observed the secretion of inflammatory cytokine, IL-1β, by the activation of NLRC4 with FLA-AA. Overall, our results provide a molecular basis for the inflammatory response caused by FLA-AA in cell-based assays.

Thioredoxin-interacting protein (TXNIP), widely known as thioredoxin-binding protein 2 (TBP2), is a major binding mediator in the thioredoxin (TXN) antioxidant system, which involves a reduction-oxidation (redox) signaling complex and is pivotal for the pathophysiology of some diseases. TXNIP increases reactive oxygen species production and oxidative stress and thereby contributes to apoptosis. Recent studies indicate an evolving role of TXNIP in the pathogenesis of complex diseases such as metabolic disorders, neurological disorders, and inflammatory illnesses. In addition, TXNIP has gained significant attention due to its wide range of functions in energy metabolism, insulin sensitivity, improved insulin secretion, and also in the regulation of glucose and tumor suppressor activities in various cancers. This review aims to highlight the roles of TXNIP in the field of diabetology, neurodegenerative diseases, and inflammation. TXNIP is found to be a promising novel therapeutic target in the current review, not only in the aforementioned diseases but also in prolonged microvascular and macrovascular diseases. Therefore, TXNIP inhibitors hold promise for preventing the growing incidence of complications in relevant diseases.

Renal ischemia-reperfusion injury (IRI) is involved in the majority of clinical conditions that manifest as renal function deterioration, however, specific treatment for this type of injury is still far from clinical use. Since Toll-like receptor (TLR)-mediated signaling is a key mediator of IRI, we examined the effect of a multiple-TLR-blocking peptide named TLR-inhibitory peptide 1 (TIP1), which exerts the strongest action on TLR4, on renal IRI. We subjected C57BL/6 mice to 23 min of renal pedicle clamping preceded by intraperitoneal injection with a vehicle or TIP1. Sham control mice underwent flank incision only. Mouse kidneys were harvested after 24 h of reperfusion for histology, western blot, RT-PCR, and flow cytometry analysis. Pretreatment with TIP1 lowered the magnitude of elevated plasma creatinine levels and attenuated tubular injury. TIP1 treatment also reduced mRNA expression of inflammatory cytokines and decreased apoptotic cells and oxidative stress in post-ischemic kidneys. In kidneys pretreated with TIP1, the infiltration of macrophages and T helper 17 cells was less abundant than those in the IRI only group. These results suggest that TIP1 has a potential beneficial effect in attenuating the degree of kidney damage induced by IRI.

Direct inhibition of tumor necrosis factor-alpha (TNF-&alpha, ) action is considered a promising way to prevent or treat TNF-&alpha, associated diseases. The trimeric form of TNF-&alpha, binds to its receptor (TNFR) and activates the downstream signaling pathway. The interaction of TNF-&alpha, with molecular-grade dimethyl sulfoxide (DMSO) in an equal volumetric ratio renders TNF-&alpha, inert, in this state, TNF-&alpha, fails to activate TNFR. Here, we aimed to examine the inhibition of TNF-&alpha, function by various concentrations of DMSO. Its higher concentration led to stronger attenuation of TNF-&alpha, induced cytokine secretion by fibroblasts, and of their death. We found that this inhibition was mediated by a perturbation in the formation of the functional TNF-&alpha, trimer. Molecular dynamics simulations revealed a transient interaction between DMSO molecules and the central hydrophobic cavity of the TNF-&alpha, homodimer, indicating that a brief interaction of DMSO with the TNF-&alpha, homodimer may disrupt the formation of the functional homotrimer. We also found that the sensitizing effect of actinomycin D on TNF-&alpha, induced cell death depends upon the timing of these treatments and on the cell type. This study will help to select an appropriate concentration of DMSO as a working solvent for the screening of water-insoluble TNF-&alpha, inhibitors.

The immune system plays a crucial role in the body’s defense system against various pathogens, such as bacteria, viruses, and parasites, as well as recognizes non-self- and self-molecules. The innate immune system is composed of special receptors known as pattern recognition receptors, which play a crucial role in the identification of pathogen-associated molecular patterns from diverse microorganisms. Any disequilibrium in the activation of a particular pattern recognition receptor leads to various inflammatory, autoimmune, or immunodeficiency diseases. Aptamers are short single-stranded deoxyribonucleic acid or ribonucleic acid molecules, also termed “chemical antibodies,” which have tremendous specificity and affinity for their target molecules. Their features, such as stability, low immunogenicity, ease of manufacturing, and facile screening against a target, make them preferable as therapeutics. Immune-system–targeting aptamers have a great potential as a targeted therapeutic strategy against immune diseases. This review summarizes components of the innate immune system, aptamer production, pharmacokinetic characteristics of aptamers, and aptamers related to innate-immune-system diseases.

Toll-like receptors (TLRs) play a fundamental role in the inflammatory response against invading pathogens. However, the dysregulation of TLR-signaling pathways is implicated in several autoimmune/inflammatory diseases. Here, we show that a novel small molecule TLR-inhibitor (TAC5) and its derivatives TAC5-a, TAC5-c, TAC5-d, and TAC5-e predominantly antagonized poly(I:C) (TLR3)-, imiquimod (TLR7)-, TL8-506 (TLR8)-, and CpG-oligodeoxynucleotide (TLR9)-induced signaling pathways. TAC5 and TAC5-a significantly hindered the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-&kappa, B), reduced the phosphorylation of mitogen-activated protein kinases, and inhibited the secretion of tumor necrosis factor-&alpha, (TNF-&alpha, ) and interleukin-6. Besides, TAC5-a prevented the progression of psoriasis and systemic lupus erythematosus (SLE) in mice. Interestingly, TAC5 and TAC5-a did not affect Pam3CSK4 (TLR1/2)-, FSL-1 (TLR2/6)-, or lipopolysaccharide (TLR4)-induced TNF-&alpha, secretion, indicating their specificity towards endosomal TLRs (TLR3/7/8/9). Collectively, our data suggest that the TAC5 series of compounds are potential candidates for treating autoimmune diseases such as psoriasis or SLE.

The integration of computational techniques into drug development has led to a substantial increase in the knowledge of structural, chemical, and biological data. These techniques are useful for handling the big data generated by empirical and clinical studies. Over the last few years, computer-aided drug discovery methods such as virtual screening, pharmacophore modeling, quantitative structure-activity relationship analysis, and molecular docking have been employed by pharmaceutical companies and academic researchers for the development of pharmacologically active drugs. Toll-like receptors (TLRs) play a vital role in various inflammatory, autoimmune, and neurodegenerative disorders such as sepsis, rheumatoid arthritis, inflammatory bowel disease, Alzheimer’s disease, multiple sclerosis, cancer, and systemic lupus erythematosus. TLRs, particularly TLR4, have been identified as potential drug targets for the treatment of these diseases, and several relevant compounds are under preclinical and clinical evaluation. This review covers the reported computational studies and techniques that have provided insights into TLR4-targeting therapeutics. Furthermore, this article provides an overview of the computational methods that can benefit a broad audience in this field and help with the development of novel drugs for TLR-related disorders.

Toll-like receptors (TLRs) represent a family of pattern recognition receptors that recognize certain pathogen-associated molecular patterns and damage-associated molecular patterns. TLRs are highly interesting to researchers including immunologists because of the involvement in various diseases including cancers, allergies, autoimmunity, infections, and inflammation. After ligand engagement, TLRs trigger multiple signaling pathways involving nuclear factor-κB (NF-κB), interferon-regulatory factors (IRFs), and mitogen-activated protein kinases (MAPKs) for the production of various cytokines that play an important role in diseases like cancer. TLR activation in immune as well as cancer cells may prevent the formation and growth of a tumor. Nonetheless, under certain conditions, either hyperactivation or hypoactivation of TLRs supports the survival and metastasis of a tumor. Therefore, the design of TLR-targeting agonists as well as antagonists is a promising immunotherapeutic approach to cancer. In this review, we mainly describe TLRs, their involvement in cancer, and their promising properties for anticancer drug discovery.

Chemotherapy has been linked to a variety of severe side effects, and the bioavailability of current chemotherapeutic agents is generally low, which decreases their effectiveness. Therefore, there is an ongoing effort to develop drug delivery systems to increase the bioavailability of these agents and minimize their side effects. Among these, intratumoral injections using in situ-forming hydrogels can improve drugs’ bioavailability and minimize drugs’ accumulation in non-target organs or tissues. This review describes different types of injectable in situ-forming hydrogels and their intratumoral injection for cancer treatment, after which we discuss the antitumor effects of intratumoral injection of drug-loaded hydrogels. This review concludes with perspectives on the future applicability of, and challenges for, the adoption of this drug delivery technology.

Surface modification of micro- and nanotopography was employed to alter the surface properties of scaffolds for controlling cell attachment, proliferation, and differentiation. This study reports a method for generating multinucleated colonies as evidenced by spherical colony formation through nanotopography-induced expression of reprogramming factors in human dermal fibroblasts. Colony formation was achieved by subjecting the cells to specific environments such as culturing with single-walled carbon nanotubes and poly-l-lysine (PLL-SWCNTs). We obtained encouraging results showing that PLL-SWCNT treatment transformed fibroblast cells, and the transformed cells expressed the pluripotency-associated factors OCT4, NANOG, and SOX2 in addition to TRA-1-60 and SSEA-4, which are characteristic stem cell markers. Downregulation of lamin A/C, HDAC1, HDAC6, Bcl2, cytochrome c, p-FAK, p-ERK, and p-JNK and upregulation of H3K4me3 and p-p38 were confirmed in the generated colonies, indicating reprogramming of cells. This protocol increases the possibility of successfully reprogramming somatic cells into induced pluripotent stem cells (iPSCs), thereby overcoming the difficulties in iPSC generation such as genetic mutations, carcinogenesis, and undetermined risk factors.

Toll-like receptors (TLRs) are transmembrane components that sense danger signals, like damage- and pathogen-associated molecular pattern molecules, as receptors, and maintain homeostasis in tissues. They are mainly involved in immune system activation through a variety of mediators, which either carry out (1) elimination of pathogenic threats and redressing homeostatic imbalances or (2) contribution to the initiation and worsening of pathological conditions, including cancers. Under physiological conditions, TLRs coordinate the innate and adaptive immunity, and inhibit autoimmune disorders. In pathological conditions, such as cancer, they can present both tumor and receptor-specific roles. Although the roles of individual TLRs in various cancers have been described, the effects of targeting TLRs to treat cancer and prevent metastasis are still controversial. A growing body of literature has suggested contribution of both activators and inhibitors of TLR signaling pathway for cancer treatment, dependent on several context-specific factors. In short, TLRs can play dual roles with contradictory outcomes in neoplastic conditions. This hampers the development of TLR-based therapeutic interventions. A better understanding of the interwoven TLR pathways in cancerous microenvironment is necessary to design TLR-based therapies. In this review, we consider the molecular mechanisms of TLRs signaling and their involvement in tumor progression. Therapeutic modalities targeting TLRs for cancer treatment are discussed as well.

Negative regulation of Toll-like receptor-4 (TLR4) is anticipated to control the pathogen-induced exaggerated immune response. However, effective TLR4 antagonists with scarce off-target effects are yet to be developed. To fill this void, we sought to design small peptide-inhibitors of the TLR4/MD2−LPS interaction. Here we report novel TLR4-antagonistic peptides (TAP), identified through phage display, endowed with the LPS-induced proinflammation inhibition, and confirmed in mice. TAPs-attributed TLR4-antagonism were initially evaluated through NF-κB inhibition in HEK-blue hTLR4 and RAW264.7 cells, and further reinforced by the downregulation of MAPKs (mitogen-activated protein kinases), NF-κB, interleukin 6, and suppression of the oxidative-stress products and iNOS in macrophages and human peripheral blood mononuclear cells (hPBMCs). Among these, TAP2 specifically halted the TLR4, but not other TLRs signaling, which was further confirmed by the biophysical kinetic assay. Finally, TAP2 diminished LPS-elicited systemic cytokine response in vivo , suggesting that TAPs, specifically TAP2, have the potential to treat TLR4-mediated immune ailments.

In the present study, poly(amidoamine)/5-fluorouracil (PAMAM/5-FU) was prepared and used as a conjugate system for delivering drugs to target E6 and E7 oncoproteins, which are predominant in cervical cancers. Specifically, molecular docking analysis was used to investigate the interaction between the PAMAM/5-FU and E6/E7 oncoproteins, which showed that the PAMAM/5-FU conjugate had a higher affinity for the oncoprotein than for 5-FU. Different generations of PAMAM dendrimers (0.5G, 1.0G, 1.5G, 2.0G, and 2.5G) were synthesized, characterized and tested as drug carriers for 5-FU. The PAMAM and PAMAM/5-FU drug conjugate showed less toxicity over COS-7 and HeLa cell lines. Laser confocal imaging and western blotting for tumor suppressor proteins pRb and p53 were used to confirm the interaction of PAMAM/5-FU with E6/E7 oncoproteins. Hematological analysis of PAMAM/5-FU using BALB/c female mice with cervical cancer confirmed the less toxic nature of this material. Based on these results, the developed PAMAM/5-FU conjugate is a potential candidate for the treatment of cervical cancer.

Capsular polysaccharides (CPS), a major virulence factor in Streptococcus pneumoniae, become thicker during blood invasion while not during asymptomatic nasopharyngeal colonization. However, the underlying mechanism controlling this differential pneumococcal CPS regulation remain unclear. Here, we show how VncR, the response regulator of the vancomycin resistance locus (vncRS operon), regulates CPS expression in vncR mutants in three serotype (type 2, 3, and 6B) backgrounds upon exposure to serum lactoferrin (LF). Comparative analysis of CPS levels in the wild type (WT) of three strains and their isogenic vncR mutants after LF exposure revealed a strain-specific alteration in CPS production. Consistently, VncR-mediated strain-specific CPS production is correlated with pneumococcal virulence, in vivo. Electrophoretic mobility-shift assay and co-immunoprecipitation revealed an interaction between VncR and the cps promoter (cpsp) in the presence of serum. In addition, in silico analysis uncovered this protein-DNA interaction, suggesting that VncR binds with the cpsp, and recognizes the strain-specific significance of the tandem repeats in cpsp. Taken together, the interaction of VncR and cpsp after serum exposure plays an essential role in regulating differential strain-specific CPS production, which subsequently determines strain-specific systemic virulence. This study highlights how host protein LF contributes to pneumococcal VncR-mediated CPS production. As CPS plays a significant role in immune evasion, these findings suggest that drugs designed to interrupt the VncR-mediated CPS production could help to combat pneumococcal infections.

Wnt signaling is one of the important pathways to play a major role in various biological processes, such as embryonic stem-cell development, tissue regeneration, cell differentiation, and immune cell regulation. Recent studies suggest that Wnt signaling performs an essential function in immune cell modulation and counteracts various disorders. Nonetheless, the emerging role and mechanism of action of this signaling cascade in immune cell regulation, as well as its involvement in various cancers, remain debatable. The Wnt signaling in immune cells is very diverse, e.g., the tolerogenic role of dendritic cells, the development of natural killer cells, thymopoiesis of T cells, B-cell-driven initiation of T-cells, and macrophage actions in tissue repair, regeneration, and fibrosis. The purpose of this review is to highlight the current therapeutic targets in (and the prospects of) Wnt signaling, as well as the potential suitability of available modulators for the development of cancer immunotherapies. Although there are several Wnt inhibitors relevant to cancer, it would be worthwhile to extend this approach to immune cells.

The built-in innate immunity in the human body combats various diseases and their causative agents. One of the components of this system is Toll-like receptors (TLRs), which recognize structurally conserved molecules derived from microbes and/or endogenous molecules. Nonetheless, under certain conditions, these TLRs become hypofunctional or hyperfunctional, thus leading to a disease-like condition because their normal activity is compromised. In this regard, various small-molecule drugs and recombinant therapeutic proteins have been developed to treat the relevant diseases, such as rheumatoid arthritis, psoriatic arthritis, Crohn’s disease, systemic lupus erythematosus, and allergy. Some drugs for these diseases have been clinically approved; however, their efficacy can be enhanced by conventional or targeted drug delivery systems. Certain delivery vehicles such as liposomes, hydrogels, nanoparticles, dendrimers, or cyclodextrins can be employed to enhance the targeted drug delivery. This review summarizes the TLR signaling pathway, associated diseases and their treatments, and the ways to efficiently deliver the drugs to a target site.

Background: TLRs are some of the actively pursued drug-targets in immune disorders. Owing to a recent surge in the cognizance of TLR structural biology and signalling pathways, numerous therapeutic modulators, ranging from low-molecular-weight organic compounds to polypeptides and nucleic acid agents have been developed. Methods: A penetratin-conjugated small peptide (TIP3), derived from the core β-sheet of TIRAP, was evaluated in vitro by monitoring the TLR-mediated cytokine induction and quantifying the protein expression using western blot. The therapeutic potential of TIP3 was further evaluated in TLR-dependent in vivo disease models. Findings: TIP3 blocks the TLR4-mediated cytokine production through both the MyD88- and TRIF-dependent pathways. A similar inhibitory-effect was exhibited for TLR3 but not on other TLRs. A profound therapeutic effect was observed in vivo, where TIP3 successfully alleviated the inflammatory response in mice model of collagen-induced arthritis and ameliorated the disease symptoms in psoriasis and SLE models. Interpretation: Our data suggest that TIP3 may be a potential lead candidate for the development of effective therapeutics against TLR-mediated autoimmune disorders. Funding: This work was supported by the National Research Foundation of Korea (NRF-2019M3A9A8065098, 2019M3D1A1078940 and 2019R1A6A1A11051471). The funders did not have any role in the design of the present study, data collection, data analysis, interpretation, or the writing of the manuscript. Keywords: Antagonist, TLR4, Collagen-induced arthritis, Systemic lupus erythematosus, Psoriasis, Decoy peptide

Long-term peritoneal dialysis is associated with progressive fibrosis of the peritoneum. Epithelial-mesenchymal transition (EMT) of mesothelial cells is an important mechanism involved in peritoneal fibrosis, and TGF-β1 is considered central in this process. However, targeting currently known TGF-β1-associated pathways has not proven effective to date. Therefore, there are still gaps in understanding the mechanisms underlying TGF-β1-associated EMT and peritoneal fibrosis. We conducted network-based integrated analysis of transcriptomic and proteomic data to systemically characterize the molecular signature of TGF-β1-stimulated human peritoneal mesothelial cells (HPMCs). To increase the power of the data, multiple expression datasets of TGF-β1-stimulated human cells were employed, and extended based on a human functional gene network. Dense network sub-modules enriched with differentially expressed genes by TGF-β1 stimulation were prioritized and genes of interest were selected for functional analysis in HPMCs. Through integrated analysis, ECM constituents and oxidative stress-related genes were shown to be the top-ranked genes as expected. Among top-ranked sub-modules, TNFAIP6, ZC3H12A, and NNT were validated in HPMCs to be involved in regulation of E-cadherin, ZO-1, fibronectin, and αSMA expression. The present data shows the validity of network-based integrated analysis in discovery of novel players in TGF-β1-induced EMT in peritoneal mesothelial cells, which may serve as new prognostic markers and therapeutic targets for peritoneal dialysis patients.

Immune cells of the myeloid and lymphoid lineages express Toll-like receptors (TLRs) to recognize pathogenic components or cellular debris and activate the immune system through the secretion of cytokines. Cytokines are signaling molecules that are structurally and functionally distinct from one another, although their secretion profiles and signaling cascades often overlap. This situation gives rise to pleiotropic cell-to-cell communication pathways essential for protection from infections as well as cancers. Nonetheless, deregulated signaling can have detrimental effects on the host, in the form of inflammatory or autoimmune diseases. Because cytokines are associated with numerous autoimmune and cancerous conditions, therapeutic strategies to modulate these molecules or their biological responses have been immensely beneficial over the years. There are still challenges in the regulation of cytokine function in patients, even in those who take approved biological therapeutics. In this review, our purpose is to discuss the differential expression patterns of TLR-regulated cytokines and their cell type specificity that is associated with cancers and immune-system-related diseases. In addition, we highlight key structural features and molecular recognition of cytokines by receptors; these data have facilitated the development and approval of several biologics for the treatment of autoimmune diseases and cancers.

Despite being crucial for combating microbes, paradoxical Toll-like receptors (TLRs) signaling have been associated with the aggravation of multiple immune disorders such as systemic lupus erythematosus, psoriasis, rheumatoid arthritis, and nonalcoholic steatohepatitis. The stoichiometry and precise arrangement of the interaction of adapters (via their Toll/interleukin-1 receptor [TIR] domains) are indispensable for the activation of TLRs and of downstream signaling cascades. Among adapters, plasma membrane-anchored MyD88 adaptor-like (MAL) has the potential for BB-loop-mediated self-oligomerization and interacts with other TIR domain-containing adaptors through αC and αD helices. Here, we used information on the MAL-αC interface to exploit its pharmacophores and to design a decoy peptide (MIP2) with broad-range TLR-inhibitory abilities. MIP2 abrogated MyD88- and TRIF-dependent lipopolysaccharide (LPS)-induced TLR4 signaling in murine and human cell lines and manifested a therapeutic potential in models of psoriasis, systemic lupus erythematosus, nonalcoholic steatohepatitis, and sepsis. Levels of hallmark serological and histological biomarkers were significantly restored and the disease symptoms were substantially ameliorated by MIP2 treatment of the animals. Collectively, our biophysical, in vitro, and in vivo findings suggest that MIP2 has broad specificity for TLRs and may be effective in modulating autoimmune complications caused by microbial or environmental factors.