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A novel chemoselective peptide conjugation via late-stage N-alkylation of pyridyl-alanine (PAL) in the solution and solid phase, namely, NAP, is demonstrated. The method constructs functionally diverse and highly stable N-alkylated conjugates with various peptides. Notably, conjugations in the solid phase offered a more economical process. The method can provide the opportunity for dual labeling along with a cysteine handle in a peptide chain. Finally, we showcased that the antiproliferative activities of the p53 peptide (MDM2 inhibitor) could be 2-fold enhanced via NAP conjugation with the RGD peptide (selective integrin binder).

•A single-chain CD38 T-cell engager targets CD38-negative LSCs activated by IFN-γ and induces CD38 expression on AML blasts.•CD38 T-cell engager activates T cells against autologous leukemia cells and in AML mouse models.

Peptide drugs often accompany epimeric impurities (isomers). Therefore, efficient chemical synthesis of epimers is critical to identify them correctly and investigate their biological activities. Here, we report the rapid synthesis and structure–activity relationship (SAR) studies of eight possible epimers of a somatostatin synthetic analog (SSA), lanreotide (LAN). SPPS and the subsequent on-resin rapid disulfide closure method offered >90% conversion yield for all epimers (P1–P8). Further, we developed an analytical method to separate these epimers, which enabled the profiling of five epimeric impurities in the API, purchased for Somatuline generic formulations. In SAR studies, most LAN epimers revealed compromised antiproliferative activity, while the P7epimer retained antiproliferative activity similar to LAN API, as supported by in silicoSAR studies in detail. Additionally, P7showed serum stability nearly identical to LAN, suggesting that drug epimers could be a potential API. Current studies will further encourage the development of novel SSA scaffolds.

ABSTRACTMore than 1 million Rohingya have fled Myanmar to live in Bangladesh, mostly in Cox’s Bazar district. The government of Bangladesh has been praised worldwide for sheltering them, but this enormous influx has strained its limited resources. As the host communities struggle with the Rohingya for control over, and access to, the scarce natural resources on which they depend for their livelihood – land, water, agriculture and forests – tension and conflict arises. The host community members perceive that the government and aid agencies prioritise the Rohingya over them in allocating resources, exacerbating their resentment. Both the locals and the Rohingya are marginalised, and therefore there is a need to focus on refugee–host community resource-based conflicts and related issues before designing any policy catering to the refugees.

ABSTRACTThe Shor people are protesting the ongoing mining of coal in the southern Kemerovo region of Siberia, while the Izhma Komi people are contesting the extraction of oil in the northern Komi Republic (Northwestern Federal District). The theory of “political opportunities” states that movements emerge when opportune moments create spaces for these, but we argue that in illiberal spaces, movements emerge against “threats” in an ever-decreasing political space. We argue that the extraction of coal and oil in Russia’s eastern regions poses not only structural threats – economic problems, public health/environmental decline, erosion of rights, and state repression – to its Indigenous peoples, but also cultural threats to their livelihoods and life-worlds. The various structural threats are thus intertwined with cultural threats in the case of Indigenous rights movements, and environmental decline is inextricably bound with the erosion of rights.

Here we report a highly efficient disulfide-driven peptide macrocyclization in 15 min on a solid support using persulfate as a crucial additive in iodine-mediated oxidative cyclization. The method eliminates the side products of classical iodine-mediated peptide cyclization. It is operationally simple and convenient for cyclizing small to lengthier peptides embodying popular cysteine building blocks in a single step.

This paper investigates energy harvesting using piezoelectric elements by exploiting the angular speed variation in high-speed rotating blades. The angular speed of high-speed rotating blades can vary randomly by a small amount depending on the requirement in an application. This variation in angular speed causes a random variation in the centrifugal force. An assembly of piezoelectric cantilever beam connected along the length of a rotating blade can experience variable bending stress due to this variable centrifugal force and can convert the mechanical energy to electrical energy by utilizing its sensing property. For a typical specification, the proposed energy harvester can produce a maximum power of 190 nW. This harvested power can be significantly increased by installing several piezoelectric energy harvesters in each rotating blade. The feasibility of the proposed concept is verified with prototype and experimental results.

Site-selective chemical modification of protein side chain has probed enormous opportunities in the fundamental understanding of cellular biology and therapeutic applications. Primarily, in the field of biopharmaceuticals, the formulation of bioconjugates has been found to have more potential than an individual constituent. In this regard, Lysine and Cysteine are the most widely used endogenous amino acid for these purposes. Recently, the aromatic side chain residues (Trp, Tyr, and His) that are low abundant in protein have gained more attention in therapeutic applications due to their advantages of chemical reactivity and specificity. This review discusses the site-selective bioconjugation methods for aromatic side chains (Trp, Tyr and His) and highlights the developed strategies in the last three years, along with their applications. Also, the review highlights the prevalent methods published earlier. We have examined that metal-catalyzed and photocatalytic reactions are gaining more attention for bioconjugation, though their practical operation is under development. The review has been summarized with the future perspective of protein and peptide conjugations contemplating therapeutic applications and challenges.

Outcomes after CART cell therapy in myeloma is not well known in the literature and the question of whether subsequent immune engager therapies (IET) are efficacious due to T cell exhaustion also remain. Hence, we examined the outcomes of patients post ide-cel, and characterized relapses, therapies, and Progression free survival (PFS) PFS-1, PFS-2 in a real-world setting.

Daratumumab (Dara), a multiple myeloma (MM) therapy, is an antibody against the surface receptor CD38, which is expressed not only on plasma cells but also on NK cells and monocytes. Correlative data have highlighted the immune-modulatory role of Dara, despite the paradoxical observation that Dara regimens decrease the frequency of total NK cells. Here we show that, despite this reduction, NK cells play a pivotal role in Dara anti-MM activity. CD38 on NK cells is essential for Dara-induced immune modulation, and its expression is restricted to NK cells with effector function. We also show that Dara induces rapid CD38 protein degradation associated with NK cell activation, leaving an activated CD38-negative NK cell population. CD38+ NK cell targeting by Dara also promotes monocyte activation, inducing an increase in T-cell costimulatory molecules (CD86/80) and enhancing anti-MM phagocytosis activity ex vivo and in vivo. In support of Dara’s immunomodulating role, we show that MM patients that discontinued Dara therapy because of progression maintain targetable unmutated surface CD38 expression on their MM cells, but retain effector cells with impaired cellular immune function. In summary, we report that CD38+ NK cells may be an unexplored therapeutic target for priming the immune system of MM patients.

18F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is one of the most widely used imaging techniques to detect multiple myeloma (MM). Intracellular FDG uptake depicts in vivo metabolic activity, which can be seen in both malignant and nonmalignant cells, resulting in limited sensitivity and specificity. Our group showed preclinically that tracing MM dissemination using a CD38-directed human antibody, daratumumab, that is radioconjugated with 64Cu via the chelator DOTA (64Cu-daratumumab), led to improved sensitivity and specificity over that of FDG. Here, we report the results of a phase 1 trial designed to (1) assess the safety and feasibility of 64Cu-daratumumab PET/CT and (2) preliminarily evaluate and characterize the ability of 64Cu-daratumumab to accurately detect or exclude MM lesions. A total of 12 daratumumab-naive patients were imaged. Prior to the injection of 15 mCi/5 mg of 64Cu-daratumumab, patients were treated with 0 (n = 3), 10 (n = 3), 45 (n = 3), or 95 mg (n = 3) of unlabeled daratumumab to assess its effect on image quality. No significant adverse events were observed from either unlabeled daratumumab or 64Cu-daratumumab. Of the dose levels tested, 45 mg unlabeled daratumumab was the most optimal in terms of removing background signal without saturating target sites. 64Cu-daratumumab PET/CT provided safe whole-body imaging of MM. A trial comparing the sensitivity and specificity of 64Cu-daratumumab PET/CT with that of FDG PET/CT is planned. This trial was registered at www.clinicaltrials.gov as #NCT03311828.

18F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is one of the most widely used imaging techniques to detect multiple myeloma (MM). Intracellular FDG uptake depicts in vivo metabolic activity, which can be seen in both malignant and nonmalignant cells, resulting in limited sensitivity and specificity. Our group showed preclinically that tracing MM dissemination using a CD38-directed human antibody, daratumumab, that is radioconjugated with 64Cu via the chelator DOTA (64Cu-daratumumab), led to improved sensitivity and specificity over that of FDG. Here, we report the results of a phase 1 trial designed to (1) assess the safety and feasibility of 64Cu-daratumumab PET/CT and (2) preliminarily evaluate and characterize the ability of 64Cu-daratumumab to accurately detect or exclude MM lesions. A total of 12 daratumumab-naive patients were imaged. Prior to the injection of 15 mCi/5 mg of 64Cu-daratumumab, patients were treated with 0 (n = 3), 10 (n = 3), 45 (n = 3), or 95 mg (n = 3) of unlabeled daratumumab to assess its effect on image quality. No significant adverse events were observed from either unlabeled daratumumab or 64Cu-daratumumab. Of the dose levels tested, 45 mg unlabeled daratumumab was the most optimal in terms of removing background signal without saturating target sites. 64Cu-daratumumab PET/CT provided safe whole-body imaging of MM. A trial comparing the sensitivity and specificity of 64Cu-daratumumab PET/CT with that of FDG PET/CT is planned. This trial was registered at www.clinicaltrials.govas #NCT03311828.

We report the case of an 88-year-old man with coronavirus disease 2019 (COVID-19) who presented with ARDS and septic shock. The patient had exquisite BP sensitivity to low-dose angiotensin II (Ang-2), allowing for rapid liberation from high-dose vasopressors. We hypothesize that sensitivity to Ang-2 might be related to biological effect of severe acute respiratory syndrome coronavirus 2 infection. The case is suggestive of a potential role for synthetic Ang-2 for patients with COVID-19 and septic shock. Further studies are needed to confirm our observed clinical efficacy.

Introduction: Bispecific antibodies (BisAb) are effective therapies for relapsed myeloma yet associated with high risk of potentially severe infections. A prior study from our center did not associate any baseline characteristics with 90-day risk of infection. In clinical practice patients are already receiving sequential immune effector cell therapy (IET; BisAb or CAR T) it remains unclear whether this compounds the infectious risk. Herein, we examined whether a prior T-cell redirecting therapy predisposes to increased risk of infection during subsequent BisAb.

Leukemia stem cells (LSCs), enriched in the CD34+CD38- AML population, are considered the main drivers of relapse in acute myeloid leukemia (AML). While more differentiated progenitors and bulk AML blasts reside in the CD34+CD38+ fraction, targeting CD38 in AML is less pursued, as LSCs are mainly CD38-. We show IFNγ (10 ng/ml) induced an increase in CD38 mRNA (mean fold change IFNγ over vehicle = 7.7, p=0.03, n=3) and surface CD38 (mean CD38 High% population IFNγ 56%±17 vs vehicle 16%±10, p<0.0001) in both CD34+ and CD34- AML primary blasts, and decreased the clonogenic activities of primary AML cells (colony forming unit IFNγ 50±36 vs vehicle 216±117, p=0.002, n=4) regardless of cytogenetics. scRNA and total RNA sequencing data in CD34+ AML primary blasts showed that upon IFNγ treatment, CD38 and Interferon Regulatory Factor 1 (IRF-1) were consistently the most upregulated genes compared to vehicle (>2.5 Log 2Fold Change; p=0; FDR=0). Furthermore, gene set enrichment analysis (FDR=0) indicated IFNγ induced an upregulation of genes involved in apoptosis and DNA repair, and a suppression of genes in the pro-oncogenic Wnt beta catenin pathways. CD38 luciferase-based reporter assays, chromatin immunoprecipitation, and IRF-1 knockdown experiments in AML cells showed that, upon IFNγ treatment, IRF1 is pivotal in CD38 transcriptional regulation.

The use of immune checkpoint inhibitors has markedly improved the survival outcomes of many patients with solid tumors. However, in multiple myeloma (MM), the use of such inhibitors has failed to achieve survival benefit. We previously showed that oncolytic herpes simplex virus 1 (oHSV-1) can effectively infect MM cells and induce apoptosis through the receptors for oHSV-1, NECTIN-1 and HVEM (herpes virus entry mediator). HVEM, a member of the TNF receptor superfamily (TNFRSF14), is an immune checkpoint present on T cells, B cells, NK cells and macrophages. Depending on HVEM's interaction with its major inhibitory ligand, B- and T-lymphocyte attenuator (BTLA) or its major activating ligand, tumor necrosis factor superfamily member 14 (TNFSF14, LIGHT), it is pivotal in downmodulating or stimulating the immune cells. Accordingly, targeting HVEM to block its interaction with BTLA is an area of therapeutic interest.

Gum of Buchanania lanzanSpreng. (Anacardiaceae) is being traditionally used for various medicinal purposes. This study evaluates the phytochemicals as also the physico-chemical properties and antioxidant activity in gum exudates of B. lanzanSpreng. Seven samples of gum exudates of B. lanzanSpreng. were collected from Bilaspur (Chhattisgarh), Simdega and IINRG farm (Jharkhand), Dindori and Umaria (Madhya Pradesh) and Mirzapur (Uttar Pradesh) for studying variations in their major phytochemicals, physico-chemical properties and antioxidant activity adopting standard procedures. Twenty percent and ten percent concentrations of gum exudates were used for determining their viscosity (cP) at ambient temperature. The antioxidant potential of the gum exudates was evaluated by free radical scavenging activity using 1,1-diphenyl-2-picryl hydrazyl assay. Flavonoids, saponin, amino acid/protein and carbohydrates were found in all the gum exudates. All of them showed intra-specific variation in the physico-chemical properties viz. moisture level, color parameters (L, a, b), ash content, elemental (CHN) level, specific rotation [α] and heavy metals. Tannin was present only in the black gum exudates collected from Madhya Pradesh and Chhattisgarh. B. lanzangum exudates, at twenty percent and ten percent concentrations, exhibited shear thinning/pseudoplastic flow pattern in their viscosity. Antioxidant activity was found only in samples with tannin and the magnitude was related to the tannin level in the gum. The findings show the significant qualitative and quantitative intra-specific variations in B. lanzangum exudates, collected from different places, for their phytochemicals, physico-chemical properties and antioxidant activity.

•Artisanal and small scale mining of coloured gemstones is prevalent in the Kalahandi district of Western Odisha, in India.•Mainly indigenous Khond people and the so called scheduled caste labours work in these mines.•Kalahandi is historically characterised by drought, failing agriculture, and oppressive feudal social structure.•Gem mining has increased after the liberalisation of gems and jewellery sector of Indian economy since 1990’s.•These conditions are leading to De-peasantisation and De-agrarianization in Kalahandi.

Procyclic Trypanosoma brucei cells were synchronized with 0.2 mM hydroxyurea. The cells did not arrest at the G1/S boundary but proceeded through one round of replication and arrested near the end of S phase. The mitochondrial genome (kinetoplast DNA network) replicated, forming two progeny networks, but the repair of minicircle gaps was inhibited.

ABSTRACTProcyclic Trypanosoma bruceicells were synchronized with 0.2 mM hydroxyurea. The cells did not arrest at the G1/S boundary but proceeded through one round of replication and arrested near the end of S phase. The mitochondrial genome (kinetoplast DNA network) replicated, forming two progeny networks, but the repair of minicircle gaps was inhibited.

Current biomedical research has its focus on the search for newer intervention strategies to control public health impact of parasitic diseases. The dramatic advances of molecular and cellular biology in recent times have provided opportunities for discovering and evaluating molecular targets for drug designing, which now form a rational basis for the development of improved anti parasitic therapy. DNA topoisomerases, the “cellular magicians” involved in nearly all biological processes governing DNA, have emerged as one such biological target. Over the last two decades, interest in topoisomerases has expanded beyond the realm of the basic science laboratory into the clinical arena. This review aims at providing a comprehensive insight into the biology of DNA topoisomerases and also focus on its evolution as a drug target in the unicellular kinetoplastids.

Leishmaniasis is the second-most dreaded parasitic disease in the modern world, behind malaria. The lack of effective vaccines demand improved chemotherapy along with the development of lead compounds and newer targets. We report here that the pentacyclic triterpenoid, dihydrobetulinic acid (DHBA), is a novel lead compound for antileishmanial therapy. It acts by targeting DNA topoisomerases. DNA topoisomerase I and II activity was studied using relaxation and decatenation assays. Mechanistic studies were based on the decreased mobility of enzyme-bound DNA compared with free DNA and the differential mobility of nicked and supercoiled monomers in 1% agarose gel. Pulsed field gradient gel electrophoresis, confocal microscopy, and transmission electron microscopy were performed to assess cytotoxicity of the compound and ultrastructural damage of the parasite. Apoptosis was studied by the isolation of DNA from DHBA-treated parasites and subsequent electrophoresis in 1% agarose gel. DHBA inhibits growth of Leishmania donovanipromastigotes and amastigotes with an IC50of 2.6 and 4.1 µM respectively. The compound is a dual inhibitor of DNA topoisomerases that fails to induce DNA cleavage and acts by preventing the formation of enzyme-DNA binary complex, ultimately inducing apoptosis. Treatment of infected golden hamsters with the compound markedly reduces (> 92%) parasitic burden, both in spleen and liver. Interestingly, the 17-decarboxylated analogue, dihydrolupeol, does not inhibit DNA topoisomerase I and II, has no effect on parasitic growth, and also fails to induce apoptosis. DHBA is a potent antileishmanial agent that induces apoptosis by primarily targeting DNA topoisomerases. Therefore it is a strong candidate for use in designing new antileishmanial drugs.

Luteolin, a naturally occurring flavonoid, is abundant in our daily dietary intake. It exhibits a wide spectrum of pharmacological properties, but little is known about its biochemical targets other than the fact that it induces topoisomerase II-mediated apoptosis. In the present study, we show that luteolin completely inhibits the catalytic activity of eukaryotic DNA topoisomerase I at a concentration of 40μM, with an IC50 of 5μM. Preincubation of enzyme with luteolin before adding a DNA substrate increases the inhibition of the catalytic activity (IC50 = 0.66μM). Treatment of DNA with luteolin before addition of topoisomerase I reduces this inhibitory effect. Subsequent fluorescence tests show that luteolin not only interacts directly with the enzyme but also with the substrate DNA, and intercalates at a very high concentration (>250μM) without binding to the minor groove. Direct interaction between luteolin and DNA does not affect the assembly of the enzyme–DNA complex, as evident from the electrophoretic mobility-shift assays. Here we show that the inhibition of topoisomerase I by luteolin is due to the stabilization of topoisomerase-I DNA-cleavable complexes. Hence, luteolin is similar to camptothecin, a class I inhibitor, with respect to its ability to form the topoisomerase I-mediated ‘cleavable complex'. But, unlike camptothecin, luteolin interacts with both free enzyme and substrate DNA. The inhibitory effect of luteolin is translated into concanavalin A-stimulated mouse splenocytes, with the compound inducing SDS–K+-precipitable DNA–topoisomerase complexes. This is the first report on luteolin as an inhibitor of the catalytic activity of topoisomerase I, and our results further support its therapeutic potential as a lead anti-cancer compound that poisons topoisomerases.

Background: Plant-derived flavonoids, which occur abundantly in our daily dietary intake, possess antitumor, antibacterial, and free radical scavenging properties. They form active constituents of a number of herbal and traditional medicines. Several flavonoids have been shown to exert their action by interacting with DNA topoisomerases and promoting site-specific DNA cleavage. Therefore, flavonoids are potential candidates in drug design. We report here that, although the flavonoids luteolin and quercetin are potent antileishmanial agents, luteolin has great promise for acting as a lead compound in the chemotherapy of leishmaniasis, a major concern in developing countries. Materials and Methods: Kinetoplast DNA (kDNA) minicircle cleavage in drug-treated parasites was measured by electrophoresis of the total cellular DNA, followed by Southern hybridization using 32P labeled kDNA as a probe. Cell cycle progression and apoptosis were measured by flow cytometry using propidium iodide and fluorescein isothiocyanate (FITC)-labeled Annexin V. Results: Luteolin and quercetin inhibited the growth of Leishmania donovanipromastigotes and amastigotes in vitro, inhibited DNA synthesis in promastigotes, and promoted topoisomerase-II-mediated linearization of kDNA minicircles. The IC50values of luteolin and quercetin were 12.5 µM and 45.5 µM, respectively. These compounds arrest cell cycle progression in L. donovanipromastigotes, leading to apoptosis. Luteolin has no effect on normal human T-cell blasts. Both luteolin and quercetin reduced splenic parasite burden in animal models. Conclusion: Luteolin and quercetin are effective antileishmanial agents. Quercetin has nonspecific effects on normal human T cells, but luteolin appears nontoxic. So, luteolin can be a strong candidate for antileishmanial drug design.

Introduction: 18Fluoro-deoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is one of the most widely used imaging techniques to detect multiple myeloma (MM). Intracellular FDG uptake depicts in vivometabolic activity, which can be seen in both malignant and non-malignant cells, resulting in limited sensitivity and specificity. Our group showed preclinically that tracing MM dissemination using a CD38-directed human antibody, daratumumab, that is radioconjugated with copper-64 via the chelator DOTA (64Cu-DOTA-Dara), led to improved sensitivity and specificity over that of FDG (Caserta et al, Blood 2018). Herein, we report the results of a Phase 1 trial (NCT#03311828) designed to 1) assess the safety and feasibility of 64Cu-DOTA-Dara PET/CT and 2) to evaluate and characterize the ability of 64Cu-DOTA-Dara to accurately detect or exclude MM lesions compared with FDG PET/CT.

Krishnan: Celgene, Janssen, Sanofi, BMS: Consultancy; Sutro BioPharma, zPredicta: Consultancy; Amgen, Takeda: Speakers Bureau; Celgene, Z Predicta: Other: Stock Ownership; Takeda: Research Funding. Palmer:Gilead Sciences: Consultancy. Rosenzweig:Celgene, Takeda: Speakers Bureau. Wu:ImaginAb, Inc.: Consultancy, Other: Board Member.