Contribution of Coronavirus-Specific Immunoglobulin G Responses to Complement Overactivation in Patients with Severe Coronavirus Disease 2019.

BACKGROUND: Excessive complement activation has been implicated in the pathogenesis of coronavirus disease 2019 (COVID-19), but the mechanisms leading to this response remain unclear. METHODS: We measured plasma levels of key complement markers, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antibodies against SARS-CoV-2 and seasonal human common cold coronaviruses (CCCs) in hospitalized patients with COVID-19 of moderate (n = 18) and critical severity (n = 37) and in healthy controls (n = 10). RESULTS: We confirmed that complement activation is systemically increased in patients with COVID-19 and is associated with a worse disease outcome. We showed that plasma levels of C1q and circulating immune complexes were markedly increased in patients with severe COVID-19 and correlated with higher immunoglobulin (Ig) G titers, greater complement activation, and higher disease severity score. Additional analyses showed that the classical pathway was the main arm responsible for augmented complement activation in severe patients. In addition, we demonstrated that a rapid IgG response to SARS-CoV-2 and an anamnestic IgG response to the nucleoprotein of the CCCs were strongly correlated with circulating immune complex levels, complement activation, and disease severity. CONCLUSIONS: These findings indicate that early, nonneutralizing IgG responses may play a key role in complement overactivation in severe COVID-19. Our work underscores the urgent need to develop therapeutic strategies to modify complement overactivation in patients with COVID-19.

Adalimumab Immunogenicity Is Negatively Correlated with Anti-Hinge Antibody Levels in Patients with Rheumatoid Arthritis.

Patients with rheumatoid arthritis (RA) are frequently treated with anti-tumor necrosis factor-α immunoglobulin therapy but develop neutralizing antibodies against these drugs, necessitating therapeutic monitoring of drug concentrations and anti-drug antibodies. Patients with RA have multiple factors related to their autoimmune disposition that interfere with conventionally used methods to detect anti-drug antibodies. Currently deployed analytical methods have significant limitations that hinder clinical interpretation and/or routine use, and no method can detect immunogenicity and drug levels simultaneously to provide clinically meaningful recommendations. Given these limitations, the objective of this study was to identify sources of and associations with assay interference in patients with RA. We designed a modular immunogenicity and drug concentration detection technology to identify the factors that interfere with the detection of adalimumab and anti-adalimumab antibodies in a cohort of 206 patients with RA. Patients were included from the University of Pittsburgh Rheumatoid Arthritis Comparative Effectiveness Research registry. In this cohort, we analyzed clinical and plasma factors associated with anti-adalimumab and anti-hinge antibodies. A novel flow cytometry-based assay was developed and validated that simultaneously measures adalimumab and anti-adalimumab antibody concentrations, overcoming many of the interference factors that are limitations of conventional assays, including anti-fragment crystallizable (Fc) and anti-hinge antibodies. C-reactive protein (P = 0.035), Disease Activity Score-28 (DAS28) score (P = 0.002), and disease activity category (P = 0.009) were significantly associated with anti-adalimumab antibodies but not with anti-hinge antibodies (P > 0.05). Anti-hinge antibodies were inversely associated with drug-neutralizing antibodies (P = 0.002). In patients with RA, anti-hinge antibodies may have a potential protective effect against the development of anti-adalimumab antibodies. SIGNIFICANCE STATEMENT: Using a novel cytometric assay that simultaneously measures drug and anti-drug antibodies, we overcame many interferences that hinder the clinical interpretation of adalimumab immunogenicity testing. Our investigation in patients with RA demonstrated that immunogenicity impaired the pharmacological action of adalimumab via analysis of RA disease severity markers. We also demonstrate that patients with anti-hinge antibodies had lower anti-adalimumab antibody levels and decreased drug neutralization. Our results suggest that anti-hinge antibodies can predict adalimumab immunogenicity before the start of therapy.

Asparaginase immune complexes induce Fc-γRIII-dependent hypersensitivity in naive mice.

Asparaginase (ASNase) is an important drug for the treatment of leukemias. However, hypersensitivity to ASNase can increase the risk of leukemia relapse. Two mechanisms of ASNase hypersensitivity have been identified in mice. The existence of a pathway involving anti-ASNase IgG and Fc-γ receptor III (Fc-γRIII) implies that IgG and ASNase immune complexes (ICs) could directly induce hypersensitivity. The aim of this study was to detect ASNase ICs in mice after hypersensitivity reactions and determine their role in hypersensitivity. Protein G beads were used to detect plasma ASNase ICs by flow cytometry. Anti-ASNase IgG was purified from the plasma of sensitized mice, and ASNase ICs were prepared ex vivo at various ratios of ASNase to anti-ASNase IgG. The levels of ASNase ICs detected after hypersensitivity reactions correlated with reaction severity (R2 = 0.796; P = 0.0005). ASNase ICs prepared ex vivo required high levels of anti-ASNase IgG for formation, and binding to naive and sensitized immune cells depended on soluble anti-ASNase IgG, antigen:antibody ratio, and Fc-γRIII. Similarly, basophil activation by ASNase ICs depended on the antigen:antibody ratio and Fc-γRIII. Consistent with the ex vivo results, naive mice receiving ASNase ICs developed hypersensitivity reactions. Our data demonstrate that ASNase ICs can directly contribute to the onset and severity of ASNase hypersensitivity.-Rathod, S., Ramsey, M., DiGiorgio, D., Berrios, R., Finkelman, F. D., Fernandez, C. A. Asparaginase immune complexes induce Fc-γRIII-dependent hypersensitivity in naive mice.

Hypersensitivity reactions to asparaginase in mice are mediated by anti-asparaginase IgE and IgG and the immunoglobulin receptors FcεRI and FcγRIII.

Asparaginase is an important drug for the treatment of leukemias. However, anti-asparaginase antibodies often develop, which can decrease asparaginase drug levels and increase the risk of relapse. The aim of this study is to identify the immunoglobulin isotypes and receptors responsible for asparaginase hypersensitivities. Mice immunized with asparaginase developed anti-asparaginase IgG1 and IgE antibodies, and challenging the sensitized mice with asparaginase induced severe hypersensitivity reactions. Flow cytometry analysis indicated that macrophages/monocytes, neutrophils, and basophils bind asparaginase ex vivo through FcγRIII. In contrast, asparaginase binding to basophils was dependent on FcγRIII and IgE. Consistent with the asparaginase binding data, basophil activation by asparaginase occurred via both IgG/FcγRIII and IgE/FcεRI. Depleting >95% of B cells suppressed IgG but not IgE-dependent hypersensitivity, while depleting CD4+ T cells provided complete protection. Combined treatment with either anti-IgE mAb plus a platelet-activating factor receptor antagonist or anti-FcγRIII mAb plus a H1 receptor antagonist suppressed asparaginase hypersensitivity. The observations indicate that asparaginase hypersensitivity is mediated by antigen-specific IgG and/or IgE through the immunoglobulin receptors FcγRIII and FcεRI, respectively. Provided that these results apply to humans, they emphasize the importance of monitoring both IgE- and IgG-mediated asparaginase hypersensitivities in patients receiving this agent.

In Vitro Analysis of Licorice (Glycyrrhiza glabra) Root Extract Activity on Streptococcus mutans in Comparison to Chlorhexidine and Fluoride Mouthwash.

AIM: The present study was done to determine the activity of licorice root extract on Streptococcus mutans (S. mutans) in comparison to chlorhexidine and fluoride mouthwash. MATERIALS AND METHODS: In the current study, the different concentrations of aqueous and ethanolic licorice root extract were subjected to microbiological assay and zone of inhibition was determined against S. mutans by agar ditch method. Minimum inhibitory concentration (MIC) of aqueous and ethanolic solution was obtained by using broth dilution method and agar dilution method. Chlorhexidine and fluoride mouthwash were kept as a positive control in the present study. One-way ANOVA along with Tukey post hoc test were used at 5% level of significance to analyze data. RESULTS: Mean zone of inhibition of chlorhexidine mouthwash, fluoride mouthwash, aqueous and ethanolic licorice root extracts against S. mutans at 24 hours were 23 mm, 14.2 mm, 15.8 mm and 22.4 mm, respectively. Minimum inhibitory concentration of aqueous and ethanolic licorice root extract on S. mutans was 20 mg/mL and 12.5 mg/mL, respectively by both broth dilution method and agar dilution method. CONCLUSION: The antibacterial effect produced by ethanolic licorice root extract on S. mutans was comparable to chlorhexidine mouthwash while significantly higher in comparison with aqueous form and fluoride mouthwash. CLINICAL SIGNIFICANCE: The interest in the plants with antibacterial and anti-inflammatory activity has increased now days to treat various dental diseases as consequences of current problems associated with the conventional agents. Licorice root is easily available, economically feasible and culturally acceptable and may possess minimal side effects as compared to conventional means of chemicotherapeutic agents used for reduction of S. mutans in oral cavity and hence can be recommended for prevention of dental caries.

Asparaginase-specific basophil recognition and activation predict Asparaginase hypersensitivity in mice.

Background: Asparaginase (ASNase) is a crucial part of acute leukemia treatment, but immune responses to the agent can reduce its effectiveness and increase the risk of relapse. Currently, no reliable and validated biomarker predicts ASNase-induced hypersensitivity reactions during therapy. We aimed to identify predictive biomarkers and determine immune cells responsible for anaphylaxis using a murine model of ASNase hypersensitivity. Methods: Our preclinical study uses a murine model to investigate predictive biomarkers of ASNase anaphylaxis, including anti-ASNase antibody responses, immune complex (IC) levels, ASNase-specific binding to leukocytes or basophils, and basophil activation. Results: Our results indicate that mice immunized to ASNase exhibited dynamic IgM, IgG, and IgE antibody responses. The severity of ASNase-induced anaphylaxis was found to be correlated with levels of IgG and IgE, but not IgM. Basophils from immunized mice were able to recognize and activate in response to ASNase ex vivo, and the extent of recognition and activation also correlated with the severity of anaphylaxis observed. Using a multivariable model that included all biomarkers significantly associated with anaphylaxis, independent predictors of ASNase-induced hypersensitivity reactions were found to be ASNase IC levels and ASNase-specific binding to leukocytes or basophils. Consistent with our multivariable analysis, we found that basophil depletion significantly protected mice from ASNase-induced hypersensitivity reactions, supporting that basophils are essential and can be used as a predictive marker of ASNase-induced anaphylaxis. Conclusions: Our study demonstrates the need for using tools that can detect both IC- and IgE-mediated hypersensitivity reactions to mitigate the risk of ASNase-induced hypersensitivity reactions during treatment.

Phenotyping of CAR T cells.

Adaptive immunotherapy has been growing as a therapeutic alternative for cancer and other diseases treatment; chimeric antigen receptor (CAR) T cells comprise a type of adaptive immunotherapy, with recombinant receptor constructs expressed in T cells to target cells expressing specific antigens, is a potential new treatment for blood cancers and solid tumors. The phenotypic, activation, and functional profile of infused CAR-T cells have been linked to the efficacy of CAR-T cell treatment. As a result, immunophenotypic characterization of CAR-T cells during the bioprocess is critical for controlling cell quality and, eventually, improving antitumor effectiveness. Therefore, we propose a flow cytometry based immunophenotyping analysis of CAR-T cells in this chapter to define the phenotype of CAR-T subsets.

T cells in the peritoneum.

The peritoneal cavity is a fluid-packed area that houses most of the abdominal organs, including the omentum, a visceral adipose tissue with milky patches or groups of leukocytes organized in the same way to those observed in typical lymphoid tissues. A distinct population of leukocytes patrols the peritoneal cavity and travels in and out of the milky spots, facing antigens or pathogens in the peritoneal fluid and responding appropriately. T cells may play a crucial function in regulating adaptive immune responses to antigens in the peritoneal cavity to ensure tissue homeostasis and healing. When peritoneal homeostasis is interrupted by inflammation, infection, obesity, or tumor metastasis, the omentum's dedicated fibroblastic stromal cells and mesothelial cells control peritoneal leukocyte recruitment and activation in unique ways. T cells, which employ their T cell receptor to target specific antigens, are an important component of the acquired immune response since they are present in the peritoneal cavity. The peritoneum provides a different environment for T cells to respond to pathogens. This chapter outlines the anatomy relevant to T cell function and biology, such as antigen processing/presentation, T cell activation, and the many T cell subpopulations in the peritoneal cavity, as well as their role in cancer or other infection.

Engineering a folic acid-decorated ultrasmall gemcitabine nanocarrier for breast cancer therapy: Dual targeting of tumor cells and tumor-associated macrophages.

Combination of passive targeting with active targeting is a promising approach to improve the therapeutic efficacy of nanotherapy. However, most reported polymeric systems have sizes above 100 nm, which limits effective extravasation into tumors that are poorly vascularized and have dense stroma. This will, in turn, limit the overall effectiveness of the subsequent uptake by tumor cells via active targeting. In this study, we combined the passive targeting via ultra-small-sized gemcitabine (GEM)-based nanoparticles (NPs) with the active targeting provided by folic acid (FA) conjugation for enhanced dual targeted delivery to tumor cells and tumor-associated macrophages (TAMs). We developed an FA-modified prodrug carrier based on GEM (PGEM) to load doxorubicin (DOX), for co-delivery of GEM and DOX to tumors. The co-delivery system showed small particle size of ∼10 nm in diameter. The ligand-free and FA-targeted micelles showed comparable drug loading efficiency and a sustained DOX release profile. The FA-conjugated micelles effectively increased DOX uptake in cultured KB cancer cells that express a high level of folate receptor (FR), but no obvious increase was observed in 4T1.2 breast cancer cells that have a low-level expression of FR. Interestingly, in vivo, systemic delivery of FA-PGEM/DOX led to enhanced accumulation of the NPs in tumor and drastic reduction of tumor growth in a murine 4T1.2 breast cancer model. Mechanistic study showed that 4T1.2 tumor grown in mice expressed a significantly higher level of FOLR2, which was selectively expressed on TAMs. Thus, targeting of TAM may also contribute to the improved in vivo targeted delivery and therapeutic efficacy.

Nanotechnology as a Shield against COVID-19: Current Advancement and Limitations.

The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global health problem that the WHO declared a pandemic. COVID-19 has resulted in a worldwide lockdown and threatened to topple the global economy. The mortality of COVID-19 is comparatively low compared with previous SARS outbreaks, but the rate of spread of the disease and its morbidity is alarming. This virus can be transmitted human-to-human through droplets and close contact, and people of all ages are susceptible to this virus. With the advancements in nanotechnology, their remarkable properties, including their ability to amplify signal, can be used for the development of nanobiosensors and nanoimaging techniques that can be used for early-stage detection along with other diagnostic tools. Nano-based protection equipment and disinfecting agents can provide much-needed protection against SARS-CoV-2. Moreover, nanoparticles can serve as a carrier for antigens or as an adjuvant, thereby making way for the development of a new generation of vaccines. The present review elaborates the role of nanotechnology-based tactics used for the detection, diagnosis, protection, and treatment of COVID-19 caused by the SARS-CoV-2 virus.

Amino Acid Metabolic Vulnerabilities in Acute and Chronic Myeloid Leukemias.

Amino acid (AA) metabolism plays an important role in many cellular processes including energy production, immune function, and purine and pyrimidine synthesis. Cancer cells therefore require increased AA uptake and undergo metabolic reprogramming to satisfy the energy demand associated with their rapid proliferation. Like many other cancers, myeloid leukemias are vulnerable to specific therapeutic strategies targeting metabolic dependencies. Herein, our review provides a comprehensive overview and TCGA data analysis of biosynthetic enzymes required for non-essential AA synthesis and their dysregulation in myeloid leukemias. Furthermore, we discuss the role of the general control nonderepressible 2 (GCN2) and-mammalian target of rapamycin (mTOR) pathways of AA sensing on metabolic vulnerability and drug resistance.

Mechanistic studies of PEG-asparaginase-induced liver injury and hepatic steatosis in mice.

PEGylated-l-asparaginase (PEG-ASNase) is a chemotherapeutic agent used to treat pediatric acute lymphoblastic leukemia (ALL). Its use is avoided in adults due to its high risk of liver injury including hepatic steatosis, with obesity and older age considered risk factors of the injury. Our study aims to elucidate the mechanism of PEG-ASNase-induced liver injury. Mice received 1500 U/kg of PEG-ASNase and were sacrificed 1, 3, 5, and 7 days after drug administration. Liver triglycerides were quantified, and plasma bilirubin, ALT, AST, and non-esterified fatty acids (NEFA) were measured. The mRNA and protein levels of genes involved in hepatic fatty acid synthesis, ß-oxidation, very low-density lipoprotein (VLDL) secretion, and white adipose tissue (WAT) lipolysis were determined. Mice developed hepatic steatosis after PEG-ASNase, which associated with increases in bilirubin, ALT, and AST. The hepatic genes Ppara, Lcad/Mcad, Hadhb, Apob100, and Mttp were upregulated, and Srebp-1c and Fas were downregulated after PEG-ASNase. Increased plasma NEFA, WAT loss, and adipose tissue lipolysis were also observed after PEG-ASNase. Furthermore, we found that PEG-ASNase-induced liver injury was exacerbated in obese and aged mice, consistent with clinical studies of ASNase-induced liver injury. Our data suggest that PEG-ASNase-induced liver injury is due to drug-induced lipolysis and lipid redistribution to the liver.

Assessing seropositivity for IgG antibodies against SARS-CoV-2 in Ahmedabad city of India: a cross-sectional study.

OBJECTIVES: To study the percentage seropositivity for SARS-CoV-2 to understand the pandemic status and predict the future situations in Ahmedabad. STUDY DESIGN: Cross-sectional study. SETTINGS: Field area of Ahmedabad Municipal Corporation. PARTICIPANTS: More than 30 000 individuals irrespective of their age, sex, acute/past COVID-19 infection participated in the serosurvey which covered all the 75 Urban Primary Health Centres (UPHCs) across 48 wards and 7 zones of the city. Study also involved healthcare workers (HCWs) from COVID-19/non-COVID-19 hospitals. INTERVENTIONS: Seropositivity of IgG antibodies against SARS-CoV-2 was measured as a mark of COVID-19 infection. PRIMARY AND SECONDARY OUTCOMES: Seropositivity was used to calculate cumulative incidence. Correlation of seropositivity with available demographic detail was used for valid and precise assessment of the pandemic situation. RESULTS: From 30 054 samples, the results were available for 29 891 samples and the crude seropositivity is 17.61%. For all the various age groups, the seropositivity calculated between 15% and 20%. The difference in seropositivity for both the sex group is statistically not significant. The seropositivity is significantly lower (13.64%) for HCWs as compared with non-HCWs (18.71%). Seropositivity shows increasing trend with time. Zone with maximum initial cases has high positivity as compared with other zones. UPHCs with recent rise in cases are leading in seropositivity as compared with earlier and widely affected UPHCs. CONCLUSIONS: The results of serosurveillance suggest that the population of Ahmedabad is still largely susceptible. People still need to follow preventive measures to protect themselves till an effective vaccine is available to the people at large. The data indicate the possibility of vanishing immunity over time and need further research to cross verify with scientific evidences.

LincRNA-immunity landscape analysis identifies EPIC1 as a regulator of tumor immune evasion and immunotherapy resistance.

Through an integrative analysis of the lincRNA expression and tumor immune response in 9,626 tumor samples across 32 cancer types, we developed a lincRNA-based immune response (LIMER) score that can predict the immune cells infiltration and patient prognosis in multiple cancer types. Our analysis also identified tumor-specific lincRNAs, including EPIC1, that potentially regulate tumor immune response in multiple cancer types. Immunocompetent mouse models and in vitro co-culture assays demonstrated that EPIC1 induces tumor immune evasion and resistance to immunotherapy by suppressing tumor cell antigen presentation. Mechanistically, lincRNA EPIC1 interacts with the histone methyltransferase EZH2, leading to the epigenetic silencing of IFNGR1, TAP1/2, ERAP1/2, and MHC-I genes. Genetic and pharmacological inhibition of EZH2 abolish EPIC1's immune-related oncogenic effect and its suppression of interferon-γ signaling. The EPIC1-EZH2 axis emerges as a potential mechanism for tumor immune evasion that can serve as therapeutic targets for immunotherapy.

Genetic inhibition of NFATC2 attenuates asparaginase hypersensitivity in mice.

The family of nuclear factor of activated T cells (NFAT) transcription factors plays a critical role in mediating immune responses. Our previous clinical pharmacogenetic studies suggested that NFATC2 is associated with the risk of hypersensitivity reactions to the chemotherapeutic agent L-asparaginase (ASNase) that worsen outcomes during the treatment of pediatric acute lymphoblastic leukemia. We therefore hypothesized that the genetic inhibition of NFATC2 would protect against the development of anti-ASNase antibodies and ASNase hypersensitivity. Our study demonstrates that ASNase-immunized NFATC2-deficient mice are protected against ASNase hypersensitivity and develop lower antigen-specific and total immunoglobulin E (IgE) levels compared with wild-type (WT) controls. Furthermore, ASNase-immunized NFATC2-deficient mice develop more CD4+ regulatory T cells, fewer CD4+ interleukin-4-positive (IL-4+) cells, higher IL-10/TGF-ß1 levels, and lower IL-4/IL-13 levels relative to WT mice. Basophils and peritoneal mast cells from ASNase-immunized, but not naïve, NFATC2-deficient mice had lower FcεRI expression and decreased IgE-mediated mast cell activation than WT mice. Furthermore, ASNase-immunized, but not naïve, NFATC2-deficient mice developed less severe shock than WT mice after induction of passive anaphylaxis or direct histamine administration. Thus, inhibition of NFATC2 protects against ASNase hypersensitivity by impairing T helper 2 responses, which may provide a novel strategy for attenuating hypersensitivity and the development of antidrug antibodies, including to ASNase.

Hospital based serological evidence of rickettsial diseases and assessment diagnostic tests of pyrexia of unknown origin.

The present study examined hospital-based serological tests of rickettsial infections and assessment for diagnosis of pyrexia of unknown origin (PUO). Blood samples were tested for Weil Felix antigens, ELISA for scrub typhus group and polymerase chain reaction (PCR) to detect the presence of DNA of spotted and scrub typhus group with the help of specific oligonucleotide. We tested 450 patient samples and found 101 Weil Felix-positive with 15 having ≥320 titres. IgM ELISA identified 32 (7.1%) positive cases. Positive PCR was seen in 13 (2.9%) samples, being only 40.1% of those testing positive for ELISA. Rickettsial infection is predominantly diagnosed through serological evidence in combination with molecular techniques. The Weil Felix test has a number of disadvantages and tends to provide false-positive results in a number of scenarios, especially where scrub typhus and spotted fever are widely distributed.

Antimicrobial resistance, mechanisms and its clinical significance.

Antimicrobial agents play a key role in controlling and curing infectious disease. Soon after the discovery of the first antibiotic, the challenge of antibiotic resistance commenced. Antimicrobial agents use different mechanisms against bacteria to prevent their pathogenesis and they can be classified as bactericidal or bacteriostatic. Antibiotics are one of the antimicrobial agents which has several classes, each with different targets. Consequently, bacteria are endlessly using methods to overcome the effectivity of the antibiotics by using distinct types of mechanisms. Comprehending the mechanisms of resistance is vital for better understanding and to continue use of current antibiotics. Which also helps to formulate synthetic antimicrobials to overcome the current mechanism of resistance. Also, encourage in prudent use and misuse of antimicrobial agents. Thus, decline in treatment costs and in the rate of morbidity and mortality. This review will be concentrating on the mechanism of actions of several antibiotics and how bacteria develop resistance to them, as well as the method of acquiring the resistance in several bacteria and how can a strain be resistant to several types of antibiotics. This review also analyzes the prevalence, major clinical implications, clinical causes of antibiotic resistance. Further, it evaluates the global burden of antimicrobial resistance, identifies various challenges and strategies in addressing the issue. Finally, put forward certain recommendations to prevent the spread and reduce the rate of resistance growth.

Creatine based polymer for codelivery of bioengineered MicroRNA and chemodrugs against breast cancer lung metastasis.

Metastasis is the major cause for breast cancer related mortality. The combination of miRNA-based therapy and chemotherapy represents a promising approach against breast cancer lung metastasis. The goal of this study is to develop an improved therapy that co-delivers a novel bioengineered miRNA prodrug (tRNA-mir-34a) and doxorubicin (DOX) via a multifunctional nanomicellar carrier that is based on a conjugate of amphiphilic copolymer POEG-VBC backbone with creatine, a naturally occurring cationic molecule. Co-delivery of DOX leads to more effective processing of tRNA-mir-34a into mature miR-34a and down-regulation of target genes. DOX + tRNA-mir-34a/POEG-PCre exhibits potent synergistic anti-tumor and anti-metastasis activity in vitro and in vivo. Interestingly, the enhanced immune response contributes to the overall antitumor efficacy. POEG-PCre may represent a safe and effective delivery system for an optimal chemo-gene combination therapy.

Doxorubicin delivered by a redox-responsive dasatinib-containing polymeric prodrug carrier for combination therapy.

Two novel prodrug polymers POEG-b-PSSDas (redox-sensitive) and POEG-b-PCCDas (redox-insensitive), which consist of poly(oligo(ethylene glycol) methacrylate) (POEG) hydrophilic blocks and dasatinib (DAS, an oncogenic tyrosine kinases inhibitor) conjugated hydrophobic blocks, were designed as dual-functional carriers for codelivery with doxorubicin (DOX). Both carriers retained antitumor activity of DAS and could form mixed micelles with DOX. Compared to POEG-b-PCCDas micelles, incorporation of disulfide linkage into POEG-b-PSSDas micelles facilitated efficient cleavage of DAS from prodrug micelles in tumor cells/tissues, leading to a higher level of anti-tumor activity in vitro and in vivo. In addition, DOX-loaded POEG-b-PSSDas micelles exhibited triggered DOX release under a redox environment (10mM glutathione, GSH), and demonstrated enhanced cytotoxicity against 4T1.2 and PC3 cell lines compared to DOX and DOX-loaded POEG-b-PCCDas micelles. More importantly, DOX-loaded POEG-b-PSSDas micelles were more effective in inhibiting the tumor growth and prolonging the survival rate in an aggressive murine breast cancer model (4T1.2) compared to DOX-loaded POEG-b-PCCDas micelles and a micellar formulation co-loaded with DOX and DAS. This redox-responsive prodrug micellar system provides an attractive strategy for effective combination of tumor targeted therapy and traditional chemotherapy, which warrants further investigation.

TGF-ß1 and contact mediated suppression by CD4+CD25+CD127- T regulatory cells of patients with self-limiting hepatitis E.

BACKGROUND AND AIM: Literature on the role of Regulatory T cells (Tregs) in acute viral infections is limited. Having established that the Tregs in self-limiting hepatitis E infection are elevated and functional, this study has focused on characterizing the specificity, phenotypes and identifying the molecules or factors responsible for enhancement of Treg cells and abrogation of Treg-mediated suppression in hepatitis E. METHODS: HEV rORF2p specific (a) Treg frequency, subset analysis and expression of surface and intracellular markers on Tregs and CFSE based functional analysis by flow cytometry (b) key cytokines quantification by multiplex (c) suppressive functional assay in the presence of anti-TGF-ß1 or anti-IL-10 or both antibodies or Transwell insert or in combination were performed on samples from 58 acute patients (AVH-E), 45 recovered individuals from hepatitis E and 55 controls. RESULTS: In AVH-E, the increased frequencies of Tregs and Teff cells were HEV rORF2p specific and Treg cells were of effector memory phenotype. Higher expressions of HEV rORF2p stimulated CTLA-4, GITR, PD1L, CD103, CD39, TLR2 and TGF-ß1 molecules on Tregs of AVH-E were observed. Tregs produced TGF-ß1 and inhibited the secretion of IFN-γ. Transwell insert and cytokines blocking assays indicated Tregs mediated suppression in AVH-E patients is majorly TGF-ß1 mediated and partly cell-cell contact mediated. CONCLUSION: Overall, we have identified beneficial involvement of HEV specific, functional Tregs and TGF-ß1 as the regulatory molecule responsible for enhancement of Tregs in self-limiting HEV infection. Therefore, use of TGF-ß1 as a possible supplement for boosting Treg response in recovery from severe hepatitis E needs evaluation.