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Author(s):  
Ritopa Das ◽  
Sofia Langou ◽  
Thinh T. Le ◽  
Pooja Prasad ◽  
Feng Lin ◽  
...  

Immunotherapy is becoming a very common treatment for cancer, using approaches like checkpoint inhibition, T cell transfer therapy, monoclonal antibodies and cancer vaccination. However, these approaches involve high doses of immune therapeutics with problematic side effects. A promising approach to reducing the dose of immunotherapeutic agents given to a cancer patient is to combine it with electrical stimulation, which can act in two ways; it can either modulate the immune system to produce the immune cytokines and agents in the patient’s body or it can increase the cellular uptake of these immune agents via electroporation. Electrical stimulation in form of direct current has been shown to reduce tumor sizes in immune-competent mice while having no effect on tumor sizes in immune-deficient mice. Several studies have used nano-pulsed electrical stimulations to activate the immune system and drive it against tumor cells. This approach has been utilized for different types of cancers, like fibrosarcoma, hepatocellular carcinoma, human papillomavirus etc. Another common approach is to combine electrochemotherapy with immune modulation, either by inducing immunogenic cell death or injecting immunostimulants that increase the effectiveness of the treatments. Several therapies utilize electroporation to deliver immunostimulants (like genes encoded with cytokine producing sequences, cancer specific antigens or fragments of anti-tumor toxins) more effectively. Lastly, electrical stimulation of the vagus nerve can trigger production and activation of anti-tumor immune cells and immune reactions. Hence, the use of electrical stimulation to modulate the immune system in different ways can be a promising approach to treat cancer.


Author(s):  
Nida Siddiqui ◽  
Brett Stephen Mansfield ◽  
Nine-Paula Olmesdahl ◽  
Peter Swart ◽  
Jeremy Nel

Paradoxical immune reconstitution inflammatory syndrome (IRIS) in human immunodeficiency virus (HIV)-positive patients initiating antiretroviral treatment (ART) is caused by restored immunity to specific antigens, resulting in worsening of a pre-existing infection. Molluscum contagiosum (MC) is commonly noted in HIV-positive individuals but ART alone is usually sufficient to bring about resolution. We present a rare case of severe MC-IRIS that worsened despite immune reconstitution.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Roberto Damián Moyano ◽  
Magali Andrea Romero ◽  
María Alejandra Colombatti Olivieri ◽  
María Fiorella Alvarado Pinedo ◽  
Gabriel Eduardo Traveria ◽  
...  

Bovine paratuberculosis (PTB) is caused by Mycobacterium avium subsp. paratuberculosis (MAP). The optimization of detection tests specific for MAP is crucial to improve PTB control. In this work, we aimed to develop and validate a diagnostic tool based on an ELISA to specifically detect anti-MAP antibodies from bovine serum samples. For that purpose, we designed a recombinant polyprotein containing four specific antigens from MAP and optimized the ELISA. The validation consisted of the assessment of 10 sera from PTB-infected and healthy bovines with different OD values. The diagnostic performance of the polyprotein-ELISA was evaluated by testing 130 bovine serum samples (47 healthy, 48 MAP-infected, and 35 M. bovis-infected bovines). The ELISA using the polyprotein yielded an area under the ROC curve (AUC) of 0.9912 (95% CI, 0.9758–1.007; P  < 0.0001). Moreover, for this ELISA, the cut-off selected from the ROC curve based on the point with a sensitivity of 95.56% (95% CI, 0.8485–0.9946) and specificity of 97.92 (95% CI, 0.8893–0.9995) was 0.3328. Similar results were obtained with an ELISA using the commercial Paratuberculosis Protoplasmatic Antigen (PPA). However, the ELISA with the polyprotein antigen showed a better performance against sera from animals infected with Mycobacterium bovis compared to the ELISA with PPA: lower cross-reactivity (2.85% versus 25.71%). These results demonstrate a very low cross-reactivity of the polyprotein with antibodies present in serum samples from animals infected with M. bovis. The designed polyprotein and the validated ELISA could be very useful for the specific identification of MAP-infected animals in herds.


2021 ◽  
Vol 59 (6) ◽  
pp. 615-623
Author(s):  
Yan Lu ◽  
Jia-Hui Sun ◽  
Li-Li Lu ◽  
Jia-Xu Chen ◽  
Peng Song ◽  
...  

Human sparganosis is a food-borne parasitic disease caused by the plerocercoids of Spirometra species. Clinical diagnosis of sparganosis is crucial for effective treatment, thus it is important to identify sensitive and specific antigens of plerocercoids. The aim of the current study was to identify and characterize the immunogenic proteins of Spirometra erinaceieuropaei plerocercoids that were recognized by patient sera. Crude soluble extract of the plerocercoids were separated using 2-dimensional gel electrophoresis coupled with immunoblot and mass spectrometry analysis. Based on immunoblotting patterns and mass spectrometry results, 8 antigenic proteins were identified from the plerocercoid. Among the proteins, cysteine protease protein might be developed as an antigen for diagnosis of sparganosis.


2021 ◽  
Author(s):  
Manon Janet-Maitre ◽  
Stephane Pont ◽  
Frerich Masson ◽  
Julian Trouillon ◽  
Mylene Robert-Genthon ◽  
...  

Persistence of bacterial pathogens is a main cause of treatment failure and establishment of chronic bacterial infection. Pseudomonas aeruginosa, an opportunistic Gram-negative pathogen is a leading cause of bacteremia with high associated mortality. In a previous study, we found that plasma-sensitive P. aeruginosa strains were able to form a persister-like sub-population named evaders. However, the molecular mechanisms underlying emergence and biology of evaders remained unknown. Here, using a gain-of-function genetic screen we examined the molecular determinants of persistence in plasma. In addition to known virulence factors (long O-specific antigens and exopolysaccharides), we found that ATP and biotin availability greatly impact bacterial survival in plasma. Mutants in genes of purine and biotin pathways display higher tolerance and persistence, respectively. Moreover, we identified a novel small protein named SrgA whose expression leads to 100-fold increase in survival in plasma. The analysis of different steps of complement activity and the use of outer-membrane impermeable drug nisin suggest that the mutants impede MAC activity per se. Through this work we highlight the multifactorial origin of bacterial resilience to plasma and pave the way to a more comprehensive picture of the complex interplay between P. aeruginosa and the complement system in the blood.


Author(s):  
Dr. Moumita Hazra

The basic oncotherapeutic vaccines used are cell based vaccines including whole cell vaccines, genetically modified tumour cell vaccines and dendritic cell vaccines, anti-idiotype antibody based vaccines, protein or peptide based vaccines, heat shock proteinbased vaccines, viral, bacterial or yeast vectors based vaccines, mRNA or DNA nucleic acid based vaccines, vaccines based on tumour associated antigens like overexpressed proteins, differentiation antigens, cancer-testis antigens and oncofoetal antigens, and tumour specific antigens including oncogenic viral antigens, antigen presenting cells or molecular neoantigens based vaccines with specific CD8+ T cells and, CD4+ T cells, and nanoparticles vectors based vaccines. The objective of this evidence-based medical research was the comparative quantification of TGF? and telomerase experimentations, with their molecular pharmacological analyses as targets of oncoimmunotherapeutic vaccines. A molecular pharmacological multi-variate, qualitative, analytical study of the retrieved literature derived through a thorough literature review from various available literature databases, was performed, to record, review, thoroughly analyse and delineate the molecular pharmacological basis of oncoimmunotherapeutic vaccines from a wide-ranged study literature containing molecular pharmacological researches, reviews, case presentations and varied databases about the pharmacooncoimmunotherapeutic rationale of the clinical use of vaccines in the treatment of cancer patients, with a specific emphasis on telomerase and TGF?, as molecular pharmacological targets of oncoimmunotherapeutic vaccines. After that, a multivariate evidence-based medical research study of comparative quantification and analysis of the global heterogenous multidisciplinary experimentations and study literature on telomerase and TGF?, as molecular pharmacological targets of pharmaco-oncoimmuno-therapeutic vaccines, affecting global malignant and borderline malign


2021 ◽  
Vol 12 ◽  
Author(s):  
Zachary Lamplugh ◽  
Yi Fan

Immunotherapy holds great promise for treating cancer. Nonetheless, T cell-based immunotherapy of solid tumors has remained challenging, largely due to the lack of universal tumor-specific antigens and an immunosuppressive tumor microenvironment (TME) that inhibits lymphocyte infiltration and activation. Aberrant vascularity characterizes malignant solid tumors, which fuels the formation of an immune-hostile microenvironment and induces tumor resistance to immunotherapy, emerging as a crucial target for adjuvant treatment in cancer immunotherapy. In this review, we discuss the molecular and cellular basis of vascular microenvironment-mediated tumor evasion of immune responses and resistance to immunotherapy, with a focus on vessel abnormality, dysfunctional adhesion, immunosuppressive niche, and microenvironmental stress in tumor vasculature. We provide an overview of opportunities and challenges related to these mechanisms. We also propose genetic programming of tumor endothelial cells as an alternative approach to recondition the vascular microenvironment and to overcome tumor resistance to immunotherapy.


Author(s):  
James Elliff

Theglobal health crisis caused by COVID-19 has overwhelmed both healthcaresettings and economies globally. Whilst mass population testing has improveddrastically, recent reviews of existing methods have highlighted variousshortcomings with these methods. Theaim of this project was to investigate whether the LAA could be modified andutilised as rapid detection test which either matched or exceeded the existingsensitivity and specificity values.&nbsp;&nbsp; TheLAA investigated whether the COVID-19 spike protein could be detected insamples. COVID-19 specific IgM and IgG were used in conjunction with a seriesof non-specific antigens. Control or AG containing samples weremixed with AB-microsphere complexes on glass microscope slides. Manualvisualisation identified various levels of agglutination. Light microscopy andspectrophotometry at 405nm determined that the LAA could detect at least 2.3ngof spike protein.&nbsp; Theparticle counting tool of ImageJ was utilised to obtain a dataset which wassubjected to statistical analysis which indicated that there was a significantdifference between control samples and live tests, P = 0.000102 for the spikeprotein assay and P = 0.254 for the non-specific assay respectively. Theresults obtained fell in line with a similar study conducted by Buffin et al in2018. Theanalytical methods used in this project twinned with data obtained in previousstudies supports the significant difference between control values and livetest values. The LAA is easier, quicker to use (results in ≤ 30 minutes) andcheaper, with potentially better sensitivity to existing methods. This couldbenefit high and low-income countries alike upon further research andoptimisation.&nbsp;


Author(s):  
Caitlin R Hopkins ◽  
Joseph A Fraietta

Chimeric antigen receptor (CAR) T cells have emerged as an effective therapy for patients with relapsed and refractory haematological malignancies. However, there are many challenges preventing clinical efficacy and thus broader translation of this approach. These hurdles include poor autologous T cell fitness, manufacturing issues and lack of conserved tumour-restricted antigens to target. Recent efforts have been directed toward incorporating genome editing technologies to address these challenges and develop potent CAR T cell therapies for a diverse array of haematopoietic cancers. In this review, the authors discuss gene editing strategies that have been employed to augment CAR T cell fitness, generate allogeneic ‘off-the-shelf’ CAR T cell products, and safely target elusive myeloid and T cell cancers that often lack appropriate tumour-specific antigens.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260496
Author(s):  
Siravit Sitprija ◽  
Lawan Chanhome ◽  
Onrapak Reamtong ◽  
Tipparat Thiangtrongjit ◽  
Taksa Vasaruchapong ◽  
...  

The venomic profile of Asian mountain pit viper Ovophis monticola is clarified in the present study. Using mass spectrometry-based proteomics, 247 different proteins were identified in crude venom of O. monticola found in Thailand. The most abundant proteins were snake venom metalloproteases (SVMP) (36.8%), snake venom serine proteases (SVSP) (31.1%), and phospholipases A2 (PLA2) (12.1%). Less abundant proteins included L-amino acid oxidase (LAAO) (5.7%), venom nerve growth factor (3.6%), nucleic acid degrading enzymes (3.2%), C-type lectins (CTL) (1.6%), cysteine-rich secretory proteins (CRISP) (1.2%) and disintegrin (1.2%). The immunoreactivity of this viper’s venom to a monovalent antivenom against green pit viper Trimeresurus albolabris, or to a polyvalent antivenom against hemotoxic venom was investigated by indirect ELISA and two-dimensional (2D) immunoblotting. Polyvalent antivenom showed substantially greater reactivity levels than monovalent antivenom. A titer for the monovalent antivenom was over 1:1.28x107 dilution while that of polyvalent antivenom was 1:5.12x107. Of a total of 89 spots comprising 173 proteins, 40 spots of predominantly SVMP, SVSP and PLA2 were specific antigens for antivenoms. The 49 unrecognized spots containing 72 proteins were characterized as non-reactive proteins, and included certain types of CTLs and CRISPs. These neglected venom constituents could limit the effectiveness of antivenom-based therapy currently available for victims of pit viper envenomation.


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