Broadly Neutralizing Anti- HIV-1 Antibodies Do Not Inhibit HIV-1 Env-Mediated Cell-Cell Fusion

PG9, PG16, PGT121, and PGT145 antibodies were identified from culture media of activated memory B-cells of an infected donor and shown to neutralize many HIV-1 strains. Since HIV-1 spreads via both free virions and cell-cell fusion, we examined the effect of the antibodies on HIV-1 Env-mediated cell-cell fusion. Clone69TRevEnv cells that express Env in the absence of tetracycline were labeled with Calcein-AM Green, and incubated with CD4+ SupT1 cells labeled with CellTrace™ Calcein Red-Orange, with or without antibodies. Monoclonal antibodies PG9, PG16, 2G12, PGT121, and PGT145 (at up to 50 µg/mL) had little or no inhibitory effect on fusion between HIV-Env and SupT1 cells. By contrast, Hippeastrum hybrid agglutinin completely inhibited fusion. Our results indicate that transmission of the virus or viral genetic material would not be inhibited by these broadly neutralizing antibodies. Thus, antibodies generated by HIV-1 vaccines should be screened for their inhibitory effect on Env-mediated cell-cell fusion.

BROADLY NEUTRALIZING ANTI- HIV-1 ANTIBODIES DO NOT INHIBIT HIV-1 ENV-MEDIATED CELL-CELL FUSION

PG9, PG16, PGT121, and PGT145 antibodies were identified from culture media of activated memory B-cells of an infected donor and shown to neutralize many HIV-1 strains. Since HIV-1 spreads via both free virions and cell-cell fusion, we examined the effect of the antibodies on HIV-1 Env-mediated cell-cell fusion. Clone69TRevEnv cells that express Env in the absence of tetracycline were labeled with Calcein-AM Green, and incubated with CD4+ SupT1 cells labeled with CellTrace Calcein Red-Orange, with or without antibodies. Monoclonal antibodies PG9, PG16, 2G12, PGT121, and PGT145 (at up to 50 μg/mL) had little or no inhibitory effect on fusion between HIV-Env and SupT1 cells. By contrast, Hippeastrum hybrid agglutinin completely inhibited fusion. Our results indicate that transmission of the virus or viral genetic material would not be inhibited by these broadly neutralizing antibodies. Thus, antibodies generated by HIV-1 vaccines should be screened for their inhibitory effect on Env-mediated cell-cell fusion.

Neurological Diseases Associated to Immune Checkpoint Inhibitors

The treatment for cancer has been more widespread and new therapies appear as alternatives in the area to contain the advance of the tumor, having with the immune mechanisms one of the main sources of research and study for a possible advance in the treatment. Checkpoint inhibitors (ICI) are monoclonal therapy, which act by blocking the PD-1, PD-L1 and CTLA-4 molecules, responsible for immune control. However, among the effects caused by therapy, the use of medications is associated with neurological diseases reported as an adverse effect. Neurological complications can affect both the central and the peripheral nervous system, reaching a variety of regions and being related to effects in several diseases. In clinical practice, the report in question shows how the adverse effects of using these therapies work, collaborating with evidence on the use or not of it. This bibliographic review, which used the PUBMED database with the words "antibodies", "monoclonal", "immune control", "checkpoints inhibitors", brings the main neurological diseases associated with therapy, as well as the incidence, symptoms and treatment. Methodology: The present review used as a means of obtaining information the PUBMED platform, in which it was looking for articles using the words "" antibodies "," monoclonal "," immune control "," checkpoints inhibitors ", in addition to fulfilling the year criteria between 2010 and 2020. The language and countries in which the data were obtained were not selected, so information from articles published in several countries was used.

From Polyclonal Sera to Recombinant Antibodies: A Review of Immunological Detection of Gluten in Foodstuff

Gluten is the ethanol-soluble protein fraction of cereal endosperms like wheat, rye, and barley. It is widely used in the food industry because of the physical–chemical properties it gives to dough. Nevertheless, there are some gluten-related diseases that are presenting increasing prevalences, e.g., celiac disease, for which a strict gluten-free diet is the best treatment. Due to this situation, gluten labeling legislation has been developed in several countries around the world. This article reviews the gluten immune detection systems that have been applied to comply with such regulations. These systems have followed the development of antibody biotechnology, which comprise three major methodologies: polyclonal antibodies, monoclonal antibodies (mAbs) derived from hybridoma cells (some examples are 401.21, R5, G12, and α-20 antibodies), and the most recent methodology of recombinant antibodies. Initially, the main objective was the consecution of new high-affinity antibodies, resulting in low detection and quantification limits that are mainly achieved with the R5 mAb (the gold standard for gluten detection). Increasing knowledge about the causes of gluten-related diseases has increased the complexity of research in this field, with current efforts not only focusing on the development of more specific and sensitive systems for gluten but also the detection of protein motifs related to pathogenicity. New tools based on recombinant antibodies will provide adequate safety and traceability methodologies to meet the increasing market demand for gluten-free products.

A Simple and Efficient Genetic Immunization Protocol for the Production of Highly Specific Polyclonal and Monoclonal Antibodies against the Native Form of Mammalian Proteins

We have generated polyclonal and monoclonal antibodies by genetic immunization over the last two decades. In this paper, we present our most successful methodology acquired over these years and present the animals in which we obtained the highest rates of success. The technique presented is convenient, easy, affordable, and generates antibodies against mammalian proteins in their native form. This protocol requires neither expensive equipment, such as a gene gun, nor sophisticated techniques such as the conjugation of gold microspheres, electroporation, or surgery to inject in lymph nodes. The protocol presented uses simply the purified plasmid expressing the protein of interest under a strong promoter, which is injected at intramuscular and intradermal sites. This technique was tested in five species. Guinea pigs were the animals of choice for the production of polyclonal antibodies. Monoclonal antibodies could be generated in mice by giving, as a last injection, a suspension of transfected cells. The antibodies detected their antigens in their native forms. They were highly specific with very low non-specific background levels, as assessed by immune-blots, immunocytochemistry, immunohistochemistry and flow cytometry. We present herein a detailed and simple procedure to successfully raise specific antibodies against native proteins.

Epidemiology of infections caused by Chlamydophila pneumoniae in patients with chronic cough

Background: Chlamydophila pneumoniae is an important etiological agent in respiratory system infections. The aim of study was to analyze the rate of Chlamydophila pneumoniae infection in adults and children and also to determine a correlation between the presence of this pathogen and symptoms of chronic cough. Material/Methods: The material for the study included swabs from the posterior pharyngeal wall taken on an empty stomach without cleaning the mouth. The diagnostic method was indirect immunofluorescence test (IIFT), which uses two types of antibodies: monoclonal mouse antibodies, which link specifically with the antigen that is present in the tested material and goat anti-mouse antibodies linked to fluorescein isothiocyanate, providing the colour reaction with C. pneumoniae antigen. Results: In our research, 593 patients, including 319 women, 175 men, aged from 18 to 87 years and a group of 99 children aged from 2 to 17 years with symptoms of chronic cough n=432 and other respiratory manifestations n=161 were studied. In the group of studied women with cough, 28.2% (64/227) of results were positive. In the group of men with cough, 22.3% (27/121) of results were positive. In the group of children with a cough, 28.6% (24/84) of the results were positive. Conclusions: In the examined group of children and adults with a chronic cough, the C. pneumoniae antigen was detected. The frequency of detection of C. pneumoniae antigen differed depending on the age group of both children and adults with symptoms of chronic cough.

A Propósito do Artigo: “O Tratamento da Esclerose Múltipla com Natalizumab: Análise de uma Coorte Hospitalar”

Keywords: Multiple Sclerosis; Natalizumab; Treatment Outcome; Antibodies, Monoclonal, Humanized/ adverse effects; Leukoencephalopathy, Progressive Multifocal/chemically induced.

Q-fever presenting as an autoimmune disease: case report and review

Q fever is a worldwide zoonosis caused by the intracellular bacterium Coxiella burnetti. Autoimmune phenomena associated with the disease may obscure the clinical picture, and in many reports mislead physicians to an initial diagnosis of an autoimmune disease. We present a case of chronic Q-fever, complicated by myocarditis/pericarditis, where patient’s initial signs, symptoms and laboratory findings (i.e., protracted fever, oligoarthritis, erythema nodosum, positive antineutrophil cytoplasmic antibodies, monoclonal gammopathy) seemed to suggest an autoimmune disease. We also review the literature for autoimmune phenomena associated with Q-fever.