İnfection immunology

Background: Trichomonas vaginalis infection is the most prevalent non-viral sexually transmitted infection worldwide. Interactions between this infection and human immunodeficiency virus (HIV) may cause adverse pregnancy outcomes such as preterm labour, premature rupture of membranes, chorioamnionitis, low birth weight and post-abortal sepsis. Aims: This study was aimed to determine the prevalence and risk factors of T. vaginalis infection amongst HIV-positive pregnant women attending antenatal care at the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria...

This paper aimed to investigate the effect of Yinhua Pinggan granule and San-ao decoction on the immunologic mechanisms of influenza viral pneumonia mice in vivo , in order to study the activity of the combined administration of different formulas on influenza A/H1N1 virus. The model of pneumonia was established in mice through nasal dropping influenza virus, and then divided randomly into five groups: normal control group, influenza virus model group, oseltamivir control group, Yinhua Pinggan granule group, and San-ao decoction group...

Ascertaining the dominant cell type driving an immunological disease is essential to understanding the causal pathology and, therefore, selecting or developing an effective treatment. Classifying immunological diseases in this way has led to successful treatment regimens for many monogenic diseases; however, when the dominant cell type is unclear and there is no obvious causal genetic mutation, then identifying the correct disease classification and appropriate therapy can be challenging. In this review we focus on pulmonary immunological diseases where an innate immune signature has been identified as a predominant aspect of the immunopathology...

TaiMed Biologics is developing ibalizumab (Trogarzo™, ibalizumab-uiyk)-a humanised IgG4 monoclonal antibody-as a treatment for HIV-1 infection. Ibalizumab blocks HIV entry into CD4 cells while preserving normal immunological function and is the first CD4-directed post-attachment HIV-1 inhibitor and the first humanised monoclonal antibody for the treatment of HIV/AIDS. This article summarizes the milestones in the development of ibalizumab leading to this first approval in HIV-1 treatment.

The liver has been characterized as a frontline lymphoid organ with complex immunological features such as liver immunity and liver tolerance. Liver tolerance plays an important role in liver diseases including acute inflammation, chronic infection, autoimmune disease, and tumors. The liver contains a large proportion of natural killer (NK) cells, which exhibit heterogeneity in phenotypic and functional characteristics. NK cell activation, well known for its role in the immune surveillance against tumor and pathogen-infected cells, depends on the balance between numerous activating and inhibitory signals...

In the first half of the twentieth century, the Major Histocompatibility Complex (MHC) of the laboratory mouse, the H-2 complex, was defined by a combination of serology and genetics. In the second half of the twentieth century, its human counterpart, the Human Leukocyte Antigen (HLA) complex was similarly defined and shown to mediate rejection of allogeneic kidney grafts. The clinical relevance of the transplantation antigens created the field of transplant immunology, which aimed to reduce graft rejection by HLA matching of transplant donors and recipients, and to use immunosuppressive drugs to prevent and treat rejection...

Astragalus polysaccharides (APS), one of the major active components in Astragalus membranaceus, is an effective immunomodulator used in the treatment of immunological diseases in China. However, the anti-infective action and mechanism of APS is not fully known. In the present study, we found that APS induced the expression of human cathelicidin antimicrobial peptide LL-37, a key host anti-infective molecule, in both mRNA and protein levels in respiratory epithelial cells HBE16 and A549. Furthermore, the lysate and supernatant from APS-treated HBE16 cells both exhibited an obvious antibacterial action, which was partially neutralizated by LL-37 monoclonal antibody...

Hepatitis B (HepB) vaccination is the primary means of preventing infections and complications caused by hepatitis B virus (HBV). On February 21, 2018, the Advisory Committee on Immunization Practices (ACIP) recommended Heplisav-B (HepB-CpG), a yeast-derived vaccine prepared with a novel adjuvant, administered as a 2-dose series (0, 1 month) for use in persons aged ≥18 years. The ACIP Hepatitis Vaccines Work Group conducted a systematic review of the evidence, including data from four randomized controlled trials assessing prevention of HBV infection and six randomized controlled trials assessing adverse events in adults...

Dairy calf rearing unit is a management system that is only recently being implemented by some milk producer's cooperatives in southern Brazil. However, aspects related to the health profile of the heifer calves that arrive in the rearing unit as well as about biosecurity practices and microbiological challenges have not yet been evaluated in this rearing system in a tropical country. Diarrhea is the main and most frequent consequence of enteric infections in newborn calves. This study, through some etiological and epidemiological characteristics of an outbreak of neonatal diarrhea, has the aim to alert to the possibility of pathogenic microorganism spread in a dairy heifer calf rearing unit...

Cryptococcal meningoencephalitis is responsible for upwards of 15% of HIV-related deaths worldwide and is currently the most common cause of non-viral meningitis in the US, affecting both previously healthy and people with immune suppression caused by cancer chemotherapy, transplantation, and biologic therapies. Despite a continued 30-50% attributable mortality, recommended therapeutic strategies have remained largely unchanged since the 1950s. Recent murine models and human studies examining the role of the immune system in both susceptibility to the infection as well as host damage have begun to influence patient care decisions...

Immunodeficient mice transplanted with human cell populations or tissues, also known as human immune system (HIS) mice, have emerged as an important and versatile tool for the in vivo study of human immunodeficiency virus-type 1 (HIV-1) pathogenesis, treatment, and persistence in various biological compartments. Recent work in HIS mice has demonstrated their ability to recapitulate critical aspects of human immune responses to HIV-1 infection, and such studies have informed our knowledge of HIV-1 persistence and latency in the context of combination antiretroviral therapy...

People living with HIV can experience the full benefits of retention when they are continuously engaged in care. Continuous engagement in care promotes improved adherence to ART and positive health outcomes. An infectious disease clinic has implemented a protocol to primarily improve patient retention. The retrospective, facility-based, costing study took place in an infectious disease clinic in Washington DC. Retention was defined in two ways and over a 12-month period. Micro-costing direct measurement methods were used to collect unit costs in time series...

A human immunodeficiency virus type-1 (HIV-1) vaccine which is able to effectively prevent infection would be the most powerful method of extinguishing pandemic of the acquired immunodeficiency syndrome (AIDS). Yet, achieving such vaccine remains great challenges. The membrane-proximal external region (MPER) is a highly conserved region of the envelope glycoprotein (Env) gp41 subunit near the viral envelope surface, and it plays a key role in membrane fusion. It is also the target of some reported broadly neutralizing antibodies (bNAbs)...

IgG4-related disease is a fibroinflammatory systemic condition characterized by tumefactive lesions, lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells, storiform fibrosis, and elevated serum IgG4 concentrations. It has been described in virtually every organ system. Autoimmunity and infectious agents are potential immunologic triggers in IgG4-related disease. Herein, we describe a peculiar case of effusive-constrictive pericarditis in an 18-year-old boy with polyserositis and concomitant Necator americanus infection...

West Nile virus (WNV) is a positive-sense single-stranded RNA flavivirus belonging to the Japanese encephalitis virus (JEV) serocomplex of the Flaviviridae family and causes mosquito-borne infections. Although most human infection cases are asymptomatic, approximately one in 150 infected individuals develops meningoencephalitis, with a mortality rate of 4-14%. While the development of human neutralizing antibody therapeutics against WNV is strongly anticipated, WNV is difficult to study in conventional laboratories due to its high safety level requirement...

OBJECTIVE: Delineate risk factors associated with severe hypoxemia (O2 sat ≤87%) in infants and children younger than 2 years hospitalized with single pathogen HRV infection. STUDY DESIGN: Prospective study in a yearly catchment population of 56 560 children <2 years old between 2011 and 2013 in Argentina. All children with respiratory signs and O2 sat <93% on admission were included. HRV infections were identified by reverse transcriptase-polymerase chain reaction...

Over the last decades, there was increasing evidence for the presence of innate immune memory in living organisms. In this review, we compare the innate immune memory of various organisms with a focus on phylogenetics. We discuss the acquisition and molecular basis of immune memory and we describe the innate immune memory paradigm and its role in host defense during evolution. The molecular characterization of innate immunological memory in diverse organisms and host-parasite systems reconciles mechanisms with phenomena and paves the way to molecular comprehension of innate immune memory...

During infections and cancer, the composition of the T-cell receptor (TCR) repertoire of antigen-specific CD8+ T cells changes over time. TCR avidity is thought to be a major driver of this process, thereby interacting with several additional regulators of T-cell responses to form a composite immune response architecture. Infections with latent viruses, such as cytomegalovirus (CMV), can lead to large T-cell responses characterized by an oligoclonal TCR repertoire. Here, we review the current status of experimental studies and theoretical models of TCR repertoire evolution during CMV infection...

Vaccines or early childhood exposure to infection mediate immunity, that is, improved resistance against disease and death caused by a second infection with the same agent. This has been explained by and equaled to immunological memory, that is, an "altered immune system behavior" that is maintained in a presumably antigen-independent fashion. This review summarizes epidemiological and experimental data, that largely falsify this idea and that show that periodic re-exposure to antigen either, artificially as vaccines or naturally as low-level persisting antigens or infections, or immune complexes on follicular dendritic cells or endemic re-exposure is necessary for protection...

The generation of memory B cells (MBCs) that have undergone immunoglobulin class switching from IgM, which dominates primary antibody responses, to other immunoglobulin isoforms is a hallmark of immune memory. Hence, humoral immunological memory is characterized by the presence of serum immunoglobulins of IgG subtypes known as the γ-globulin fraction of blood plasma proteins. These antibodies reflect the antigen experience of B lymphocytes and their repeated triggering. In fact, efficient protection against a previously encountered pathogen is critically linked to the production of pathogen-specific IgG molecules even in those cases where the primary immune response required cellular immunity, for example, T cell-mediated clearance of intracellular pathogens such as viruses...