İnfection immunology

BACKGROUND: PGF is historically associated with high morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: In this study, we report our multicenter experience on stem cell boost (SCB) for PGF, or incomplete donor engraftment, in 16 pediatric patients. Donors were HLA-matched siblings (n = 4), unrelated donors (n = 11), or haploidentical family members (n = 1). Ten patients had two-lineage cytopenia, 5 had one-lineage cytopenia, and 1 had poor immunological reconstitution together with a low percentage of donor cell engraftment...

In December 2019, a new species of pneumonia-causing betacoronavirus was identified in Wuhan, China, which was later identified as SARS-CoV-2. This RNA virus presents certain similarities with other viruses of the same genetic material. It has been seen that infection by human immunodeficiency virus resembles the infection by SARS-CoV-2 in various aspects. In this comment, we present some of the virological, immunological, clinical, and pharmacological similarities between HIV and SARS-CoV-2, which could allow us to understand the immunopathogenesis of COVID-19 better, as well as make some decisions in regarding antiviral management...

Antibody-mediated rejection (AMR) that resists to standard of care (SOC) therapy remains a major challenge after kidney transplantation and leads to graft failure in a majority of cases. The use of anti-IL6 receptor antibodies was suggested to treat chronic antibody-mediated rejection (cAMR) after failure of classical treatments. We treated nine patients with AMR resistant to apheresis, rituximab, and intravenous immunoglobulins, with a monthly infusion of tocilizumab and compared them with a historical cohort of 37 patients with similar clinical, immunological, and histological characteristics...

In the last 20 years, the global regulatory frameworks for drug assessment have been managing the challenges posed by using cellular products as new therapeutic tools. Currently, they are defined as "Advanced Therapy Medicinal Products", comprising a large group of cellular types that either alone or in combination with gene and tissue engineering technology. They have the potential to change the natural course of still lethal or highly debilitating diseases, including cancers, opportunistic infections and chronic inflammatory conditions...

Platelets have a predominant role in haemostasis, the maintenance of blood volume and emerging roles as innate immune cells, in wound healing and in inflammatory responses. Platelets express receptors that are important for platelet adhesion, aggregation, participation in inflammatory responses, and for triggering degranulation and enhancing thrombin generation. They carry a cargo of granules bearing enzymes, adhesion molecules, growth factors and cytokines, and have the ability to generate reactive oxygen species...

Recent studies have provided insights into the pathology and immune response to coronavirus disease 2019 (COVID-19) 1-8 . However thorough interrogation of the interplay between infected cells and the immune system at sites of infection is lacking. We use high parameter imaging mass cytometry 9 targeting the expression of 36 proteins, to investigate at single cell resolution, the cellular composition and spatial architecture of human acute lung injury including SARS-CoV-2. This spatially resolved, single-cell data unravels the disordered structure of the infected and injured lung alongside the distribution of extensive immune infiltration...

OBJECTIVES: To evaluate belimumab effectiveness and safety in real-life Portuguese patients with Systemic Lupus Erythematosus (SLE). MATERIALS AND METHODS: Multicenter cohort study including all SLE patients treated with belimumab in seven Portuguese rheumatology centers. Demographic, clinical and serological data were collected at baseline, 6, 12 and 24 months of treatment with belimumab. To evaluate effectiveness we used SLE Responder Index (SRI) rates and changes in SELENA-SLEDAI...

During infection with the human immunodeficiency virus type 1 (HIV-1), latent reservoirs are established, which circumvent full eradication of the virus by antiretroviral therapy (ART) and are the source for viral rebound after cessation of therapy. As these reservoirs are phenotypically indistinguishable from infected cells, current strategies aim to reactivate these reservoirs, followed by pharmaceutical and immunological destruction of the cells.Here, we employed a simple and convenient cell-based reporter system, which enables sample handling under biosafety level (BSL)-1 conditions, to screen for compounds that were able to reactivate latent HIV-1...

Pregnant women experience physiological and immunological changes which make them more prone to all kind of viral and bacterial infections, this is because they have been considered as vulnerable group if infected by SARS-CoV-2. They could even deploy a severe form of this disease which may require to end pregnancy to improve oxygenation and to safeguard foetal wellbeing the in case the mother situation gets worse. In this scenario, any intervention would require a detailed planning by the whole surgical team, and, specifically, by the anaesthesiologists, in order to guarantee both mother and child wellbeing and to prevent from infections all the healthcare team...

The application of next-generation molecular, biochemical and immunological methods for developing new vaccines, antimicrobial compounds, probiotics and prebiotics for zoonotic infection control has been fundamental to the understanding and preservation of the symbiotic relationship between animals and humans. With increasing rates of antibiotic use, resistant bacterial infections have become more difficult to diagnose, treat, and eradicate, thereby elevating the importance of surveillance and prevention programs...

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic was first reported in Wuhan, China in December 2019, moved across the globe at an unprecedented speed, and is having a profound and yet still unfolding health and socioeconomic impacts. SARS-CoV-2, a β-coronavirus, is a highly contagious respiratory pathogen that causes a disease that has been termed the 2019 coronavirus disease (COVID-19). Clinical experience thus far indicates that COVID-19 is highly heterogeneous, ranging from being asymptomatic and mild to severe and causing death...

Vaccines against infectious diseases have had great successes in the history of public health. Major breakthroughs have occurred in the development of vaccine-based interventions against viral and bacterial pathogens through the application of classical vaccine design strategies. In contrast the development of a malaria vaccine has been slow. Plasmodium falciparum malaria affects millions of people with nearly half of the world population at risk of infection. Decades of dedicated research has taught us that developing an effective vaccine will be time consuming, challenging, and expensive...

Influenza virus infection is a global public health threat. Current seasonal influenza vaccines are efficacious only when vaccine strains are matched with circulating strains. There is a critical need for developing "universal" vaccines that protect against all influenza viruses. HA stem is a promising target for developing broad-spectrum influenza vaccines due to its relatively conserved feature. However, HA stem is weakly immunogenic when administered alone in a soluble form. Several approaches have been employed to improve the immunogenicity of HA stem, including conjugation of HA stem with a highly immunogenic carrier protein or displaying HA stem on a nanoparticle scaffold...

Emerging and re-emerging viral diseases poses a threat to living organisms, and led to serious concern to humankind and public health. The last two decades, viral epidemics such as the severe acute respiratory syndrome (SARS-CoV) reported in the years 2002-2003, and H1N1 influenza (Swine flu) in 2009, middle east respiratory syndrome (MERS-CoV) from Saudi Arabia in 2012, Ebola virus in 2014-2016, and Zika virus in 2015. The recent outbreak of 2019-CoV-2 or severe acute respiratory syndrome-2 (SARS-CoV-2), novel coronavirus (2019-nCoV, or 2019 disease, COVID-19) in Dec 2019, from, Wuhan city of China, has severe implications of health concerns to the whole world, due to global spread and high health risk...

Older kidney transplant recipients demonstrate increased rates of infection but decreased rates of rejection compared with younger recipients, suggesting that older transplant patients are functionally overimmunosuppressed. We hypothesized that this is a consequence of reduction in immunological activity due to biological aging and that an immune biological age, as determined by DNA methylation (DNAm), would be associated more strongly with incidence of infection than chronological age. Methods: DNAm analysis was performed on peripheral blood mononuclear cell collected from 60 kidney transplant recipients representing older (≥age 60 y) and younger (aged 30-59 y) patients 3 months after transplantation...

Background: Despite the pandemic, data are limited regarding COVID-19 infection in pregnant women and newborns. This report aimed to bring new information about presentation that could modify precautionary measures for infants born of mothers with a remote history of COVID-19. Methods: We report two infants with possible maternofetal transmission, and four mothers without immunologic reactions. Data were collected from the patient files. Results: One mother exhibited infection signs 10 days before uncomplicated delivery, with negative RT-PCR and no antibody detection thereafter...

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening rare disease resulting from the uncontrolled activation of the immune system, leading to unrestrained cytokine release and macrophage activation. It can be either hereditary or acquired due to infections, hematological disease or malignancy. CASE REPORT: We present the case of a 19-year old woman that presented with high fever and acute cholestatic hepatitis. She was initially admitted to the Gastroenterology department and the following days she developed respiratory distress and multiorgan insufficiency that necessitated intubation and support in the Intensive Care Unit...

Parasitic helminths infect over one-fourth of the human population resulting in significant morbidity, and in some cases, death in endemic countries. Despite mass drug administration (MDA) to school-aged children and other control measures, helminth infections are spreading into new areas. Thus, there is a strong rationale for developing anthelminthic vaccines as cost-effective, long-term immunological control strategies, which, unlike MDA, are not haunted by the threat of emerging drug-resistant helminths nor limited by reinfection risk...

The risk and severity of specific infections are increased during pregnancy due to a combination of physiological and immunological changes. Characterizing the maternal immune system during pregnancy is important to understand how the maternal immune system maintains tolerance towards the allogeneic fetus. This may also inform strategies to prevent maternal fatalities due to infections and optimize maternal vaccination to best protect the mother-fetus dyad and the infant after birth. In this review, we describe what is known about the immunological changes that occur during a normal pregnancy...

Epitopes, in the context of T cell recognition, are short peptides typically derived by antigen processing, and presented on the cell surface bound to MHC molecules (HLA molecules in humans) for TCR scrutiny. The identification of epitopes is a context-dependent process, with consideration given to, for example, the source pathogen and protein, the host organism, and state of the immune reaction (e.g., following natural infection, vaccination, etc.). In the following review, we consider the various approaches used to define T cell epitopes, including both bioinformatic and experimental approaches, and discuss the concepts of immunodominance and immunoprevalence...