Publications by authors named "Breemen M"

HIV-1 infection leads to chronic disease requiring life-long treatment and therefore alternative therapeutics, a cure and/or a protective vaccine are needed. Antibody-mediated effector functions could have a role in the fight against HIV-1. However, the properties underlying the potential beneficial effects of antibodies during HIV-1 infection are poorly understood.

View Article and Find Full Text PDF

An effective human immunodeficiency virus 1 (HIV-1) vaccine will most likely have to elicit broadly neutralizing antibodies (bNAbs) to overcome the sequence diversity of the envelope glycoprotein (Env). So far, stabilized versions of Env, such as SOSIP trimers, have been able to induce neutralizing antibody (NAb) responses, but those responses are mainly strain-specific. Here we attempted to broaden NAb responses by using a multivalent vaccine and applying a number of design improvements.

View Article and Find Full Text PDF

Chemical cross-linking is used to stabilize protein structures with additional benefits of pathogen and toxin inactivation for vaccine use, but its use has been restricted by the potential for local or global structural distortion. This is of particular importance when the protein in question requires a high degree of structural conservation for inducing a biological outcome such as the elicitation of antibodies to conformationally sensitive epitopes. The HIV-1 envelope glycoprotein (Env) trimer is metastable and shifts between different conformational states, complicating its use as a vaccine antigen.

View Article and Find Full Text PDF

Targeting germline (gl-) precursors of broadly neutralizing antibodies (bNAbs) is acknowledged as an important strategy for HIV-1 vaccines. The VRC01-class of bNAbs is attractive because of its distinct genetic signature. However, VRC01-class bNAbs often require extensive somatic hypermutation, including rare insertions and deletions.

View Article and Find Full Text PDF

Effective treatments against Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) are urgently needed. Monoclonal antibodies have shown promising results in patients. Here, we evaluate the in vivo prophylactic and therapeutic effect of COVA1-18, a neutralizing antibody highly potent against the B.

View Article and Find Full Text PDF

One year into the Coronavirus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), effective treatments are still needed . Monoclonal antibodies, given alone or as part of a therapeutic cocktail, have shown promising results in patients, raising the hope that they could play an important role in preventing clinical deterioration in severely ill or in exposed, high risk individuals . Here, we evaluated the prophylactic and therapeutic effect of COVA1-18 , a neutralizing antibody isolated from a convalescent patient and highly potent against the B.

View Article and Find Full Text PDF

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is continuing to disrupt personal lives, global healthcare systems, and economies. Hence, there is an urgent need for a vaccine that prevents viral infection, transmission, and disease. Here, we present a two-component protein-based nanoparticle vaccine that displays multiple copies of the SARS-CoV-2 spike protein.

View Article and Find Full Text PDF

The induction of broad and potent immunity by vaccines is the key focus of research efforts aimed at protecting against HIV-1 infection. Soluble native-like HIV-1 envelope glycoproteins have shown promise as vaccine candidates as they can induce potent autologous neutralizing responses in rabbits and non-human primates. In this study, monoclonal antibodies were isolated and characterized from rhesus macaques immunized with the BG505 SOSIP.

View Article and Find Full Text PDF

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a large impact on global health, travel, and economy. Therefore, preventative and therapeutic measures are urgently needed. Here, we isolated monoclonal antibodies from three convalescent coronavirus disease 2019 (COVID-19) patients using a SARS-CoV-2 stabilized prefusion spike protein.

View Article and Find Full Text PDF
Article Synopsis
  • Stabilized HIV-1 envelope glycoproteins (Env) resembling the native form are being developed for vaccines to induce broadly neutralizing antibodies (bNAbs).
  • A new SOSIP trimer was created using a consensus sequence of all HIV-1 group M isolates, showcasing most known bNAb epitopes and some germline precursor ones.
  • The ConM trimer has shown to provoke strong neutralizing antibody (NAb) responses in animals, especially when delivered using ferritin nanoparticles, suggesting that consensus-based immunogens could aid in designing effective HIV-1 vaccines.
View Article and Find Full Text PDF

Immunoglobulin G (IgG) can contain -linked glycans in the variable domains, the so-called Fab glycans, in addition to the Fc glycans in the C2 domains. These Fab glycans are acquired following introduction of -glycosylation sites during somatic hypermutation and contribute to antibody diversification. We investigated whether Fab glycans may-in addition to affecting antigen binding-contribute to antibody stability.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on inducing broadly neutralizing antibodies (bNAbs) against HIV-1 using modified glycoproteins to activate naive B cells with germline antibody precursors.
  • Researchers reengineered the BG505 SOSIP.664 glycoprotein to better engage these germline precursors, successfully binding them in lab tests and activating B cells in mice.
  • The crystal structure of the modified trimer shows a native-like conformation, confirming its ability to engage multiple germline bNAb precursors effectively.
View Article and Find Full Text PDF

In June 2013, the first case of human infection with an avian H6N1 virus was reported in a Taiwanese woman. Although this was a single non-fatal case, the virus continues to circulate in Taiwanese poultry. As with any emerging avian virus that infects humans, there is concern that acquisition of human-type receptor specificity could enable transmission in the human population.

View Article and Find Full Text PDF

The avian H7N9 influenza outbreak in 2013 resulted from an unprecedented incidence of influenza transmission to humans from infected poultry. The majority of human H7N9 isolates contained a hemagglutinin (HA) mutation (Q226L) that has previously been associated with a switch in receptor specificity from avian-type (NeuAcα2-3Gal) to human-type (NeuAcα2-6Gal), as documented for the avian progenitors of the 1957 (H2N2) and 1968 (H3N2) human influenza pandemic viruses. While this raised concern that the H7N9 virus was adapting to humans, the mutation was not sufficient to switch the receptor specificity of H7N9, and has not resulted in sustained transmission in humans.

View Article and Find Full Text PDF

A challenge for HIV-1 immunogen design is the difficulty of inducing neutralizing antibodies (NAbs) against neutralization-resistant (tier 2) viruses that dominate human transmissions. We show that a soluble recombinant HIV-1 envelope glycoprotein trimer that adopts a native conformation, BG505 SOSIP.664, induced NAbs potently against the sequence-matched tier 2 virus in rabbits and similar but weaker responses in macaques.

View Article and Find Full Text PDF

Background: To examine the efficacy of valproic acid (VPA) given either with or without levetiracetam (LEV) on seizure control and on survival in patients with glioblastoma multiforme (GBM) treated with chemoradiation.

Methods: A retrospective analysis was performed on 291 patients with GBM. The efficacies of VPA and LEV alone and as polytherapy were analyzed in 181 (62%) patients with seizures with a minimum follow-up of 6 months.

View Article and Find Full Text PDF

Background: In children, neuroborreliosis often manifests itself as cranial neuritis (particularly facial palsy) or aseptic meningitis. Presentation with torticollis and simple partial seizures resulting from diffuse leptomeningeal inflammation is rare.

Case Description: A seven-year-old boy who had developed torticollis and partial seizures, lost weight and was complaining of tiredness was seen by a paediatric neurologist.

View Article and Find Full Text PDF

Gaucher disease, caused by a deficiency of the lysosomal enzyme glucocerebrosidase, leads to prominent glucosylceramide accumulation in lysosomes of tissue macrophages (Gaucher cells). Here we show glucosylsphingosine, the deacylated form of glucosylceramide, to be markedly increased in plasma of symptomatic nonneuronopathic (type 1) Gaucher patients (n = 64, median = 230.7 nM, range 15.

View Article and Find Full Text PDF

A biomarker is an analyte indicating the presence of a biological process linked to the clinical manifestations and outcome of a particular disease. In the case of lysosomal storage disorders (LSDs), primary and secondary accumulating metabolites or proteins specifically secreted by storage cells are good candidates for biomarkers. Clinical applications of biomarkers are found in improved diagnosis, monitoring disease progression, and assessing therapeutic correction.

View Article and Find Full Text PDF

Fabry disease is treated by two-weekly infusions with α-galactosidase A, which is deficient in this X-linked globotriaosylceramide (Gb3) storage disorder. Elevated plasma globotriaosylsphingosine (lysoGb3) is a hallmark of classical Fabry disease. We investigated effects of enzyme replacement therapy (ERT) on plasma levels of lysoGb3 and Gb3 in patients with classical Fabry disease treated with agalsidase alfa at 0.

View Article and Find Full Text PDF

The aim of this study was to compare plasma and serum protein profiles in elderly acute hip fracture patients with and without delirium. The spectra from surface-enhanced laser desorption ionization (SELDI) using time-of-flight (TOF) mass spectrometry of 16 patients without and 16 patients with delirium (two groups of eight and eight) scored using the Confusion Assessment Method were compared. The most discriminating peak of 15.

View Article and Find Full Text PDF

Gaucher disease is an inherited lysosomal storage disorder, characterized by massive accumulation of glucosylceramide-laden macrophages in the spleen, liver and bone marrow as a consequence of deficient activity of glucocerebrosidase. Gaucher disease has been the playground to develop new therapeutic interventions such as enzyme-replacement therapy and substrate-reduction therapy. The availability of these costly therapies has stimulated research regarding suitable biomarkers to monitor onset and progression of disease, as well as the efficacy of therapeutic intervention.

View Article and Find Full Text PDF

Although seizures in brain tumor patients are common, the knowledge on optimal anti-seizure therapy in this patient group is limited. An observational study was carried out using a database of all patients from the neuro-oncology service during the period 2000-2005, with data on seizure characteristics, therapy with AEDs, the underlying brain tumor and its treatment. A total of 140 brain tumor patients were studied of whom 23.

View Article and Find Full Text PDF

In tissue lesions of type I Gaucher patients, characteristic lipid-laden macrophages, 'Gaucher cells', are surrounded by inflammatory phagocytes. Gaucher cells secrete the elevated plasma chitotriosidase. The elevated plasma MIP-1beta in Gaucher patients stems from the phagocytes surrounding the Gaucher cells.

View Article and Find Full Text PDF