Longevity and Mechanism of Heterosubtypic Protection Induced by M2SR (M2-Deficient Single-Replication) Live Influenza Virus Vaccine in Mice.

Seasonal influenza and the threat of global pandemics present a continuing threat to public health. However, conventional inactivated influenza vaccines (IAVs) provide little cross-protective immunity and suboptimal efficacy, even against well-matched strains. Furthermore, the protection against matched strains has been shown to be of a short duration in both mouse models and humans.

Repercussions of the COVID-19 pandemic on preventive health services in Brazil.

Introduction: The increasing burden of non-communicable diseases and limited public financing are major challenges facing health care systems in Latin America. Although COVID-19 severely impacted the Brazilian health care system, it is crucial to further characterize the degree of disruption caused to public health efforts, in order to address and manage long term effects of this pandemic. We therefore quantified the demand for preventive and treatment services from the Brazilian Unified Health System (Sistema Único de Saúde/SUS) in 2020 to evaluate potential repercussions of COVID-19 in this setting.

Post-acute COVID-19 syndrome after reinfection and vaccine breakthrough by the SARS-CoV-2 Gamma variant in Brazil.

We describe a case of prolonged COVID-19 caused by the SARS-CoV-2 Gamma variant in a fully vaccinated healthcare worker, 387 days after an infection caused by lineage B.1.1.

The Potential for Immunospecific Therapy in Multiple Sclerosis Based on Identification of Driver Clones of the Disease.

The autoimmune disease multiple sclerosis (MS) is driven by T cells that are reactive to self-antigens of the brain and spinal cord. Many drugs have been developed to treat MS, but we believe that immune-specific targeting of pathogenic T cells may be a better approach for treatment. This type of therapy identifies specific components of the self-reactive T-cell repertoire that would undergo similar natural selection criteria as those found in driver genes in cancer genesis.

Zika virus vertical transmission in children with confirmed antenatal exposure.

We report Zika virus (ZIKV) vertical transmission in 130 infants born to PCR+ mothers at the time of the Rio de Janeiro epidemic of 2015-2016. Serum and urine collected from birth through the first year of life were tested by quantitative reverse transcriptase polymerase chain reaction (PCR) and/or IgM Zika MAC-ELISA. Four hundred and seven specimens are evaluated; 161 sera tested by PCR and IgM assays, 85 urines by PCR.

Delayed childhood neurodevelopment and neurosensory alterations in the second year of life in a prospective cohort of ZIKV-exposed children.

We report neurodevelopmental outcomes in 216 infants followed since the time of PCR-confirmed maternal Zika virus (ZIKV) infection in pregnancy during the Rio de Janeiro epidemic of 2015-2016 (refs. ). Neurodevelopment was assessed by Bayley Scales of Infant and Toddler Development, third edition (Bayley-III; cognitive, language and motor domains) in 146 children and through neurodevelopment questionnaires/neurological examinations in 70 remaining children.

Zika virus and diagnostics.

Purpose Of Review: The purpose of this review is to present what is known about the Zika virus (ZIKV) at the time of writing this review. The viral structure and its phylogeny, as well as the limitations of current available techniques used for diagnosis, are discussed.

Recent Findings: Crystallography and cryo-electron microscopy of the whole ZIKV, or a few of its proteins, are confirming its overall antigenic relatedness to other flaviviruses.

Spectratyping analysis of the islet-reactive T cell repertoire in diabetic NOD Igμ(null) mice after polyclonal B cell reconstitution.

Background: Non Obese Diabetic mice lacking B cells (NOD.Igμ(null) mice) do not develop diabetes despite their susceptible background. Upon reconstitution of B cells using a chimera approach, animals start developing diabetes at 20 weeks of age.

Dietary aspartyl-phenylalanine-1-methyl ester delays osteoarthritis and prevents associated bone loss in STR/ORT mice.

Objective: STR/ORT mice provide a well-known model for murine idiopathic OA, with histological joint lesions resembling those of human OA. This model was used to investigate protective effects of the dipeptide aspartyl-phenylalanine-1-methyl ester (Asp-Phe-OMe or aspartame) via the oral route vs a regular diet.

Methods: STR/ORT mice were housed individually and fed diets with or without Asp-Phe-OMe (4 mg/kg), after weaning at the age of 3 weeks, until 15 months of age (average of 20 animals per group).

Treatment combining RU486 and Ad5IL-12 vector attenuates the growth of experimentally formed prostate tumors and induces changes in the sentinel lymph nodes of mice.

Background: Tumor immune responses are first generated and metastases often begin in tumor sentinel lymph nodes (TSLN). Therefore, it is important to promote tumor immunity within this microenvironment. Mifepristone (RU486) treatment can interfere with cortisol signaling that can lead to suppression of tumor immunity.

Altered peptide ligands can modify the Th2 T cell response to the immunodominant 161-175 peptide of LACK (Leishmania homolog for the receptor of activated C kinase).

Following Leishmania major infection, the early LACK (Leishmania homolog of receptors for activated C kinase)-induced IL-4 response appears to determine disease susceptibility in BALB/c mice. Therefore, we sought to manipulate the pathogenic T cell responses to the immunodominant epitope with the use of altered peptide ligands (APLs). Conservative and non-conservative substitutions for each amino acid of the LACK 161-175 peptide determinant were tested for their stimulatory capacity in four different LACK-reactive T cell systems.

Life-long systemic protection in mice vaccinated with L. major and adenovirus IL-12 vector requires active infection, macrophages and intact lymph nodes.

Immunization with soluble leishmanial antigen (SLA) in IFA plus Ad5IL-12 vector induced protection confined to the immunized footpad in BALB/c mice. However, animals that controlled a primary infection with a Leishmania major challenge in the same immunized footpad, became resistant to subsequent contralateral rechallenges due to expansion of IFN-gamma secreting cells. This systemic immunity could be disrupted either by macrophage depletion during immunization or by lymphadenectomy after challenge.

Selection of similar naive T cell repertoires but induction of distinct T cell responses by native and modified antigen.

To study the T cell responses induced by native and modified Ag, we have followed in vivo TCR selection and cytokine profile of T cells, as well as the isotype of induced Abs, in response to the model Ag hen egg-white lysozyme (HEL) and its reduced and carboxymethylated form (RCM-HEL). RCM-HEL induces in vivo a T cell response focused on the same immunodominant determinant characterizing the response to native HEL, but further skewed to the Th1 pathway. No difference between HEL and RCM-HEL could be observed in the efficiency of processing, nor in the type of APCs involved.

Nasal instillation of gpMBP can exacerbate murine EAE: effect of mucosal priming is an age-dependent phenomenon.

Nasal installation or oral feeding of antigens can alter the subsequent immune response in animals and humans. Most mucosal treatments with antigens tend to down-regulate disease, inducing full tolerance or immune deviation; however, priming has also been reported. We evaluated the course of experimental autoimmune encephalomyelitis (EAE) in (SJL x B10.

Strain-dependent effect of nasal instillation of antigen on the immune response in mice.

Background: Nasal instillation is an effective method for inducing antigen-specific immune tolerance. However, it is not clear how a tolerization scheme established in one mouse strain will perform when used in a mouse of a different haplotype.

Objectives: To compare the antigen-specific recall responses in four mouse strains--BALB/c, C57BL/6, NOD, and B10.