Curr Top Microbiol Immunol
October 2024
Controlled human infection studies have contributed significantly to the understanding of pathogeneses and treatment of infectious diseases. In malaria, deliberately infecting humans with malaria parasites was used as a treatment for neurosyphilis in the early 1920s. More recently, controlled human malaria infection (CHMI) has become a valuable, cost-effective tool to fast-track the development and evaluation of new anti-malarial drugs and/or vaccines.
View Article and Find Full Text PDFThe advances in high-throughput DNA sequencing and recombinant antibody technologies has presented new methods for characterizing antibody repertoires and significantly increased our understanding on the functional role of antibodies in immunity and their use in diagnostics, vaccine antigen design and as biological therapeutics. A subset of Bos taurus antibodies possesses unique ultra-long third complementary-determining region of the heavy chain (CDRH3) and are of special interest because they are thought to have unique functional abilities of broadly neutralizing properties - a functional role that has not been fully explored in vaccine development. Next generation sequencing technologies that are widely used to profile immunoglobulin (Ig) repertoires are based on short-read methods such as the Illumina technology.
View Article and Find Full Text PDFHaemophilus influenzae type b (Hib) is now recognized as an important pathogen in Asia. To evaluate disease susceptibility, and as a marker of Hib transmission before routine immunization was introduced in Kathmandu, 71 participants aged 7 months-77 years were recruited and 15 cord blood samples were collected for analysis of anti-polyribosylribitol phosphate antibody levels by enzyme-linked immunosorbent assay. Only 20% of children under 5 years old had levels considered protective (>0.
View Article and Find Full Text PDFPediatr Infect Dis J
July 2013
Background: Maternal antibodies give neonates some protection against bacterial infection. We measured antibodies against Neisseria meningitidis serogroups A, C, Y and W135 in mothers and their 2-month-old infants at study enrollment. We also assessed the impact of maternal antibody present at 2 months of age on the immune response to a primary course of quadrivalent meningococcal conjugate vaccine (MenACWY-CRM197) given at 2 and 4 months of age.
View Article and Find Full Text PDFThe maintenance of adequate serum Ab levels following immunization has been identified as the most important mechanism for individual long-term protection against rapidly invading encapsulated bacteria. The mechanisms for maintaining adequate serum Ab levels and the relationship between Ag-specific memory B cells and Ab at steady state are poorly understood. We measured the frequency of circulating serogroup C meningococcal (MenC)-specific memory B cells in 250 healthy 6- to 12-y-old children 6 y following MenC conjugate vaccine priming, before a booster of a combined Haemophilus influenzae type b-MenC conjugate vaccine and then 1 wk, 1 mo, and 1 y after the booster.
View Article and Find Full Text PDFIn contrast to other pneumococcal serotypes, which are thought to be T-independent antigens, type 1 Streptococcus pneumoniae polysaccharide (Sp1) is a zwitterionic polysaccharide (ZPS). It has previously been shown to be processed and presented by antigen-presenting cells utilizing the MHC-II pathway, which leads to Sp1-induced T cell proliferation, a hallmark of thymus-dependent immune responses. We used peripheral blood mononuclear cells obtained from adults enrolled in a randomised clinical trial to investigate memory B cell responses following immunisation with the 23-valent pneumococcal plain polysaccharide vaccine.
View Article and Find Full Text PDFBackground: It is not known how long children with Haemophilus influenzae serotype b (Hib) vaccine failure retain protective Hib antibody concentrations after infection. The objective of this study was to determine Hib antibody concentrations in children several years after infection and to identify risk factors for low antibody concentrations.
Methods: The families of children from the United Kingdom who developed invasive Hib disease after prior immunization with Hib conjugate vaccine (i.