T lymphocytes recognize discrete regions on an antigen. The specificity of the T cell responses in three mouse strains of differing major histocompatibility complex (MHC) haplotype to a protein antigen, lysozyme, was analyzed using a series of peptides that walk the antigen in single amino acid steps. These peptide series were synthesized using the pin synthesis system, which was modified to al...

High-molecular-weight proteins having M protein reactivity were isolated without acid or alkaline digestion. Treatment of a heat-killed group A Streptococcus with sonic vibration released antigens which reacted strongly and specifically with absorbed type-specific antiserum. This antigen preparation was released without diminishing the total yield of acid-extractable M protein of the original h...

Only a few markers have been instrumental in the diagnosis of cancer. In contrast, tumor markers play a critical role in the monitoring of patients. The patient's clinical status and response to treatment can be evaluated rapidly using the tumor marker half-life (t(1/2)) and the tumor marker doubling time (DT). This report reviews the interest of determining these kinetic parameters for prostat...

The O antigen is a polymer with a repeated unit. The chain length in most Escherichia coli strains has a modal value of 10 to 18 O units, but other strains have higher or lower modal values. wzz (cld/rol) mutants have a random chain length distribution, showing that the modal distribution is determined by the Wzz protein. Cloned wzz genes from E. coli strains with short (7 to 16), intermediate ...

BACKGROUND Currently, the serodiagnosis of cystic echinococcosis relies mostly on crude Echinococcus granulosus hydatid cyst fluid as the antigen. Consequently, available immunodiagnostic tests lack standardization of the target antigen and, in turn, this is reflected on poor sensitivity and specificity of the serological diagnosis. METHODOLOGY/PRINCIPAL FINDINGS Here, a chromatographic metho...

The nano-structured vaccine delivery system, containing tomatine, n-octyl-β-Dglucopyranoside (OGP), phosphatidylethanolamine (PE), cholesterol, and ovalbumin (OVA), was examined in the present study. Transmission electron microscopy (TEM) and fluorescence microscopy were carried out to examine the nano-structures of this complex vaccine delivery system and its interactions with the antigen-pres...

A murine monoclonal antibody, 13.1, which blocks human natural killer (NK) cell-mediated lysis, has been developed. Hybridoma 13.1 was derived by fusion of NS-1 cells with spleen cells from mice immunized with an enriched population of NK cells. Supernatants of growing hybridomas were screened for their ability to block NK cell-mediated lysis of K562 targets. Antibody 13.1 is an IgG1 with a sin...

The immunodominant lipopolysaccharide is a key antigenic factor for Gram-negative pathogens such as salmonellae where it plays key roles in host adaptation, virulence, immune evasion, and persistence. Variation in the lipopolysaccharide is also the major differentiating factor that is used to classify Salmonella into over 2600 serovars as part of the Kaufmann-White scheme. While lipopolysacchar...

Escherichia coli O123 strains express a broad spectrum of phenotypes, H serotypes and virulence markers and are able to colonize and to cause disease in different hosts including humans. In this study, two subtypes of E. coli O123 antigen (group I and group II) have been identified based on their cross-reactions with other E. coli O antigens. Investigation of the relationship between O123 group...