scholarly journals Immunogenic and Protective Potential of Mutans Streptococcal Glucosyltransferase Peptide Constructs Selected by Major Histocompatibility Complex Class II Allele Binding

2006 ◽  
Vol 75 (2) ◽  
pp. 915-923 ◽  
Author(s):  
S. Culshaw ◽  
K. LaRosa ◽  
H. Tolani ◽  
X. Han ◽  
J. W. Eastcott ◽  
...  

ABSTRACT Mutans streptococcal glucosyltransferases (GTF) have been demonstrated to be effective components of dental caries vaccines. We had previously selected peptide subunits of GTF for vaccine development based on putative functional significance and conservation of GTF primary structure among enzyme isoforms. In this study, 20 20-mer linear GTF peptides were synthesized, 17 identified on the basis of the highest potential major histocompatibility complex (MHC) class II-binding activity using computer-generated algorithms (Epimatrix and ProPred) and 3 with previously demonstrated functional significance. The immunoreactivities of these peptides were explored with rodent systems. Sera from GTF-immunized rats, assessed for binding to linear peptides by enzyme-linked immunosorbent assay, demonstrated immunoglobulin G antibody reactivity with peptides 6 and 11 and a T-cell proliferation response to peptides 6, 9, 11, and 16. Multiple antigenic peptide (MAP) constructs were synthesized from promising linear sequences. Rats that were immunized with MAP 7, 11, or 16, respectively, responded well to the immunizing MAP. Most importantly, a robust immune response (antibody and T-cell proliferation) was observed to native GTF following MAP 11 (amino acids 847 to 866; VVINNDKFVSWGITDFEM) immunization. This response inhibited GTF enzyme function. Two dental caries pathogenesis experiments were performed wherein rats were immunized with MAP constructs 11, 16, and/or 11 plus 16, followed by infection with cariogenic Streptococcus sobrinus. In both experiments cariogenic bacterial recoveries were reduced relative to total streptococci in the MAP 11- and MAP 11 plus 16-immunized groups, and the extent of dental caries was also significantly reduced in these groups. Thus, we have identified a peptide with projected avid MHC-binding activity that elicited immunoreactivity with native GTF and demonstrated protection against dental caries infection after immunization, implying that this peptide may be important in a subunit dental caries vaccine.

2000 ◽  
Vol 44 (4) ◽  
pp. 1067-1069 ◽  
Author(s):  
Teresa Krakauer

ABSTRACT Proinflammatory cytokines mediate the toxic effect of superantigenic staphylococcal exotoxins (SE). TJU103, a small nonpeptidic molecule that blocks the interaction between major histocompatibility complex class II and CD4 molecules inhibited SE-stimulated T-cell proliferation (by 92%) and production of tumor necrosis factor, interleukin 1β, interleukin 6, and gamma interferon (by 66, 56, 76, and 72%, respectively) by human peripheral blood mononuclear cells. These data suggest that TJU103 may be useful for mitigating the pathogenic effects of SE.


1992 ◽  
Vol 175 (6) ◽  
pp. 1707-1715 ◽  
Author(s):  
E Barzaga-Gilbert ◽  
D Grass ◽  
S K Lawrance ◽  
P A Peterson ◽  
E Lacy ◽  
...  

Murine T cell responses to human class II major histocompatibility complex (MHC) molecules were shown to be a minimum of 20-70-fold lower than responses to allogeneic molecules. Transgenic mice expressing slightly below normal (75-95%) or very high (250-380%) cell surface levels of human CD4 were utilized to determine whether this was due to a species-specific interaction between murine CD4 and class II molecules. Human CD4 was shown to function in signal transduction events in murine T cells based on the ability of anti-human CD4 antibody to synergize with suboptimal doses of anti-murine CD3 antibody in stimulating T cell proliferation. In mice expressing lower levels of human CD4, T cell responses to human class II molecules were enhanced up to threefold, whereas allogeneic responses were unaltered. In mice expressing high levels of human CD4, responses to human class II molecules were enhanced at least 10-fold, whereas allogeneic responses were between one and three times the level of normal responses. The relatively greater enhancement of the response to human class II molecules in both lines argues for a preferential interaction between human CD4 and human class II molecules. In mice expressing lower levels of human CD4, responses to human class II molecules were blocked by antibodies to CD4 of either species, indicating participation by both molecules. In mice expressing high levels of human CD4, responses to both human and murine class II molecules were almost completely blocked with anti-human CD4 antibody, whereas anti-murine CD4 antibody had no effect. However, anti-murine CD4 continued to synergize with anti-CD3 in stimulating T cell proliferation in these mice. Thus, overexpression of human CD4 selectively impaired the ability of murine CD4 to assist in the process of antigen recognition. The ability of human CD4 to support a strong allogeneic response under these conditions indicates that this molecule can interact with murine class II molecules to a significant extent. Despite the fact that human CD4 appeared to be the only functional coreceptor in these mice, responses to human class II molecules were still much lower than those to murine class II alloantigens. This indicates that species-specific interactions between class II molecules and CD4 expressed on peripheral T cells are not sufficient to account for the low xenogeneic response and that intrinsic differences in T cell receptor structures or the need for species specificity in the interaction between CD4 and class II molecules during positive selection are also important.


2014 ◽  
Vol 21 (5) ◽  
pp. 641-650 ◽  
Author(s):  
Rachel M. Stenger ◽  
Hugo D. Meiring ◽  
Betsy Kuipers ◽  
Martien Poelen ◽  
Jacqueline A. M. van Gaans-van den Brink ◽  
...  

ABSTRACTKnowledge of naturally processedBordetella pertussis-specific T cell epitopes may help to increase our understanding of the basis of cell-mediated immune mechanisms to control this reemerging pathogen. Here, we elucidate for the first time the dominant major histocompatibility complex (MHC) class II-presentedB. pertussisCD4+T cell epitopes, expressed on human monocyte-derived dendritic cells (MDDC) after the processing of whole bacterial cells by use of a platform of immunoproteomics technology. Pertussis epitopes identified in the context of HLA-DR molecules were derived from two envelope proteins, i.e., putative periplasmic protein (PPP) and putative peptidoglycan-associated lipoprotein (PAL), and from two cytosolic proteins, i.e., 10-kDa chaperonin groES protein (groES) and adenylosuccinate synthetase (ASS). No epitopes were detectable from known virulence factors. CD4+T cell responsiveness in healthy adults against peptide pools representing epitope regions or full proteins confirmed the immunogenicity of PAL, PPP, groES, and ASS. Elevated lymphoproliferative activity to PPP, groES, and ASS in subjects within a year after the diagnosis of symptomatic pertussis suggested immunogenic exposure to these proteins during clinical infection. The PAL-, PPP-, groES-, and ASS-specific responses were associated with secretion of functional Th1 (tumor necrosis factor alpha [TNF-α] and gamma interferon [IFN-γ]) and Th2 (interleukin 5 [IL-5] and IL-13) cytokines. Relative paucity in the naturalB. pertussisepitope display of MDDC, not dominated by epitopes from known protective antigens, can interfere with the effectiveness of immune recognition ofB. pertussis. A more complete understanding of hallmarks inB. pertussis-specific immunity may advance the design of novel immunological assays and prevention strategies.


1994 ◽  
Vol 24 (9) ◽  
pp. 2213-2218 ◽  
Author(s):  
Amin Rahemtulla ◽  
Thomas M. Kündig ◽  
Arumugabadiv Narendran ◽  
Martin F. Bachmann ◽  
Michael Julius ◽  
...  

1983 ◽  
Vol 158 (2) ◽  
pp. 428-437 ◽  
Author(s):  
S R Abromson-Leeman ◽  
H Cantor

We have analyzed a panel of T cell clones that corecognize defined epitopes of the insulin molecule in association with Ia for their patterns of recognition of alloantigens. A striking correlation is observed between recognition of the I-Ab gene product and cow insulin alpha loop and recognition of I-Eu of the PL/J haplotype. These results are consistent with the notion that reactions to foreign major histocompatibility complex (MHC) products reflect molecular mimicry by foreign class II antigens of 'physiologic' complexes formed by autologous class II MHC molecules and antigen.


1995 ◽  
Vol 181 (2) ◽  
pp. 641-648 ◽  
Author(s):  
M A Maldonado ◽  
R A Eisenberg ◽  
E Roper ◽  
P L Cohen ◽  
B L Kotzin

Mice homozygous for the lpr gene have a defect in fas (CD95), a cell surface receptor that belongs to the tumor necrosis factor receptor family and that mediates apoptosis. This genetic abnormality results in lymphoproliferation characterized by the accumulation of CD4-CD8- (double negative [DN]) T cells, autoantibody production, and background strain-dependent, end-organ disease. Our previous results suggested that major histocompatibility complex (MHC) class I may be involved in the development of DN cells. To test this hypothesis, we derived C57BL/6-lpr/lpr (B6/lpr) mice that were deficient for the beta 2-microglobulin gene (beta 2m lpr) and had no detectable class I expression. At 6 mo of age, compared with B6/lpr littermates with normal class I genes, these mice showed greatly reduced lymphadenopathy, mostly due to a dramatic decrease in the number of DN cells. Significant changes in the percentage of other T cell subsets were noted, but only gamma/delta+ T cells showed a marked increase in both percentage and absolute numbers. Analysis of T cell receptor V beta expression of the remaining DN T cells in beta 2m -lpr mice showed a shift to a CD4-like repertoire from a CD8-like repertoire in control B6/lpr mice, indicating that a small MHC class II selected DN population was unmasked in lpr mice lacking class I. We also found that the production of immunoglobulin G (IgG) autoantibodies (antichromatin and anti-single stranded DNA), total IgG and IgG2a, but not total IgM or IgM rheumatoid factor, was significantly reduced in the beta 2m -lpr mice. This work suggests that >90% of DN T cells in lpr mice are derived from the CD8 lineage and are selected on class I. However, a T cell subset selected on class II and T cells expressing gamma/delta are also affected by the lpr defect and become minor components of the aberrant DN population.


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