scholarly journals Disease inhibition by major histocompatibility complex binding peptide analogues of disease-associated epitopes: more than blocking alone.

1992 ◽  
Vol 176 (3) ◽  
pp. 667-677 ◽  
Author(s):  
M H Wauben ◽  
C J Boog ◽  
R van der Zee ◽  
I Joosten ◽  
A Schlief ◽  
...  
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
Major Histocompatibility ◽  
In Vitro Proliferation ◽  
Histocompatibility Complex ◽  
Disease Induction ◽  
Immunomodulatory Peptides ◽  
Peptide Analogues

Peptide analogues of disease-associated epitopes were studied for inhibition of experimental allergic encephalomyelitis (EAE) and adjuvant arthritis (AA) in Lewis rats. EAE- and AA-associated analogues were selected as competitors because of their in vitro inhibitory activity on proliferation of encephalitogenic and arthritogenic T cells. Although the EAE-associated competitor had a superior major histocompatibility complex (MHC) binding affinity, the AA-associated competitor was a better inhibitor of the in vitro proliferation of arthritogenic T cells. Furthermore, although in vivo EAE was inhibited by both competitors, AA was only inhibited by the AA-associated competitor. Remarkably, in contrast to what was expected of a regular MHC competitor peptide, the AA-associated peptide analogue also prevented AA upon immunization before disease induction and appeared to induce T cell responses that crossreacted with the original disease-associated epitope. Therefore, it is concluded that antigen-specific regulatory mechanisms were involved in synergy with MHC competition. The integration of both qualities into a single "competitor-modulator" analogue peptide may lead to the development of novel, more effective, disease-specific immunomodulatory peptides.

scholarly journals Major histocompatibility complex-specific prolongation of murine skin and cardiac allograft survival after in vivo depletion of V beta+ T cells.

1993 ◽  
Vol 177 (1) ◽  
pp. 35-44 ◽  
Author(s):  
J A Goss ◽  
R Pyo ◽  
M W Flye ◽  
J M Connolly ◽  
T H Hansen
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
Intraperitoneal Administration ◽  
Cell Receptor ◽  
Primary Response ◽  
Major Histocompatibility ◽  
Histocompatibility Complex ◽  
Allogeneic Response

The preferential usage of certain T cell receptor (TCR) V beta genes has been well established in several major histocompatibility complex (MHC)-restricted immune responses. However, V beta usage among allogeneic responses remains unclear. Because recent findings of ours and others indicate that V beta 8 predominates in certain Ld-restricted, peptide-specific responses, we examined the V beta 8 usage in allogeneic responses to Ld. To selectively recognize the Ld molecule, cells from BALB/c-H-2dm2 (dm2), the Ld-loss mutant mouse, were stimulated in vitro or in vivo with wild-type BALB/c cells. We report here that after the intraperitoneal administration of the anti-V beta 8 monoclonal antibody (mAb) F23.1, peripheral V beta 8 T cells were depleted from dm2 mice. This in vivo depletion abrogated the ability of dm2 splenocytes to mount a primary response to Ld molecules. This abrogation was specific, since the response of V beta 8-depleted dm2 cells to Kb/Db antigens was the same as that of control nondepleted dm2 cells. Furthermore, in vivo depletion of V beta 8 cells was found to cause a dramatic prolongation of Ld-disparate skin grafts (mean survival time [MST] 22.1 +/- 2.1 vs. 10.3 +/- 1.1 d for saline-treated controls, or 10.9 +/- 1.7 d for controls treated with mAb KJ23 to V beta 17). By contrast, V beta 8 depletion had no effect on recipients grafted with haplotype-mismatched skin or single Dk-locus-disparate skin. These findings demonstrate that V beta 8+ T cells predominate in allogeneic response to Ld but not other alloantigens. The effect of V beta 8 depletion was found to be even more dramatic on recipients grafted with Ld-disparate vascularized heart transplants (MST > 100 vs. 8.6 +/- 0.5 d for controls). In total, these findings establish the efficacy of using mAb to the V beta gene family to specifically and significantly enhance the survival of allografts. The implications of detecting V beta 8 usage in both alloreactive or MHC-restricted TCR responses to the same class I molecule are discussed.

Abstract 124: Parthenogenetic Stem Cell-derived Cardiomyocytes Express Major Histocompatibility Complex-I only after Inflammatory Stimulation

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Satish Galla ◽  
Michael Didie ◽  
Vijayakumar Muppala ◽  
Ralf Dressel ◽  
Wolfram Hubertus Zimmermann
Keyword(s):  
Major Histocompatibility Complex ◽  
Heart Muscle ◽  
Immunological Response ◽  
Type I ◽  
Major Histocompatibility ◽  
Adrenergic Stimulation ◽  
Mhc I ◽  
Histocompatibility Complex

Background: Pluripotent parthenogenetic stem cells (PSCs) can be directed towards a cardiac fate and utilized in tissue engineered heart repair. In vivo applications of tissue engineered allografts are compromised by expression of mismatching major histocompatibility complex proteins (MHC; encoded in the murine H2 locus). Here we investigated whether PSC-derived cardiomyocytes (CM) express MHC-I. Methods: Mouse PSCs (A3-line from B6D2F1 strain with haploidentical H2K d -locus) expressing a CM-specific neomycin-resistance and GFP were differentiated and purified for CM by addition of G418 (85% purity by FACS for actinin). To simulate heart muscle biology in vitro, we made use of engineered heart muscle (EHM) constructed from PSC-derived CM (75%), growth-inhibited murine embryonic fibroblasts (MEF (25%); NMRI mice), and collagen type I. MHC class-I H2K d (MHC-I) expression was assessed on CM and Non myocytes before EHM assembly and from enzymatically digested EHMs (cultured for 10 days) by FACS. Interferon gamma (IFNγ) was added for 48 h to stimulate MHC-I expression. As a reference, we investigated MHC-I expression in CM from neonatal mice and adult mouse hearts by FACS and by immunofluorescence staining. Results: EHM showed a positive ionotropic response to beta-adrenergic stimulation which could be reduced by muscarinergic stimulation. A3-CM, in contrast to Non myocytes, showed negligible expression of MHC-I (1±0.5% vs. 60±10% positive cells; n=3). EHM culture did not change MHC-I expression in CM. IFNγ treatment resulted in a marked increase of MHC-I-expression in CM monolayer culture (40±6%; n=3) and in EHM (30±8%; n=3). For comparison, 30% (n=2) neonatal CM expressed MHC-I while MHC-I was not detectable in adult CM. Conclusion: PSC-derived CM show a similarly low expression of MHC-I as adult CM and respond with MHC-I upregulation to IFNγ stimulation. This suggests a mature immunological response in PSC-CM with important implications for in vivo applications, i.e., MHC-I matching will likely be a prerequisite for successful allografting of PSC-EHM.

scholarly journals Major Histocompatibility Complex Haplotype Determines hsp70-Dependent Protection against Measles Virus Neurovirulence

2009 ◽  
Vol 83 (11) ◽  
pp. 5544-5555 ◽  
Author(s):  
Thomas Carsillo ◽  
Mary Carsillo ◽  
Zachary Traylor ◽  
Päivi Rajala-Schultz ◽  
Phillip Popovich ◽  
...  
Keyword(s):  
Major Histocompatibility Complex ◽  
Measles Virus ◽  
Protective Role ◽  
Major Histocompatibility ◽  
Major Histocompatibility Complex Haplotype ◽  
Brain Infection ◽  
Histocompatibility Complex ◽  
The Impact

ABSTRACT In vitro studies show that hsp70 promotes gene expression for multiple viral families, although there are few reports on the in vivo significance of virus-hsp70 interaction. Previously we showed that hsp70-dependent stimulation of Edmonston measles virus (Ed MeV) transcription caused an increased cytopathic effect and mortality in transgenic hsp70-overexpressing C57BL/6 mice (H-2 b ). The response to MeV infection is influenced by the major histocompatibility complex haplotype; H-2 d mice are resistant to brain infection due to robust antiviral immune responses, whereas H-2 b mice are susceptible due to deficiencies in this response. We therefore tested the hypothesis that the outcome of MeV-hsp70 interaction may be dependent upon the host H-2 haplotype. The impact of selective neuronal hsp70 overexpression on Ed MeV brain infection was tested with congenic C57BL/10 H-2 d neonatal mice. In this context, hsp70 overexpression conferred complete protection against virus-induced mortality, compared to >30% mortality in nontransgenic mice. Selective depletion of T-cell populations showed that transgenic mice exhibit a diminished reliance on T cells for protection. Brain transcript analysis indicated enhanced innate immune activation and signaling through Toll-like receptors 2 and 4 at early times postinfection for transgenic infected mice relative to those for nontransgenic infected mice. Collectively, results suggest that hsp70 can enhance innate antiviral immunity through Toll-like receptor signaling, supporting a protective role for physiological responses that enhance tissue levels of hsp70 (e.g., fever), and that the H-2 haplotype determines the effectiveness of this response.

scholarly journals Donor major histocompatibility complex (MHC) peptides are presented by recipient MHC molecules during graft rejection.

1992 ◽  
Vol 175 (1) ◽  
pp. 305-308 ◽  
Author(s):  
G Benichou ◽  
P A Takizawa ◽  
C A Olson ◽  
M McMillan ◽  
E E Sercarz
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
Critical Role ◽  
Major Histocompatibility ◽  
Skin Allograft ◽  
Mhc Molecules ◽  
Histocompatibility Complex ◽  
Molecular Therapies ◽  
Antigen Presenting

Peptides from donor major histocompatibility complex (MHC) molecules were examined for their activation of allogeneically primed T cells. After immunization with either allogeneic spleen cells or a skin allograft, primed T cells proliferate in response to peptides derived from polymorphic regions of alpha and beta chains of class II allo-MHC molecules. The results demonstrate that presentation of donor-MHC peptides by host-derived antigen-presenting cells is a common event in vivo. Thus, self-restricted T cell recognition of processed alloantigens may play a critical role in transplantation. An in-depth understanding of this response may result in the development of additional molecular therapies to combat allograft rejection.

scholarly journals T cells specific for alpha-beta interface regions of hemoglobin recognize the isolated subunit but not the tetramer and indicate presentation without processing

1989 ◽  
Vol 86 (17) ◽  
pp. 6729-6733 ◽  
Author(s):  
M Z Atassi ◽  
M Yoshioka ◽  
G S Bixler
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
T Cell ◽  
Cell Lines ◽  
Major Histocompatibility ◽  
Histocompatibility Complex ◽  
Oligomeric Protein ◽  
T Cell Lines ◽  
Antigen Presenting

Processing of a protein antigen into fragments is believed to be a prerequisite for its presentation by the antigen-presenting cell to the T cell. This model would predict that, in oligomeric proteins, T cells prepared with specificity for regions that are buried within subunit association surfaces should recognize the respective regions in vitro equally well on the isolated subunit or on the oligomer. Three hemoglobin (Hb) alpha-chain synthetic peptides, corresponding to areas that are situated either completely [alpha-(31-45)] or partially [alpha-(41-45) and alpha-(81-95)] within the interface between the alpha and beta subunits of Hb, and a fourth peptide representing a completely exposed area in tetrameric Hb were used as immunogens in SJL/J (H-2s) mice. Peptide-primed T cells were passaged in vitro with the respective peptide to obtain peptide-specific T-lymphocyte lines. T-cell clones were isolated from these lines by limiting dilution. T-cell lines and clones that were specific for buried regions in the subunit association surfaces recognized the free peptide and the isolated subunit but not the Hb tetramer. On the other hand, T cells with specificity against regions that are not involved in subunit interaction and are completely exposed in the tetramer recognized the peptide, the isolated subunit, and the oligomeric protein equally well. The responses of the T-cell lines and clones were major histocompatibility complex-restricted. Since the same x-irradiated antigen-presenting cells were employed, the results could not be attributed to differences or defects in Hb processing. The findings indicate that in vitro the native (unprocessed and undissociated) oligomeric protein was the trigger of major histocompatibility complex-restricted T-cell responses.

scholarly journals Major Histocompatibility Complex–independent Recognition of a Distinctive Pollen Antigen, Most Likely a Carbohydrate, by Human CD8+ α/β T Cells

1997 ◽  
Vol 186 (6) ◽  
pp. 899-908 ◽  
Author(s):  
Silvia Corinti ◽  
Raffaele De Palma ◽  
Angelo Fontana ◽  
Maria Cristina Gagliardi ◽  
Carlo Pini ◽  
...  
Keyword(s):  
T Cells ◽  
Major Histocompatibility Complex ◽  
T Cell ◽  
Cd8 T Cells ◽  
T Cell Response ◽  
Major Histocompatibility ◽  
T Cell Clones ◽  
Histocompatibility Complex ◽  
Cell Clones

We have isolated CD8+ α/β T cells from the blood of atopic and healthy individuals which recognize a nonpeptide antigen present in an allergenic extract from Parietaria judaica pollen. This antigen appears to be a carbohydrate because it is resistant to proteinase K and alkaline digestion, is hydrophilic, and is sensitive to trifluoromethane-sulphonic and periodic acids. In addition, on a reverse-phase high performance liquid chromatography column the antigen recognized by CD8+ T cells separates in a fraction which contains >80% hexoses (glucose and galactose) and undetectable amounts of proteins. Presentation of this putative carbohydrate antigen (PjCHOAg) to CD8+ T cell clones is dependent on live antigen presenting cells (APCs) pulsed for >1 h at 37°C, suggesting that the antigen has to be internalized and possibly processed. Indeed, fixed APCs or APCs pulsed at 15°C were both unable to induce T cell response. Remarkably, PjCHOAg presentation is independent of the expression of classical major histocompatibility complex (MHC) molecules or CD1. CD8+ T cells stimulated by PjCHOAg-pulsed APCs undergo a sustained [Ca2+]i increase and downregulate their T cell antigen receptors (TCRs) in an antigen dose– and time-dependent fashion, similar to T cells stimulated by conventional ligands. Analysis of TCR Vβ transcripts shows that six independent PjCHOAg-specific T cell clones carry the Vβ8 segment with a conserved motif in the CDR3 region, indicating a structural requirement for recognition of this antigen. Finally, after activation, the CD8+ clones from the atopic patient express CD40L and produce high levels of interleukins 4 and 5, suggesting that the clones may have undergone a Th2-like polarization in vivo. These results reveal a new class of antigens which triggers T cells in an MHC-independent way, and these antigens appear to be carbohydrates. We suggest that this type of antigen may play a role in the immune response in vivo.

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