Expression of la Antigens on T and B Cells and their Relationship to Immune-Response Functions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73337/1/j.1600-065X.1976.tb00217.x.pd

The relationship of the major murine histocompatibility region associated IA antigens to mitogen responses

Genes located in the I region of the H-2 complex control a system of lymphocyte alloantigens (Ia) which are expressed on subpopulations of T and B cells. Specific anti-Ia serum plus rabbit complement removed the B-lymphocyte population responsive to the mitogen LPS and the subpopulation of T cells responsive to Con-A. Lymphocytes sensitive to PHA or leucoagglutinin were not removed by anti-Ia serum and complement. Significant inhibition of the proliferative response to LPS was also obtained by brief periods of cell pretreatment with anti-Ia antibodies without complement. This inhibition was specific with the appropriate anti-Ia serum and did not occur with anti-H-2K sera or when cells of a different I region were pretreated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21764/1/0000158.pd

Virus-specific, CD8+ major histocompatibility complex class I-restricted cytotoxic T lymphocytes in lymphocytic choriomeningitis virus-infected beta2-microglobulin-deficient mice.

Following infection with lymphocytic choriomeningitis virus (LCMV), normal adult mice generate virus-specific, major histocompatibility complex (MHC) class I-restricted cytotoxic T lymphocytes (CTL) which clear the virus after intraperitoneal infection or cause death following intracranial (i.c.) infection. We have investigated the response of beta2-microglobulin-deficient (beta2m-) mice of the H-2d haplotype (KOD mice) to LCMV infection. Unlike H-2b beta2m- mice, which generate CD4+ MHC class II-restricted CTL in response to LCMV, KOD mice generate high levels of CD8+ MHC class I-restricted, virus-specific CTL. These CTL are specific for the LCMV nucleoprotein epitope (residues 118 to 126) in association with the Ld class I molecule, analogous to the CTL response in wild-type mice. KOD mice are also susceptible to lethal LCM disease, with 75 to 80% of the mice dying 7 to 9 days following i.c. infection with virus. Similar to results with normal mice, lethal LCM disease in KOD mice is prevented by in vivo depletion of CD8+ T cells prior to i.c. infection. In contrast to wild-type mice, however, KOD mice cannot control LCMV and become persistently infected. Overall, these results demonstrate that beta2m is not an absolute requirement for presentation of endogenous antigen on Ld or for induction of virus-specific Ld-restricted CTL in vivo

Con A induced suppressor cells: Suppression with I region incompatibility

Allogeneic Con A induced suppressor cells differing in the I and S region but not H-2K or H-2D regions were as efficient as syngeneic cells in suppressing the secondary IgM and IgG response to burro erythrocytes. Con A activated suppressor cells were not sensitive to anti-Ia serum and complement. However, if the spleen cell population was treated with anti-Ia serum and complement before stimulation with Con A, suppressor cells were not generated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22960/1/0000527.pd

Allelic diversity at the DLA-88 locus in Golden Retriever and Boxer breeds is limited

In the dog, previous analyses of major histocompatibility complex (MHC) class I genes suggest a single polymorphic locus, Dog Leukocyte Antigen (DLA)-88. While 51 alleles have been reported, estimates of prevalence have not been made. We hypothesized that, within a breed, DLA-88 diversity would be restricted, and one or more dominant alleles could be identified. Accordingly, we determined allele usage in 47 Golden Retrievers and 39 Boxers. In each population, 10 alleles were found; 4 were shared. Seven novel alleles were identified. DLA-88*05101 and *50801 predominated in Golden Retrievers, while most Boxers carried *03401. In these breeds DLA-88 polymorphisms are limited and largely non-overlapping. The finding of highly prevalent alleles fulfills an important prerequisite for studying canine CD8+ T-cell responses

Heterotypic Humoral and Cellular Immune Responses following Norwalk Virus Infection

Norovirus immunity is poorly understood as the limited data available on protection after infection are often contradictory. In contrast to the more prominent GII noroviruses, GI norovirus infections are less frequent in outbreaks. The GI noroviruses display very complex patterns of heterotypic immune responses following infection, and many individuals are highly susceptible to reinfection. To study the immune responses and mechanisms of GI.1 persistence, we built structural models and recombinant virus-like particles (VLPs) of five GI strains: GI.1-1968, GI.1-2001, GI.2-1999, GI.3-1999, and GI.4-2000. Structural models of four GI genotype capsid P domain dimers suggested that intragenotype structural variation is limited, that the GI binding pocket is mostly preserved between genotypes, and that a conserved, surface-exposed epitope may allow for highly cross-reactive immune responses. GI VLPs bound to histo-blood group antigens (HBGAs) including fucose, Lewis, and A antigens. Volunteers infected with GI.1-1968 (n = 10) had significant increases between prechallenge and convalescent reactive IgG for all five GI VLPs measured by enzyme immunoassay. Potential cross-neutralization of GI VLPs was demonstrated by convalescent-phase serum cross-blockade of GI VLP-HBGA interaction. Although group responses were significant for all GI VLPs, each individual volunteer demonstrated a unique VLP blockade pattern. Further, peripheral blood mononuclear cells (PBMCs) were stimulated with each of the VLPs, and secretion of gamma interferon (IFN-γ) was measured. As seen with blockade responses, IFN-γ secretion responses differed by individual. Sixty percent responded to at least one GI VLP, with only two volunteers responding to GI.1 VLP. Importantly, four of five individuals with sufficient PBMCs for cross-reactivity studies responded more robustly to other GI VLPs. These data suggest that preexposure history and deceptive imprinting may complicate PBMC and B-cell immune responses in some GI.1-1968-challenged individuals and highlight a potential complication in the design of efficacious norovirus vaccines

Flagellin Treatment Prevents Increased Susceptibility to Systemic Bacterial Infection after Injury by Inhibiting Anti-Inflammatory IL-10+ IL-12- Neutrophil Polarization

Severe trauma renders patients susceptible to infection. In sepsis, defective bacterial clearance has been linked to specific deviations in the innate immune response. We hypothesized that innate immune modulations observed during sepsis also contribute to increased bacterial susceptibility after severe trauma. A well-established murine model of burn injury, used to replicate infection following trauma, showed that wound inoculation with P. aeruginosa quickly spreads systemically. The systemic IL-10/IL-12 axis was skewed after burn injury with infection as indicated by a significant elevation in serum IL-10 and polarization of neutrophils into an anti-inflammatory (“N2”; IL-10+ IL-12−) phenotype. Infection with an attenuated P. aeruginosa strain (ΔCyaB) was cleared better than the wildtype strain and was associated with an increased pro-inflammatory neutrophil (“N1”; IL-10−IL-12+) response in burn mice. This suggests that neutrophil polarization influences bacterial clearance after burn injury. Administration of a TLR5 agonist, flagellin, after burn injury restored the neutrophil response towards a N1 phenotype resulting in an increased clearance of wildtype P. aeruginosa after wound inoculation. This study details specific alterations in innate cell populations after burn injury that contribute to increased susceptibility to bacterial infection. In addition, for the first time, it identifies neutrophil polarization as a therapeutic target for the reversal of bacterial susceptibility after injury

HLA-A2-Matched Peripheral Blood Mononuclear Cells From Type 1 Diabetic Patients, but Not Nondiabetic Donors, Transfer Insulitis to NOD-scid/ cnull/HLA-A2 Transgenic Mice Concurrent With the Expansion of Islet-Specific CD8+ T cells

OBJECTIVEType 1 diabetes is an autoimmune disease characterized by the destruction of insulin-producing β-cells. NOD mice provide a useful tool for understanding disease pathogenesis and progression. Although much has been learned from studies with NOD mice, increased understanding of human type 1 diabetes can be gained by evaluating the pathogenic potential of human diabetogenic effector cells in vivo. Therefore, our objective in this study was to develop a small-animal model using human effector cells to study type 1 diabetes.RESEARCH DESIGN AND METHODSWe adoptively transferred HLA-A2–matched peripheral blood mononuclear cells (PBMCs) from type 1 diabetic patients and nondiabetic control subjects into transgenic NOD-scid/γcnull/HLA-A*0201 (NOD-scid/γcnull/A2) mice. At various times after adoptive transfer, we determined the ability of these mice to support the survival and proliferation of the human lymphoid cells. Human lymphocytes were isolated and assessed from the blood, spleen, pancreatic lymph node and islets of NOD-scid/γcnull/A2 mice after transfer.RESULTSHuman T and B cells proliferate and survive for at least 6 weeks and were recovered from the blood, spleen, draining pancreatic lymph node, and most importantly, islets of NOD-scid/γcnull/A2 mice. Lymphocytes from type 1 diabetic patients preferentially infiltrate the islets of NOD-scid/γcnull/A2 mice. In contrast, PBMCs from nondiabetic HLA-A2–matched donors showed significantly less islet infiltration. Moreover, in mice that received PBMCs from type 1 diabetic patients, we identified epitope-specific CD8+ T cells among the islet infiltrates.CONCLUSIONSWe show that insulitis is transferred to NOD-scid/γcnull/A2 mice that received HLA-A2–matched PBMCs from type 1 diabetic patients. In addition, many of the infiltrating CD8+ T cells are epitope-specific and produce interferon-γ after in vitro peptide stimulation. This indicates that NOD-scid/γcnull/A2 mice transferred with HLA-A2–matched PBMCs from type 1 diabetic patients may serve as a useful tool for studying epitope-specific T-cell–mediated responses in patients with type 1 diabetes

HLA-A2–Matched Peripheral Blood Mononuclear Cells From Type 1 Diabetic Patients, but Not Nondiabetic Donors, Transfer Insulitis to NOD-scid/γcnull/HLA-A2 Transgenic Mice Concurrent With the Expansion of Islet-Specific CD8+ T cells

OBJECTIVE: Type 1 diabetes is an autoimmune disease characterized by the destruction of insulin-producing beta-cells. NOD mice provide a useful tool for understanding disease pathogenesis and progression. Although much has been learned from studies with NOD mice, increased understanding of human type 1 diabetes can be gained by evaluating the pathogenic potential of human diabetogenic effector cells in vivo. Therefore, our objective in this study was to develop a small-animal model using human effector cells to study type 1 diabetes. RESEARCH DESIGN AND METHODS: We adoptively transferred HLA-A2-matched peripheral blood mononuclear cells (PBMCs) from type 1 diabetic patients and nondiabetic control subjects into transgenic NOD-scid/gammac(null)/HLA-A*0201 (NOD-scid/gammac(null)/A2) mice. At various times after adoptive transfer, we determined the ability of these mice to support the survival and proliferation of the human lymphoid cells. Human lymphocytes were isolated and assessed from the blood, spleen, pancreatic lymph node and islets of NOD-scid/gammac(null)/A2 mice after transfer. RESULTS: Human T and B cells proliferate and survive for at least 6 weeks and were recovered from the blood, spleen, draining pancreatic lymph node, and most importantly, islets of NOD-scid/gammac(null)/A2 mice. Lymphocytes from type 1 diabetic patients preferentially infiltrate the islets of NOD-scid/gammac(null)/A2 mice. In contrast, PBMCs from nondiabetic HLA-A2-matched donors showed significantly less islet infiltration. Moreover, in mice that received PBMCs from type 1 diabetic patients, we identified epitope-specific CD8(+) T cells among the islet infiltrates. CONCLUSIONS: We show that insulitis is transferred to NOD-scid/gammac(null)/A2 mice that received HLA-A2-matched PBMCs from type 1 diabetic patients. In addition, many of the infiltrating CD8(+) T cells are epitope-specific and produce interferon-gamma after in vitro peptide stimulation. This indicates that NOD-scid/gammac(null)/A2 mice transferred with HLA-A2-matched PBMCs from type 1 diabetic patients may serve as a useful tool for studying epitope-specific T-cell-mediated responses in patients with type 1 diabetes