Biomedical subjects

Ryuji Suzuki

Publications and source records attributed to Ryuji Suzuki.

At least 19 recordsLinked to original sources

PubMed2006

Comparison of CDR3 length among thymocyte subpopulations: impacts of MHC and BV segment on the CDR3 shortening.

Thymocytes are thought to be selected on the basis of antigen specificity between TCR and peptide-MHC (pMHC) ligands. The specificity depends primarily on extensive diversities of complementarity determining region 3 (CDR3), whose specificity is considered to be determined through thymocyte selection. We examined the CDR3 length profiles with 20 BV segments in thymocyte subpopulations from C57BL/6 (H-2(b)), C.B10 (Balb/c congenic, H-2(b)) and Balb/c (H-2(d)) mice. The CDR3 length was shorter in both CD4 single positive (SP) and CD8SP than in double positive (DP), but not altered among DP, double negative (DN) 4 and DN3 subpopulations. The CDR3 shortened more prominently in CD4SP than in CD8SP for C57BL/6 and C.B10, but the shortening was only slight for Balb/c. Although the shortening varied considerably among different BV segments, the greater shortening was observed in most BV segments for CD4SP and in several for CD8SP, in particular, the extent was the greatest in BV1, BV2, BV15, BV16, BV23 and BV26 for CD4SP, and in BV13-1 and BV29 for CD8SP. Moreover, the extent and the pattern of CDR3 shortening were basically the same among highly homologous BV segments (e.g. BV12-1 and 12-2; BV13-1, 13-2 and 13-3). These results taken together indicate that (1) the CDR3 shortening occurred between the DP to the SP stages but never earlier, that (2) there would be the MHC class preference for the CDR3 shortening, that (3) it was in part influenced by MHC haplotype, and finally that (4) the primary structure of particular BV segments would possibly affect the CDR3 length in selected thymocytes. It could be deduced from these results that the CDR3 shortening might play roles in ensuring geometrical disposition of CDRs unique to each BV segment and consequently allow CDRs to intimately interact with pMHC ligands.

Animals↗

PubMed2006

Isolation and expression profiling of genes upregulated in bone marrow-derived mononuclear cells of rheumatoid arthritis patients.

We have comprehensively identified the genes whose expressions are augmented in bone marrow-derived mononuclear cells (BMMC) from patients with Rheumatoid Arthritis (RA) as compared with BMMCs from Osteoarthritis (OA) patients, and named them AURA after augmented in RA. Both stepwise subtractive hybridization and microarray analyses were used to identify AURA genes, which were confirmed by northern blot analysis and/or reverse transcription polymerase chain reaction (RT-PCR). We also assessed their expression levels in individual patients by quantitative real-time RT-PCR. Of 103 AURA genes we have identified, the mRNA levels of the following 10 genes, which are somehow related to immune responses, were increased in many of the RA patients: AREG (=AURA9), FK506-binding protein 5 (FKBP5 = AURA45), C-type lectin superfamily member 9 (CLECSF9 = AURA24), tyrosylprotein sulfotransferase 1 (TPST1 = AURA52), lymphocyte G0/G1 switch gene (G0S2 = AURA8), chemokine receptor 4 (CXCR4 = AURA86), nuclear factor-kappa B (NF-kappaB = AURA25) and two genes of unknown function (FLJ11106 = AURA1, BC022398 = AURA2 and XM_058513 = AURA17). Since AREG was most significantly increased in many of the RA patients, we subjected it to further analysis and found that AREG-epidermal growth factor receptor signaling is highly activated in synovial cells isolated from RA patients, but not in OA synoviocytes. We propose that the expression profiling of these AURA genes may improve our understanding of the pathogenesis of RA.

Amphiregulin↗

PubMed2006

Pro-inflammatory cytokine tumor necrosis factor-alpha induces bone morphogenetic protein-2 in chondrocytes via mRNA stabilization and transcriptional up-regulation.

In articular chondrocytes, the inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) induces the expression of bone morphogenetic protein-2 (BMP-2), a growth factor known to be involved in the induction of cartilage and bone. A study was performed to clarify the mechanism(s) underlying the induction of BMP-2 in chondrogenic ATDC5 cells and primary cultured adult human articular chondrocytes. In ATDC5 cells, the endogenous BMP-2 expression was consistently low throughout the process of chondrogenic differentiation, and TNF-alpha induced BMP-2 expression only after the cells acquired the chondrogenic phenotype. The results of nuclear run-off assay and cycloheximide treatment consistently indicated that ATDC5 cells acquire the capacity to synthesize BMP-2 mRNA in the nuclei during the differentiation process. In an attempt to explain the discrepancy between the active nuclear mRNA synthesis and the observed low expression level in differentiated ATDC5 cells, the stability of BMP-2 mRNA was evaluated, and the cells were found to regulate the expression of BMP-2 at the post-transcriptional level. Human chondrocytes were confirmed to have a similar post-transcriptional regulation. The result of 3'-rapid amplification of cDNA end revealed that both human and mouse BMP-2 mRNAs contain multiple pentameric AUUUA motifs in a conserved manner in the 3'-untranslated regions, and transient transfection experiments demonstrated that TNF-alpha increases the stability of BMP-2 mRNA through the pentameric motifs. Further experiments revealed that TNF-alpha modulates mRNA stability via p38 signal transduction pathway, whereas the cytokine also augmented the expression of BMP-2 through transcriptional up-regulation via the transcriptional factor NF-kappaB.

3' Untranslated Regions↗

PubMed2006

Src homology 2 domain-containing protein tyrosine phosphatase substrate 1 regulates the induction of Langerhans cell maturation.

Recently, we reported that Src homology 2 domain-containing protein tyrosine phosphatase substrate 1 (SHPS-1) plays an important role in the migration of Langerhans cells (LC). Here, we show that SHPS-1 is involved in the maturation of LC. Immunofluorescence analysis on epidermal sheets for I-A or CD86 revealed that LC maturation induced by 2,4-dinitro-1-fluorobenzene (DNFB) or by TNF-alpha was inhibited by pretreatment with an anti-SHPS-1 monoclonal antibody (mAb) or with CD47-Fc fusion protein, a ligand for SHPS-1. Further, FACS analysis demonstrated that I-A(+) LC that had emigrated from skin explants expressed CD80 or CD86, whereas CD47-Fc protein reduced CD80(high+) or CD86(high+) cells. CD47-Fc protein also reduced the up-regulation of surface CD80 or CD86 by LC remaining in the skin explants. In SHPS-1 mutant mice, we observed that the up-regulation of surface CD86 and CCR7 by LC induced by DNFB as well as that of surface CD80 and CD86 by LC in skin explants was attenuated. Finally, contact hypersensitivity (CHS) response was suppressed in SHPS-1 mutant mice and in wild-type mice treated with an anti-SHPS-1 mAb. These observations indicate that SHPS-1 plays an important role in the maturation of LC ex vivo and in vivo, and that SHPS-1-CD47 interaction may negatively regulate CHS.

Animals↗

PubMed2006

Effect of GDF-5 on ligament healing.

The effects of growth and differentiation factor-5 (GDF-5) on ligament healing were studied using a gap injury model of the medial collateral ligament in rat knee joints. The administration of GDF-5 once at the time of surgery significantly improved the mechanical properties of the femur-ligament-tibia complex. At 3 weeks after surgery, 30 microg of GDF-5 improved the ultimate tensile strength of the complex by 41%, and the stiffness by 60%, compared with the vehicle control (p < 0.05 for both; Fisher's PLSD test). The observation with a transmission electron microscopy revealed that GDF-5 increased the diameter of collagen fibrils in the repair tissue, which was considered to be a possible mechanism for the positive result in the biomechanical testing. Quantitative PCR and in situ hybridization revealed enhanced type I procollagen expression by GDF-5, and the PCR analysis also revealed that the GDF-5 treatment reduced the expression of type III procollagen relative to type I procollagen. The PCR analysis further showed that the expression of decorin and fibromodulin was relatively reduced against type I procollagen by the growth factor, which was considered to be responsible for the increase of collagen fibril diameter in the repair tissue. No adverse effects were observed, and the use of GDF-5 was considered a promising approach to facilitate ligament healing.

Animals↗

PubMed2006

Information entropy of humpback whale songs.

The structure of humpback whale (Megaptera novaeangliae) songs was examined using information theory techniques. The song is an ordered sequence of individual sound elements separated by gaps of silence. Song samples were converted into sequences of discrete symbols by both human and automated classifiers. This paper analyzes the song structure in these symbol sequences using information entropy estimators and autocorrelation estimators. Both parametric and nonparametric entropy estimators are applied to the symbol sequences representing the songs. The results provide quantitative evidence consistent with the hierarchical structure proposed for these songs by Payne and McVay [Science 173, 587-597 (1971)]. Specifically, this analysis demonstrates that: (1) There is a strong structural constraint, or syntax, in the generation of the songs, and (2) the structural constraints exhibit periodicities with periods of 6-8 and 180-400 units. This implies that no empirical Markov model is capable of representing the songs' structure. The results are robust to the choice of either human or automated song-to-symbol classifiers. In addition, the entropy estimates indicate that the maximum amount of information that could be communicated by the sequence of sounds made is less than 1 bit per second.

Acoustics↗

PubMed2005

Production of interleukin-6 and interleukin-8 by nurse-like cells from rheumatoid arthritis patients after stimulation with monocytes.

It has been reported that nurse-like cells (NLCs) play a critical role in the pathogenesis of rheumatoid arthritis (RA). The interaction between NLCs established from RA patients (RA-NLCs), and freshly isolated blood monocytes was analyzed to further elucidate the pathogenesis of RA. RA-NLC lines were established from the synovium of RA patients. The RA-NLCs were cultured with monocytes freshly isolated from peripheral blood of healthy donors, and induction of interleukin (IL)-6 and IL-8 as well as the mRNA expression of these cytokines was examined. The levels of IL-6 were over 400 times higher in the supernatant from coculture of RA-NLCs and monocytes than in those from cultures of RA-NLCs alone. Anti-tumor necrosis factor (TNF)-alpha monoclonal antibody inhibited the induction of both cytokine in a dose-dependent fashion, although there was no detectable level of TNF-alpha in the supernatant from coculture. In addition, coculture of RA-NLCs and monocytes without direct cell contact did not induce cytokine production. To determine IL-6 producing cells, RA-NLCs and monocytes were separated into each fraction after coculture for 24 h. Cocultured RA-NLCs contained approximately 80 times higher IL-6 mRNA than the RA-NLCs cultured alone. The levels of IL-8 were also much higher (about 900 times) in the supernatant from coculture than in those from cultures of RA-NLCs alone. Cocultured RA-NLCs expressed IL-8 mRNA about 620 times higher than those cultured alone. These results indicate that NLCs produce high levels of IL-6 and IL-8 after cell-cell interaction with monocytes/macrophages via membrane-bound TNF-alpha, and that activation of NLCs by monocytes/macrophages may be involved in the pathogenesis of RA through maintenance of synovial inflammation.

Journal Article↗

PubMed2004

GAD-reactive T cells were mainly detected in autoimmune-related type 1 diabetic patients with HLA DR9.

Type 1 diabetes mellitus (T1DM) is considered to be a T cell-mediated disease, and many reports suggest that some HLA types, especially HLA DR4 and DR9, convey susceptibility to T1DM in Japanese. We investigated the association between T cell reactivity against GAD and HLA types in "islet-associated autoantibody-positive" T1DM in Japanese. Blood samples were obtained from 36 "autoantibody-positive" type 1 diabetic patients with HLA DR4 or DR9 and 23 type 2 diabetic patients with HLA DR4 or DR9 as controls. They were divided into three groups, DR4/9, DR4/X, and DR9/X groups. In each HLA type group, GAD-reactive IFN-gamma-producing CD4(+) cells were assessed by means of intracellular cytokine staining for flow cytometry. Type 1 diabetic patients with HLA DR9/X had significantly higher numbers of GAD-reactive IFN-gamma-producing CD4(+) cells as compared to type 1 diabetic patients with DR4/X or DR4/9 (P < 0.05) and all type 2 diabetic patients. There was no significant difference in the number of GAD-reactive IFN-gamma-producing CD4(+) cells between type 1 diabetic and type 2 diabetic patients belonging to the DR4/X and DR4/9 groups. There was an association between T cell reactivity against GAD and HLA DR9 in Japanese type 1 diabetes.

Adult↗

PubMed2004

Evidence for existence of oligoclonal tumor-infiltrating lymphocytes and predominant production of T helper 1/T cytotoxic 1 type cytokines in gastric and colorectal tumors.

Tumor-infiltrating lymphocytes (TIL) play a central role in cellular immunity against tumor. We have revealed the characteristics of TILs in terms of T-cell receptor (TCR) repertoire, T-cell clonality, and cytokine production. TCR repertoire analyses and CDR3 size spectratyping were performed using peripheral blood mononuclear cells (PBMCs) and tissue specimens of gastric or colorectal cancers surgically resected from 11 patients. The cytokine expression was measured by real-time quantitative polymerase chain reaction. TCR repertoires were similar among multiple tissue specimens from different sites of the same tumor. Similar peak patterns of CDR3 size spectratyping were observed among these tumor specimens, but not in normal tissues or PBMCs. In addition, identical peaks were detected in multiple specimens of the same tumor. The ratio of the levels of IFN-gamma to that of IL-4 is significantly higher for tumor lesions compared with PBMCs. These results suggested that a limited number of TILs locally expand in response to tumor antigens exiting within gastric or colorectal cancers and local predominant production of the T helper 1/T cytotoxic 1 type cytokine may affect the anti-tumor immune response of TILs.

Adult↗

PubMed2003

Skew in T-cell receptor usage and clonal T-cell expansion in patients with chronic rejection of transplanted kidneys.

BACKGROUND: It is not known whether alloreactive T cells are involved in chronic rejection of transplanted kidneys. The aim of the present study was to determine the involvement of T cells in the chronic graft rejection. METHODS: T-cell receptor (TCR) variable region alpha-chain and TCR variable region beta-chain repertoires were analyzed in peripheral blood mononuclear cells. T-cell clonalities were analyzed by complementarity-determining region 3 size spectratyping. RESULTS: A significant increase in the frequencies of one or more TCR variable region alpha-chain and TCR variable region beta-chain segments was detected in 13 and 15 of the 24 kidney transplant recipients, respectively. The extent of the skew in the TCR usage was correlated with the levels of clonal T-cell expansion, indicating that the clonally expanding T cells were responsible for the skew in the TCR usage. The levels of the skew in the TCR usage and clonal T-cell expansion were significantly greater in the recipients with a graft failure than in those with a stable graft function ( P=0.0081 and P=0.012, respectively). These results indicate that the clonally expanding T cells in the periphery may be related to graft rejection. The percent increase in the serum creatinine levels, which reflected the deterioration of the kidney functions, was significantly higher in the recipients who showed high levels of clonal T-cell expansion than in those who did not ( P=0.021). CONCLUSIONS: The results demonstrate that clonal T-cell expansion in the periphery has a negative impact on the long-term graft functions, and that analysis of the clonal T-cell expansion in peripheral blood mononuclear cells provide significant information on the fate of the transplanted kidney.

Adolescent↗

PubMed2003

Adult staphylococcus scalded skin syndrome in a peritoneal dialysis patient.

Staphylococcal scalded skin syndrome (SSSS), a generalized exfoliative dermatitis complicating infections by exfoliative toxin-producing strains of Staphylococcus aureus, is rarely observed in adults, especially in those with chronic renal failure. In contrast to the mortality in infants, the mortality in adults is usually high. A case of generalized SSSS in a peritoneal dialysis patient is reported. A-62-year old Japanese man in whom peritoneal dialysis had been carried out was admitted to our hospital with acute peritonitis. It was intractable peritonitis in terms of resistance to various antibiotics; however, improvement of the peritonitis was shown after the injection of vancomycin. Nine days after the completion of this medication, erythema appeared in the eyes and mouth, and around the nostrils, with an exothermic reaction at 39.0 degrees C. Radial cracks formed in the face within a few days, and the erythema rapidly expanded to the neck, axilla, the whole body. The blood pressure was also lowered, and this led to a state of shock. Culture of skin biopsy specimens yielded identical strains of S. aureus. A presumptive diagnosis of SSSS was made. The patient was treated with antibiotics that were effective against the organisms and with both fluid supplementation and dopamine, resulting in subsidence of the signs and symptoms. The exothermic reaction and skin symptoms were improved promptly, with improvement in the general condition, including the state of shock. This appears to be the first reported case of SSSS caused by S. aureusin an adult patient with peritoneal dialysis who was treated successfully. It is very important that SSSS be differentiated from toxic epidermal necrosis, as the treatment is different.

Anti-Bacterial Agents↗

PubMed2003

Determination of T-cell receptors of clonal CD8-positive T-cells in myelodysplastic syndrome with erythroid hypoplasia.

We determined T-cell receptor alpha-chain variable (TCRAV) and T-cell receptor beta-chain variable (TCRBV) region repertoires in peripheral bloods from patients with myelodysplastic syndrome (MDS) with erythroid hypoplasia. T-cells bearing TCR ADV14S1/BV5S2, AV21S1/BV21S4, and AV2S2/BV7S2 segments were markedly increased in three of four MDS patients, respectively. In addition, there was a positive relationship between the increase in the number of CD8-positive T-cells and the expression levels of these TCR transcripts. These findings suggest that CD8-positive T-cells monoclonally or oligoclonally expanded in the peripheral blood. We also determined the nucleotide and amino acid sequences of the complementarity-determining region 3 (CDR3) of TCR alpha- and beta-chains of the expanded T-cells. Unique sequences were detected in a high percentage of the respective CDR3 clones. The gene segment of the variable and joining regions, however, varied among the patients. The deduced amino acid sequences of CDR3 were heterogeneous among the patients, and there was no common motif. These results indicate there is monoclonal or oligoclonal proliferation of CD8-positive T-cells in MDS patients with erythroid hypoplasia, and suggest that these proliferating T-cells are responsible for the pathogenesis of the MDS entity.

Aged↗

PubMed2003

T-cell function in anti-GAD65(+)diabetes with residual beta-cell function.

We have recently reported that in patients with anti-glutamic acid decarboxylase (GAD) 65(+)diabetes with residual beta-cell function, most with a 'high-titer' (>10U/ml) required insulin within 5 years, whereas most with a 'low-titer' (1.3-9.9U/ml) did not need insulin for over 15-20 years after the onset. We therefore examined T-cell function to evaluate the difference between the high-titer and low-titer groups. Interleukin (IL)-10 production upon polyclonal activation was significantly lower in the high-titer group than in the low-titer group. The serum level of interferon-inducible protein-10 (IP-10) was higher in the high-titer than the low-titer group. Although GAD65-reactive CD4(+)cells in the periphery were detected in both groups, a significant positive correlation between serum IP-10 level and the number of GAD65-reactive CD4(+)cells was observed only in the high-titer group. Therefore, it has been speculated that the co-existence of GAD65-reactive IFN-gamma-producing CD4(+)cells and a high serum IP-10 level may be important for rapid disease progression as seen in the high-titer group. Based upon these results, T-cell function is considered to be different between the high-titer and low-titer groups in anti-GAD65(+)diabetes with residual beta-cell function, supporting our previous findings regarding the clinical outcome of insulin-dependence in the two groups.

Adult↗

PubMed2003

Oral-antigen delivery via a water-in-oil emulsion system modulates the balance of the Th1/Th2 type response in oral tolerance.

PURPOSE: To evaluate the ability of a water-in-oil (W/O) emulsion containing ovalbumin (OVA), a model antigen, to induce oral tolerance and to elucidate the mechanism for the induction of oral tolerance by the emulsion system. METHODS: A W/O emulsion containing OVA was prepared and evaluated its ability to induce oral tolerance in mice. Also, the Th1/Th2 balance in the mice tolerized was investigated in terms of the ratios of anti-OVA IgG2a titer to anti-OVA IgG1 titer (IgG2a/IgG1 ratios) and cytokine profiles. RESULTS: Anti-OVA total IgG antibody titer of mice administered OVA in saline was approximately 3.5-fold higher than that of the mice administered OVA in W/O emulsion at a dose of 0.1 mg/mouse/day. Similar total IgG responses were observed between the above two at a dose of 1 mg/mouse/day. The IgG2a/IgG1 ratios decreased as the dose of OVA in W/O emulsion, but not in saline, increased at doses of 0, 0.1, and 1 mg/mouse/day. Interferon-gamma secretion of PLN cells from the mice administered OVA in W/O emulsion decreased, whereas their interleukin-4 secretion remained high. Although interferon-gamma secretion for the mice administered OVA in saline decreased, interleukin-4 secretion did not change. CONCLUSIONS: The present study suggests that oral delivery of OVA via the W/O emulsion system may more efficiently enhance the induction of Th2-dominated imbalance than that of OVA in saline.

Administration, Oral↗

PubMed2003

Assessment of beta cell mass and oxidative peritoneal exudate cells in murine type 1 diabetes using adoptive transfer system.

Because it is controversial how the beta cell mass is reduced during the disease process in type 1 diabetes, we transferred splenocytes from Non-obese diabetic (NOD) to NOD-scid mice and evaluated the relation between the status of the pancreas in donors and the time taken to transfer diabetes to the recipients. We also evaluated the usefulness of assessment of the proportion of oxidative peritoneal exudate cells (PEC) as a novel marker of disease activity in this system. We examined the proportion of oxidative PEC, pancreatic insulin content and pancreatic histology in 16-18-week-old female NOD mice (donors), and transferred their splenocytes into 5-week-old female NOD-scid mice (recipients). After the onset of diabetes in NOD-scid recipients, we assessed the relation between insulin content (or severity of insulitis) of NOD donors and the time taken to transfer diabetes to NOD-scid recipients. The insulin content of "diabetes-prone" donors whose disease status was considered to be just before the onset of diabetes ("malignant" donors) was the same as that of diabetic mice, whereas the insulin content of "diabetes-prone" donors excluding "malignant" donors ("benign" donors) was the same as that of "non-diabetes-prone" donors. Because its proportion of oxidative PEC was inversely correlated with the severity of insulitis, we then evaluated the relation between the proportion of oxidative PEC and the time taken to transfer diabetes. "Malignant" donors had less proportion of oxidative PEC (< 10%), as compared to "benign" and "non-diabetes-prone" donors. These results suggest that a marked reduction of beta cell mass occurs at the very late prediabetic stage, and assessment of the proportion of oxidative PEC is useful to evaluate disease activity in type 1 diabetes.

Adoptive Transfer↗

PubMed2003

SRCL/CL-P1 recognizes GalNAc and a carcinoma-associated antigen, Tn antigen.

SRCL /CL-P1 was recently identified as a scavenger receptor with a C-type lectin domain, which was expressed in vascular endothelial cells and could bind to Gram-positive and Gram-negative bacteria, yeast and oxidized LDL. We found that SRCL was expressed in some but not all nurse-like cells examined. Furthermore, to characterize the C-type lectin domain of SRCL, the secreted form of the C-type lectin domain (LEC-AP) of SRCL, which was fused to the signal sequence of IgG and alkaline phosphatase, was expressed in 293/EBNA-1 cells and the culture medium was used for the in vitro binding assay. LEC-AP specifically bound to GalNAc-conjugated gel in a Ca(2+)-dependent manner, and this binding was inhibited by free GalNAc, L-, D-fucose, D-galactose, lactose, and especially T antigen and Tn antigen. Furthermore, we examined whether or not SRCL could take up saccharide-conjugated particles. 293/EBNA-1 cells stably expressing SRCL were found to take up GalNAc but not mannose-conjugated particles on confocal microscopy. The binding of GalNAc-conjugated particles to these cells was quantitatively measured by comparing the x-means of individual cell populations. An approximately 2.1-fold increase in immunofluorescence intensity was observed for the SRCL transfectants compared to control vector transfectants. Our results provide a basis for understanding the scavenger function of SRCL as to carbohydrate-containing ligands.

Acetylgalactosamine↗

PubMed2003

Replacement therapy with plasma-derived factor VIII concentrates induces skew in T-cell receptor usage and clonal expansion of CD8+ T-cell in HIV-seronegative hemophilia patients.

Replacement therapy with factor VIII (FVIII) products causes immune abnormalities in human immunodeficiency virus (HIV)-seronegative hemophilia patients. However, the question remains why an absolute increase in the number of CD8+ T-cells and diminished proliferation responses of lymphocytes to antigen stimulation in vitro occurs in HIV-seronegative hemophilia patients. To examine whether the FVIII products induce skewing of T-cell receptor (TCR) repertoires, TCR variable region alpha-chain and beta-chain repertoires were analyzed for peripheral blood mononuclear cells (PBMCs) from 15 hemophilia patients treated with heated and/or non-heated plasma-derived FVIII concentrates and 10 age-matched healthy adults. Also, T-cell clonality was compared between these groups using complementarity-determining region 3 (CDR3) size spectratyping. The skewing of TCR repertoires was significantly greater for hemophilia patients than healthy controls. The extent of T-cell clonality was greater for hemophilia patients than the controls, indicating that clonal T-cells frequently expanded in hemophilia patients. The skew in TCR usage and clonal expansion were primarily observed in patients treated with non-heated plasma-derived products. The spectratyping and sequencing of CDR3 regions revealed that the clonal expansion of T-cells was observed for CD8+ T-cells, but not CD4+ T-cells. These results suggest that extensive expansion of CD8+ T-cells is induced by some viruses other than HIV present in FVIII preparations, and the resulting accumulation of CD8+ T-cells is responsible for changes in peripheral T-cell population in HIV-seronegative hemophilia patients.

Adolescent↗

PubMed2003

Relationship between beta cell mass of NOD donors and diabetes development of NOD-scid recipients in adoptive transfer system.

BACKGROUND: There is controversy about the way the beta cell mass is reduced in type 1 diabetes. One view is that a gradual fall in beta cell mass begins soon after the onset of insulitis. Another view is that a sudden wave of beta cell destruction occurs just before the onset of diabetes. To clarify how the beta cell mass is reduced, we performed adoptive transfer experiments and examined the relationship between the pancreatic status of NOD donors and the time taken to transfer diabetes into NOD-scid recipients. METHODS: We killed 18-week-old female NOD mice (n = 20), removed their spleen, and transferred splenocytes into 5-week-old female NOD-scid mice (n = 60). The relationship between the pancreatic status of donors and the time taken to transfer diabetes into recipients was assessed. As pancreatic status, we measured insulin content and severity of insulitis. RESULTS: There was no linear correlation between the pancreatic status of donors and the time taken to transfer diabetes into recipients. NOD donors who needed 7 or more weeks to transfer diabetes in NOD-scid recipients had similar levels of insulin content or severity of insulitis as those of NOD donors who could not transfer diabetes. On the other hand, NOD donors who needed 6 or less weeks to transfer diabetes in recipients had similar levels of insulin content or severity of insulitis as those of diabetic NOD mice. CONCLUSIONS: According to our observations, beta cell mass seems to be preserved until just before the onset of diabetes and decreased dramatically within a few weeks.

Adoptive Transfer↗