PubMed Health⌕ Search

Biomedical subjects

T Mohanakumar

Publications and source records attributed to T Mohanakumar.

At least 91 records · Page 5Linked to original sources
PubMed2001

Increased expression of HDJ-2 (hsp40) in carotid artery atherosclerosis: a novel heat shock protein associated with luminal stenosis and plaque ulceration.

PURPOSE: Evidence suggests that both humoral and cellular autoimmune processes directed toward heat shock proteins (hsp) contribute to the pathogenesis of atherosclerosis. We characterized a human hsp distinct from those previously characterized in atherosclerotic lesions, termed HDJ-2. METHODS: To determine the role of HDJ-2 in atherosclerosis, we compared the level of HDJ-2 mRNA expression with the level of hsp60 and hsp70 mRNA expression in 26 carotid endarterectomy specimens and 17 normal arteries. The level of expression of HDJ-2 mRNA was also correlated to the presence of plaque ulceration and the degree of luminal stenosis associated with the lesion. RESULTS: The expression of HDJ-2 and hsp70 was significantly higher in carotid artery plaques as compared with normal arteries: HDJ-2, 6.7 +/- 1.6 vs 0.1 +/- 0.04, (P =.001); hsp70, 9.5 +/- 0.9 vs 3.7 +/- 0.8, (P =.002). There was no significant difference in hsp60 expression between carotid artery plaques and normal arteries (21.0 +/- 0.9 vs 20.6 +/- 0.8, P =.65). Increased HDJ-2 expression in carotid artery plaques was independent of hsp70 (Pearson correlation, r = 0.11; Bartlett chi(2) analysis, P =.71). Within the ulcerated plaque group, there was a correlation between degree of stenosis and high HDJ-2 mRNA expression (r = 0.896, P =.016). However, there was no correlation between degree of stenosis and high HDJ-2 mRNA expression within the nonulcerated plaque group (r = 0.530, P =.076) or within the entire group of patients (r = 0.0085, P =.97). CONCLUSION: These results demonstrate that expression of HDJ-2 is significantly increased in atherosclerotic carotid artery plaques as compared with hsp60 and hsp70 and correlates with luminal stenosis in ulcerated atherosclerotic carotid artery plaques.

Arteriosclerosis↗
PubMed2001

Lung transplantation and bronchiolitis obliterans: an evolution in understanding.

Major advancements in the field of lung transplantation have occurred over the past thirty-five years. Despite these advancements, limitations in our ability to obtain sufficient numbers of organs and in our comprehension of the problems associated with the procedure persist. The purpose of this article is to review the current understanding of both the surgical procedure and its most unfortunate complication, bronchiolitis obliterans. Even now, after over three decades of experience, this complication remains the most significant cause of morbidity and mortality following lung transplantation. This article is not meant to be an exhaustive review, and certainly there are important topics not covered herein. We have focused the discussion on ongoing studies, which attempt to understand bronchiolitis obliterans at both the clinical as well as the immunopathological level.

Animals↗
PubMed2001

The Barnes-Jewish Hospital/Washington University Renal Transplant Program: comparison of two eras 1991-1994 and 1995-2000.

The first cadaveric transplant at Barnes-Jewish Hospital/Washington University was performed in 1963, the first living related transplant in 1965, and the first living unrelated transplant in 1983. Changes in the renal transplant program initiated in 1993 and 1994 resulted in many improvements over the past decade. Our comparison of 2 modern eras of transplant, 1991-1994 and 1995-2000, showed the following: 1. No significant differences in patient and donor characteristics. 2. Trends toward greater use of living donors (p = 0.07), older cadaveric donors (p = 0.084) and particularly cadaveric donors > 55 years of age (p = 0.09). 3. Decreasing mean CIT: 19.2 hours vs. 14.2 hours (p < 0.001). 4. Decreasing use of donors with CIT > 24 hours: 22% to 3%, (p < 0.001). 5. Decreased rate of DGF: 13% vs. 8% (p = 0.044). 6. Decreased rate of symptomatic CMV: 35% vs. 14% (p < 0.001). 7. Decreased rate of PTLD: 3.5% vs. 0.5% (p = 0.004). 8. Decreased one-year rate of acute rejection: 41% vs. 15% (p < 0.001). 9. Current one-year rate of acute rejection < 8%. 10. Decreased length of initial hospital stay: 12.7 days to 8.0 days (p < 0.001). 11. Decreased length of hospital in the first year after transplant: 10.6 days vs. 6.4 days (p < 0.001). 12. There were no improvements in patient and graft survival at one and 3 years. a. one-year patient survival rates: 95% vs. 96%. b. 3-year patient survival rates: 90% vs. 90%. c. one-year death-censored graft survival rates: 91% vs. 94%. d. 3-year death-censored graft survival rates: 87% vs. 88%.

Academic Medical Centers↗
PubMed2000

Clotrimazole inhibits lung fibroblast proliferation in vitro: implications for use in the prevention and treatment of obliterative bronchiolitis after lung transplantation.

BACKGROUND: Immunosuppressive therapy has limited activity against the mesenchymal cell proliferation of obliterative bronchiolitis. Clotrimazole (CLT) has been shown to inhibit proliferation in normal and cancer cell lines. Here we investigate whether CLT inhibits the proliferation of lung mesenchymal cells. METHODS: Proliferation of human lung fibroblasts (MRC-5) in the presence of CLT was determined by [3H]thymidine incorporation. Messenger ribonucleic acid (mRNA) expression of platelet-derived growth factor (PDGF)-B and transforming growth factor (TGF)-beta after treatment with CLT was measured by reverse transcriptase-polymerase chain reaction. RESULTS: Treatment of MRC-5 cells with CLT resulted in a significant reduction in proliferation as assessed by DNA incorporation and cell counts compared with dimethylsulfoxide alone. There was no cytotoxic effect associated with CLT treatment. Reverse transcriptase-polymerase chain reaction demonstrated a marked decrease in PDGF-B and TGF-beta mRNA levels in cells treated with CLT compared with those treated with dimethylsulfoxide. CONCLUSION: CLT inhibits proliferation of human lung fibroblasts. This inhibitory effect is associated with decreased levels of PDGF-B and TGF-beta mRNA expression and may have value in the prevention and treatment of obliterative bronchiolitis.

Bronchiolitis Obliterans↗
PubMed2000

The economic benefit of allocation of kidneys based on cross-reactive group matching.

BACKGROUND: Recently the United Network for Organ Sharing (UNOS) began a pilot study to evaluate prospectively the merits of an allocation of cadaveric kidneys based on broader classes of HLA antigens, called cross-reactive groups (CREG). The objectives of the pilot study consider patient outcomes, but not the potential economic impact of a CREG-based allocation. This study predicts the impact of a CREG-based local allocation of cadaveric kidneys on 3-year Medicare payments and graft survival. METHODS: The UNOS renal transplant registry was merged to Medicare claims data for 1991-1997 by the United States Renal Data System. Average accumulated Medicare payments and graft survival up to 3 years posttransplant for first cadaveric renal transplant recipients were stratified by cross-reactive group mismatch categories. The economic impact was defined as the difference in average 3-year costs per transplant between the current and proposed allocation algorithms. Average 3-year costs were computed as a weighted average of costs, where the weights were the actual and predicted distributions of transplants across cross-reactive group categories. RESULTS: Results suggest that an organ allocation based on cross-reactive group matching criteria would result in a 3-year cost savings of $1,231 (2%) per transplant, and an average 3-year graft survival improvement of 0.6%. CONCLUSIONS: Cost savings and graft survival improvements can be expected if CREG criteria were to replace current criteria in the current allocation policy for cadaveric kidneys, although the savings appear to be smaller than may be achievable through expanded HLA matching.

Algorithms↗
PubMed2000

Indirect recognition of porcine swine leukocyte Ag class I molecules expressed on islets by human CD4+ T lymphocytes.

Xenotransplantation of porcine islets is considered a viable alternative treatment for type 1 diabetes mellitus. Therefore, we characterized human PBL responding to porcine islets both in vitro by coculture and in vivo using SCID mice reconstituted with human PBLs (HuPBL-SCID) and transplanted with porcine islets. T cell lines generated in vitro and graft-infiltrating T cells obtained from HuPBL-SCID mice were CD4+-proliferated specifically to porcine islets cultured with autologous APC. This proliferation was abrogated by an anti-human class II Ab. These T cell lines also proliferated to purified swine leukocyte Ag (SLA) class I molecules in the presence of self-APC, indicating that the primary xenoantigens recognized are peptides derived from SLA. This CD4+ T cell line lysed porcine islets but not splenocytes. CD4+ T cell clones with Th0, Th1, and Th2 cytokine profiles were isolated. The Th0 and Th1 clones lysed porcine islets, whereas the Th2 clone that secreted a large amount of IL-4 was not lytic. These results demonstrate that human T cells responding to porcine islets are primarily CD4+ and recognize porcine xenoantigens by the indirect Ag pathway presentation. These activated T cells produce cytokines that lyse islets. Furthermore, we demonstrate that the major porcine xenoantigens recognized are SLA class I molecules.

Animals↗
PubMed2000

Chimerism in peripheral blood of sensitized patients waiting for renal transplantation: clinical implications.

BACKGROUND: Potential renal transplant recipients with preformed antibodies to HLA resulting from previous transplants, pregnancy, and/or transfusions are unlikely to receive an allograft. The factors contributing to the long-term maintenance of antibody titers in these individuals are still unknown. In the present study, we sought to determine whether chimerism in the blood correlates with maintenance of HLA sensitization in highly sensitized patients. METHODS: Qualitative analysis of chimerism in blood of sensitized patients was assessed by polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP) to HLA-DR. PCR single-strand conformation polymorphism (PCR-SSCP) was used to confirm the extra HLA-DR antigens detected by PCR-SSOP. RESULTS: Fourteen of 36 patients (38.9%) were positive for more than two HLA-DR indicative of chimerism. The presence of extra HLA-DR was confirmed by PCR-SSCP. When patients were analyzed on the basis of their panel-reactive antibody (PRA) status, 10 of 15 (66.7%) were positive for chimerism in the sensitized group, compared with only two of eight (25%) in the unsensitized group. Of the five males in the sensitized group who had received a blood transfusion but not a transplant, three were positive for chimerism. An association was observed between chimerism and maintenance of sensitization. None of the eight normal subjects studied demonstrated chimerism. CONCLUSIONS: The results obtained with sensitized patients suggest an association between blood chimerism and maintenance of HLA sensitization. We speculate that chimerism may lead to long-term maintenance of anti-HLA antibody titers. This finding implies that abolition of chimerism could result in the eventual elimination of antigenic stimuli for antibody production against HLA antigens.

Antibodies↗
PubMed2000

Brief cyclosporine treatment prevents intrathymic (IT) tolerance induction and precipitates acute rejection in an IT rat cardiac allograft model.

BACKGROUND: Intrathymic (IT) alloantigen combined with administration of rabbit anti-rat anti-lymphocyte serum (ALS) intraperitoneally induces donor-specific tolerance to rat cardiac transplants. The purpose of this study was to examine the effect of a brief course (4 days) of cyclosporine (CsA) on the development of IT tolerance. METHODS: Buffalo (BUF) (RT1b) rats were given 25x10(6) fully MHC-mismatched Lewis (LEW) (RT1l) splenocytes by IT injection plus 1.0 ml of ALS intraperitoneally. Twenty-one days later, IT donor-specific LEW (group 1) or third-party (ACI, RT1a) (group 2) hearts were heterotopically transplanted to the abdominal aorta A third group of BUF (group 3) were given daily CsA (10 mg/kg) by oral gavage for 4 days before administration of IT LEW cells and ALS. Rejection as defined by the cessation of a palpable heartbeat was confirmed by histology. Cytokine profiles of allografts from all groups were then analyzed using a multi-probe RNase protection assay. RESULTS: Sixty-seven percent of IT/ALS-treated BUF recipients not pretreated with CsA accepted LEW heart grafts for greater than 90 days. However, 86% of animals treated with CsA for 4 days before IT injection and ALS rejected allografts at 10.7+/-3.2 days. Third-party allografts (ACI) were uniformly rejected (7.0+/-0.0 days). Histology confirmed cellular rejection in CsA-treated allografts and cytokine analysis detected increased interleukin (IL)-3, IL-5, and tumor necrosis factor-alpha when compared to increased IL-2 and interferon-gamma in rejecting untreated controls. CONCLUSIONS: CsA can prevent the induction of intrathymic alloantigen tolerance. These results support the development of a CsA-sensitive, but IL-2-independent, active regulatory mechanism after intrathymic exposure to donor-specific alloantigen and depletion of mature peripheral T cells.

Animals↗
PubMed2000

Liver transplant recipient sera derived soluble HLA mediates allele specific CTL apoptosis.

BACKGROUND: Significant levels of donor soluble human leukocyte antigen (HLA) class I (sHLA) are present in patients after transplants. We investigated the possibility that sHLA may inhibit cytolytic T lymphocyte (CTL) activity by inducing apoptosis of the CTL, thereby serving as a mechanism for specific tolerance. METHODS: sHLA-A2 and A3 were isolated from the sera of liver transplant recipients by affinity chromatography. T cell bulk lines directed against HLA-A2 and HLA-A3 were generated by stimulation with HLA-A2, A3+ peripheral blood leukocytes and B-lymphoblastoid cells. Induction of T cell apoptosis by sHLA was analyzed by adding sHLA to allospecific CTL 4 or for 24 hr before flow cytometric analysis of propidium iodide and fluorescein isothiocyanate-conjugated annexin V stained cells. T cell receptor (TCR) engagement by sHLA was demonstrated using a monoclonal antibody specific for the TCR. RESULTS: sHLA-A3 inhibited CTL activity of a HLA-A3 T cell line by 53%, whereas sHLA-A2 had no effect. sHLA-A3 also increased T cell death by 77% over the control, whereas sHLA-A2 had no significant effect. However, sHLA-A2 induced 21% apoptosis of an anti-HLA-A2 T cell line, whereas sHLA-A3 caused only 3% apoptosis. The antibody complexed form of sHLA was ineffective in the induction of apoptosis. Preincubation of the T cells with anti-T cell receptor monoclonal antibody protected the T cells from sHLA-induced apoptosis, indicating that sHLA-TCR engagement is necessary for this process to occur. CONCLUSION: TCR-mediated apoptosis of alloreactive CTL may serve as a mechanism by which sHLA can modulate the immune response.

Alleles↗
PubMed2000

In vivo adenovirus-mediated endothelial nitric oxide synthase gene transfer ameliorates lung allograft ischemia-reperfusion injury.

OBJECTIVE: Nitric oxide regulates vascular tone, inhibits platelet aggregation, and inhibits leukocyte adhesion, all of which are important modulators of ischemia-reperfusion injury. This study aimed to determine the effects of endothelial constitutive nitric oxide synthase gene transfer on ischemia-reperfusion injury in a rat lung transplant model. METHODS: In group I, donor animals were injected intravenously with 5 x 10(9) pfu of adenovirus-encoding endothelial constitutive nitric oxide synthase. Groups II and III served as controls, whereby donor animals were injected with either 5 x 10(9) pfu of adenovirus encoding beta-galactosidase or saline solution, respectively. Twenty-four hours after injection, left lungs were harvested and preserved for 18 hours at 4 degrees C, then implanted into isogeneic recipients, which were put to death 24 hours later. Recombinant endothelial constitutive nitric oxide synthase gene expression was evaluated by Western blotting and immunohistochemistry. Lung grafts were assessed by measuring arterial oxygenation, myeloperoxidase activity, and wet/dry weight ratios. RESULTS: Western blotting confirmed the overexpression of endothelial constitutive nitric oxide synthase in lungs so transfected compared with controls. Twenty-four hours after reperfusion, mean arterial oxygenation was significantly improved in group I compared with group II and III controls (189.4 +/- 47.1 mm Hg vs 71.7 +/- 8.9 mm Hg and 67.8 +/- 12.2 mm Hg, P =.02, P =.01, respectively). Myeloperoxidase activity, a reflection of tissue neutrophil sequestration, was also significantly reduced in group I compared with groups II and III (0.136 +/- 0.038 DeltaOD/mg/min vs 0. 587 +/- 0.077 and 0.489 +/- 0.126 DeltaOD/mg/min, P =.001, P =.01, respectively). CONCLUSION: Adenovirus-mediated gene transfer with endothelial constitutive nitric oxide synthase ameliorates ischemia-reperfusion injury as manifested by significantly improved oxygenation and decreased neutrophil sequestration in transplanted lung isografts. Endothelial constitutive nitric oxide synthase gene transfer may reduce acute lung dysfunction after lung transplantation.

Adenoviridae↗
PubMed2000

Anti-HLA antibody binding to hla class I molecules induces proliferation of airway epithelial cells: a potential mechanism for bronchiolitis obliterans syndrome.

OBJECTIVE: Development of anti-HLA antibodies is associated with development of bronchiolitis obliterans syndrome after lung transplantation. We sought to determine the mechanism by which anti-HLA antibodies affect the development of bronchiolitis obliterans syndrome. We postulated that anti-HLA antibodies bind to the donor lung epithelium and stimulate phosphorylation and proliferation. METHODS: The A549 lung epithelial carcinoma cell line was cultured in serum-deficient medium to produce static growth. Then the cells were treated with anti-HLA sera from lung transplant recipients, pooled anti-HLA serum from highly sensitized patients, or normal human serum. The cells were also treated with the W6/32 mouse anti-HLA class I monoclonal antibody or control mouse IgG. Tritiated thymidine uptake was determined at 24, 48, and 72 hours. In parallel experiments the cells were treated as described above, and the levels of tyrosine phosphorylation were determined by Western blot analysis. RESULTS: Cells treated with anti-HLA serum or the W6/32 monoclonal antibody exhibited significantly greater proliferation and tyrosine phosphorylation of proteins of approximately 170, 130, 110, and 70 kd compared with cells treated with normal human serum or mouse IgG, respectively. CONCLUSIONS: These data indicate that anti-HLA antibodies have the ability to stimulate airway epithelial cell proliferation and that they may play an important role in the development of bronchiolitis obliterans syndrome. Prevention of HLA sensitization and immunosuppression with agents capable of blocking indirect antigen presentation and the humoral immune response against the allograft may be pivotal in preventing the development of bronchiolitis obliterans syndrome after lung transplantation.

Antibodies, Monoclonal↗
PubMed2000

Airway epithelial cell damage mediated by antigen-specific T cells: implications in lung allograft rejection.

The aim of this study is to assess the mechanisms associated with airway epithelial cell (AEC) injury, which may have implications in lung allograft rejection. Three AEC lines, KDI-650, Beas-2B and A549 were analyzed. Effect of cytokines on the expression of Fas, HLA class I, and HLA class II were assessed by flow cytometry. AEC-specific T cells were generated in vitro and assessed for lysis by (51)Cr release assay. HLA class I and Fas were expressed on all AEC lines. Beas-2B and A549 expressed low levels of class II compared with KDI-650, which lack this expression. Expression of HLA class II was augmented on KDI-650 and Beas-2B by IFN-gamma treatment. AEC-specific T cells generated in vitro were predominantly CD8(+) and lysed relevant AEC targets. Anti-HLA class I monoclonal antibodies inhibited the lysis of AEC by specific T cells while anti-Fas and anti-HLA class II monoclonal antibodies did not have any effect on the T cell induced lysis of AECs. AECs cultured with supernatant derived from T-cell cultures induced the expression of Fas, HLA class I, as well as HLA class II. These results suggest AEC damage is mediated by AEC-specific T cells primarily by the conventional HLA class I/peptide complex and TCR interaction. Further, the factors released by these T cells also induce the expression of Fas, as well as HLA class I and class II, which may have implications on the outcome of the immune response against AECs.

Antibodies, Monoclonal↗
PubMed2000

Increased expression of inflammatory cytokines and adhesion molecules by alveolar macrophages of human lung allograft recipients with acute rejection: decline with resolution of rejection.

BACKGROUND: Alveolar macrophages (AM) are the major population in bronchoalveolar lavage (BAL) cells; we assessed their role in human lung allograft recipients by correlating the expression of adhesion molecules and inflammatory cytokines with clinical outcome of allograft. METHODS: We obtained BAL samples from patients and enriched them for AM in plastic petri dish for 2 hours at 37 degrees C in 5% CO(2). Expression of intercellular adhesion molecule-1 (ICAM-1, CD54), platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31), and CD11c was assessed by flow cytometry using monoclonal antibodies. We assessed cytokine profile using Multi-Probe RNase protection assay. RESULTS: Alveolar macrophages that express CD11c, CD31 and CD54 were increased in patients with either rejection or infection compared with those without rejection and infection. The difference in the percentage of AM expressing CD11c and CD31 between the rejection group and patients without rejection and infection group was statistically significant (CD11c, p < 0.01; CD31, p < 0.03). Interleukin (IL)-1 alpha, IL-1 beta, IL-1 receptor antagonist (IL-1Ra), and IL-6 expression was higher in the rejection group than in patients without rejection. Five out of 9 patients in the rejection group expressed high levels of IL-15 and tumor necrosis factor-alpha compared with patients without rejection and infection. The increased number of AM expressing adhesion molecules and elevated expression of cytokines observed during acute rejection declined to basal levels after successful treatment and resolution of rejection. This study demonstrates that lung allograft rejection is associated with increased expression of adhesion molecules and inflammatory cytokines by AM, which could facilitate mononuclear cell adhesion and extravasation contributing to the allograft injury in lung transplant recipients.

Bronchoalveolar Lavage Fluid↗
PubMed2000

Cytomegalovirus immune globulin intravenous (human) administration modulates immune response to alloantigens in sensitized renal transplant candidates.

One of the important parameters for prolonged waiting time for potential renal transplant recipients is the presence of preformed antibodies to human leucocyte antigen (HLA) antigens, which is often caused by previous transplants, pregnancy or transfusions. In vivo administration of specific and unselected polyclonal intravenous immunoglobulin (IVIGs) preparations have been shown to inhibit anti-HLA alloantibodies in highly sensitized patients. We sought to determine whether Cytogam (Medimmune Inc., Gaithersburg, MD, USA), a hyperimmune anticytomegalovirus immunoglobulin would (1) effect either in vitro or in vivo alloreactivity, and (2) whether Cytogam therapy could reduce the titre of preformed anti-HLA antibodies in highly sensitized patients. Alloreactivity was assessed by mixed lymphocyte reaction (MLR) and cytotoxic T lymphocyte (CTL) assay. A complement dependent microlymphocytotoxicity assay was done to assess for panel reactive antibody (PRA) status and the presence of anti-idiotypic antibodies in the Cytogam preparation. The MLR was inhibited by Cytogam in vitro in a dose-dependent fashion ranging from 31-92%. Significant inhibition of the MLR responses was not observed in recipients who received Cytogam in vivo (50 mg/kg). This could be a result of adminstration of a low dose of IVIG. However, CTL activity against the alloantigens in all individuals assessed was significantly inhibited after in vivo administration of Cytogam. Three of five individuals experienced a decrease of 5-32% in the PRA status at 4 weeks post administration of Cytogam. Cytogam also blocked the anti-HLA antibody titres in a microlymphocytotoxicity assay, suggesting the presence of anti-idiotypic antibodies. Our study was based on a single prophylactic dose of Cytogam (50 mg/kg), however, higher dose administration could be feasible by removing more fluid at dialysis, but should be given intradialytically to avoid volume overload. Overall, our results suggest that Cytogam can modulate the in vivo and in vitro T cell responses against the alloantigens.

Adult↗
PubMed2000

Evidence for cytotoxic T lymphocyte response against human lung cancer: reconstitution of antigenic epitope with peptide eluted from lung adenocarcinoma MHC class I.

BACKGROUND: Cancer-associated, major histocompatibility complex (MHC)-restricted peptide antigens have been elucidated in human melanomas and ovarian, breast, and renal carcinomas; but relatively little is known about lung cancer antigens. METHODS: To work toward delineation of lung cancer-associated antigens, we developed tumor infiltrating lymphocytes (TILs), peripheral blood mononuclear cell-derived cytolytic T cell lines (CTL), autologous lung cancer cell lines, and normal lung cell lines from 17 patients undergoing lung cancer resections. The TILs and CTL lines were subsequently evaluated for markers of activation and specific lysis of autologous or allogeneic lung cancer cell lines or both. RESULTS: Freshly isolated TILs contained a more activated T cell population compared with the patients' peripheral blood T cells as evidenced by an increased expression of HLA-DR, CD25, and CD45RO. TILs isolated from 15 patients lysed allogeneic lung cancer lines. TILs lysed autologous lung cancer but not autologous normal lung or Epstein-Barr virus transformed B cell lines (B-LCL) in 4 of 8 cases tested, suggesting tumor specificity. A CTL line (RHPBL57.1) was generated from peripheral blood mononuclear cells of an HLA-A24(+) patient by stimulation against an established HLA-A24(+) allogeneic lung cancer cell line. RHPBL57.1 lysed the lung cancer cell line in an HLA-A24-restricted manner. Moreover, RHPBL57.1 specifically lysed autologous B-LCL pulsed with peptides, eluted from MHC class I and isolated from the HLA-A24(+) lung cancer cell line. CONCLUSIONS: TILs isolated from patients with lung cancer are predominantly an activated population of T cells with evidence of tumor and MHC class I-restricted lysis. Furthermore, we provide evidence for a lung cancer-associated, MHC class I-bound peptide antigen(s) that reconstitutes the epitope recognized by a lung cancer specific CD8(+) T cell line derived from a patient with lung cancer.

Adenocarcinoma↗
PubMed2000

Adenovirus-mediated gene transfer of human interleukin 10 ameliorates reperfusion injury of rat lung isografts.

OBJECTIVE: The objective of this study was to examine the feasibility of human interleukin 10 gene transfer into rat lung isografts and to investigate the effect of gene transfer on subsequent ischemia-reperfusion injury. METHODS: Male F344 rats were divided into 4 groups and underwent left lung isotransplantation. Twenty-four hours before harvest, 5 x 10E9 pfu (group I, n = 6) or 1 x 10E10 pfu (group II, n = 7) of AdRSVhIL-10 was intravenously administered to donor rats. In group I-C (n = 6) and group II-C (n = 6), serving as controls, 5 x 10E9 pfu and 1 x 10E10 pfu of AdCMVLacZ were administered, respectively. Grafts were preserved for 18 hours at 4 degrees C before implantation and assessed 24 hours after reperfusion. Transgene expression of human interleukin 10 was assessed by both reverse transcriptase-polymerase chain reaction and immunohistochemistry. Graft inducible nitric oxide synthase, tumor necrosis factor alpha, intercellular adhesion molecule-1, growth-regulated gene product/cytokine-induced neutrophil chemoattractant-1, and monocyte chemotactic protein-1 mRNA expression were assessed by reverse transcriptase-polymerase chain reaction. Isograft gas exchange, exhaled nitric oxide, and myeloperoxidase activity were also analyzed. RESULTS: Dose-dependent transgene expression was detected by reverse transcriptase-polymerase chain reaction and immunohistochemistry. Arterial PO (2) in groups I (164.72 +/- 85.3 mm Hg) and II (153.19 +/- 113 mm Hg) was significantly higher than in groups I-C (82.37 +/- 19.1 mm Hg) and II-C (77.95 +/- 33.4 mm Hg) (P =.022 and P =.031, respectively). Arterial PCO (2) in group I (33.40 +/- 6.80 mm Hg) was significantly lower than in group I-C (51.23 +/- 11.9 mm Hg) (P =.0096). Myeloperoxidase activity in group II (0.083 +/- 0.031 DeltaOD. min(-1). mg(-1)) was significantly lower than in group II-C (0.117 +/- 0.028 DeltaOD. min(-1). mg(-1)) (P =.044). The inducible nitric oxide synthase mRNA expression in group II (0.627 +/- 0.28) was significantly lower than in group II-C (1.125 +/- 0.63) (P =. 039). CONCLUSION: Adenovirus-mediated human interleukin 10 gene transfer in vivo into lung isografts ameliorates subsequent ischemia-reperfusion injury. This results in improved graft gas exchange, reduced neutrophil sequestration, and down-regulation of graft inducible nitric oxide synthase mRNA expression.

Adenoviridae↗
PubMed1999

HLA-E and HLA-G expression on porcine endothelial cells inhibit xenoreactive human NK cells through CD94/NKG2-dependent and -independent pathways.

Human NK cells contribute a significant role to host defense as well as xenogeneic cytotoxicity. Previous studies using human 721.221 cell line have shown that peptides derived from the leader sequence of the HLA-G binds and up-regulates the surface expression of HLA-E molecules, which was considered to consequently provide negative signals to human NK cells. However, the direct role of HLA-G in inhibiting human NK cells remains controversial. In this study, we showed that the expression of HLA-G or HLA-E in porcine endothelial cells directly protected sensitive porcine cells from human NK cell-mediated xenogeneic cytotoxicity. Ab blocking assays using F(ab')2 of the HLA class I-specific mAb PA2.6 indicated that the protection was directly mediated by the expression of HLA-G and HLA-E on the porcine cells. The HLA-E-mediated protection was blocked by anti-human CD94 Ab. In addition, the engagement of HLA-E lead to the phosphorylation of the CD94/NKG2 complex and the recruitment of SH2 domain-containing protein phosphatase 1 (SHP-1) to the complex. Therefore, HLA-E protected porcine cells from xenoreactive human NK cells through a CD94/NKG2-dependent pathway. In contrast, HLA-G inhibited human NK cells in the absence of CD94/NKG2 phosphorylation or SHP-1 recruitment, and the inhibition was not blocked by anti-CD94 Ab. Therefore, HLA-G protected porcine cells from human NK cells through a CD94/NKG2-independent pathway. These results demonstrated that both HLA-E and HLA-G could directly inhibit human NK cells in the absence of other endogenous HLA class I molecules. These results also have practical implications in preventing xenograft rejection mediated by human NK cells.

Animals↗