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2.
Pediatr Transplant ; 17(6): 582-8, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23802616

ABSTRACT

We report a retrospective analysis of 53 haematopoietic stem cell transplants for inherited metabolic disorders performed at ANZCHOG transplant centres between 1992 and 2008. Indications for transplant included Hurler syndrome, ALD, and MLD. The majority of transplants utilized unrelated donor stem cells (66%) with 65% of those being unrelated cord blood. Conditioning therapy was largely myeloablative, with Bu plus another cytotoxic agent used in 89% of recipients. Primary graft failure was rare, occurring in three patients, all of whom remain long-term survivors following the second transplant. The CI of grade II-IV and grade III-IV acute GVHD at day +100 was 39% and 14%, respectively. Chronic GVHD occurred in 17% of recipients. TRM was 12% at day +100 and 19% at one yr post-transplant. OS at five yr was 78% for the cohort, 73% for patients with ALD and 83% for patients with Hurler syndrome. There was no statistically significant difference in overall survival between unrelated marrow and unrelated cord blood donor groups. The development of interstitial pneumonitis was an independent variable shown to significantly impact on TRM and OS. In summary, we report a large cohort of patients with inherited metabolic disorders with excellent survival post-allogeneic transplant.


Subject(s)
Bone Marrow Transplantation/methods , Hematopoietic Stem Cell Transplantation/methods , Metabolism, Inborn Errors/therapy , Adrenoleukodystrophy/therapy , Australia , Cohort Studies , Female , Graft vs Host Disease , Humans , Leukodystrophy, Metachromatic/therapy , Male , Mucopolysaccharidosis I/therapy , Multivariate Analysis , New Zealand , Registries , Retrospective Studies , Transplantation Conditioning/methods , Treatment Outcome
3.
Bone Marrow Transplant ; 43(3): 207-15, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18806837

ABSTRACT

Unrelated umbilical cord blood (UCB) is an alternative stem cell source for paediatric patients lacking a matched related or unrelated marrow donor. We report the results of all paediatric unrelated UCB transplants performed in Australia and New Zealand over a 10-year period. A total of 135 patients were transplanted, 100 for malignant disease (74%) and 35 for non-malignant disorders. The majority (88%) of patients received an HLA-mismatched graft. The median infused total nucleated cell dose was 4.7 x 10(7)/kg and CD34+ count 1.9 x 10(5)/kg. Neutrophil engraftment occurred in 83% of patients by day 42 (median 23 days) and platelet engraftment in 55% by day 60 (median 56 days). Grades II-IV and III-IV acute GVHD occurred in 41 and 18% of patients, respectively. TRM and overall survival 1-year post transplant were 32 and 61%, respectively. A higher probability of neutrophil recovery (P=0.004) and faster time to recovery (median 18 days vs 26 days, P=0.008) were observed in recipients of a cord unit with a CD34 cell dose >or=1.7 x 10(5)/kg. Our results support selection of cord units with CD34 cell doses >or=1.7 x 10(5)/kg to promote faster engraftment, improve survival and lower TRM.


Subject(s)
Cord Blood Stem Cell Transplantation , Fetal Blood/transplantation , Hematologic Diseases/therapy , Antigens, CD34/blood , Antigens, CD34/immunology , Child , Child, Preschool , Fetal Blood/immunology , Graft vs Host Disease/immunology , Hematologic Diseases/prevention & control , Hematopoiesis , Humans , Neutrophils/immunology , Neutrophils/transplantation , Regression Analysis , Retrospective Studies , Survival Rate , Treatment Outcome
4.
Tissue Antigens ; 69 Suppl 1: 15-6, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17445156

ABSTRACT

Good communication between the bone marrow registries, the donor centres, tissue typing laboratories and clinical units is paramount to ensure timely identification, testing and selection of donors for unrelated bone marrow transplants. This panel session focussed on how to improve communication so that there was a clear understanding of prioritization of requests from clinicians, typing strategies in the laboratories and requests for donors to the registries. This paper outlined some of the strategies discussed in this session.


Subject(s)
Histocompatibility Testing , Interdisciplinary Communication , Laboratories/organization & administration , Tissue and Organ Procurement/organization & administration , Transplants , Humans , Interprofessional Relations , Registries , Tissue Donors
5.
J Med Genet ; 43(10): 769-87, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16571647

ABSTRACT

Marfan syndrome (MFS), a relatively common autosomal dominant hereditary disorder of connective tissue with prominent manifestations in the skeletal, ocular, and cardiovascular systems, is caused by mutations in the gene for fibrillin-1 (FBN1). The leading cause of premature death in untreated individuals with MFS is acute aortic dissection, which often follows a period of progressive dilatation of the ascending aorta. Recent research on the molecular physiology of fibrillin and the pathophysiology of MFS and related disorders has changed our understanding of this disorder by demonstrating changes in growth factor signalling and in matrix-cell interactions. The purpose of this review is to provide a comprehensive overview of recent advances in the molecular biology of fibrillin and fibrillin-rich microfibrils. Mutations in FBN1 and other genes found in MFS and related disorders will be discussed, and novel concepts concerning the complex and multiple mechanisms of the pathogenesis of MFS will be explained.


Subject(s)
Marfan Syndrome/genetics , Activin Receptors, Type I/genetics , Aortic Dissection/genetics , Animals , Aortic Aneurysm, Thoracic/genetics , Contractile Proteins/physiology , Databases, Genetic , Extracellular Matrix Proteins/physiology , Fibrillin-1 , Fibrillins , Humans , Latent TGF-beta Binding Proteins/genetics , Marfan Syndrome/complications , Mice , Microfibrils/metabolism , Microfilament Proteins/genetics , Models, Animal , Models, Biological , Protein Denaturation/genetics , Protein Serine-Threonine Kinases , RNA Splicing Factors , Receptor, Transforming Growth Factor-beta Type I , Receptor, Transforming Growth Factor-beta Type II , Receptors, Transforming Growth Factor beta/genetics
6.
Br J Cancer ; 94(7): 1007-10, 2006 Apr 10.
Article in English | MEDLINE | ID: mdl-16570049

ABSTRACT

Ovarian cryopreservation is a promising technique to preserve fertility in women with Hodgkin lymphoma (HL) treated with chemotherapy. Thus, the aim of this study was to examine harvested ovarian tissue for subclinical involvement by HL by morphology/immunohistochemistry, and to define patient and treatment factors predictive of oocyte yield. This was a retrospective analysis of 26 ovarian tissue samples harvested for cryopreservation from women with HL. Histology, immunohistochemistry and follicle density (number mm(-3)) was examined. Disease status and preharvest chemotherapy details were obtained on 24 patients. The median age was 22 years (range 13-29). Seven of 24 patients had infradiaphragmatic disease at time of harvest. Nine of 20 patients had received chemotherapy preharvest (ABVD (Adriamycin), Bleomycin, Vinblastine and Dacarbazine) = 7, other regimens = 2). The seven receiving ABVD showed no difference in follicle density compared to patients not receiving treatment (n = 14); (median = 1555 vs 1620 mm3 P = 0.97). Follicle density measurement showed no correlation with patient age (R2 = 0.0001, P = 0.99). There was no evidence of HL involvement in the 26 samples examined (95% CI = 0-11%). In conclusion, subclinical involvement of HL has not been identified in ovarian tissue, even when patients have infradiaphragmatic disease. Furthermore, the quality of tissue harvested does not appear to be adversely affected by patient's age or prior ABVD chemotherapy.


Subject(s)
Cryopreservation , Hodgkin Disease , Infertility, Female/prevention & control , Oocytes , Reproductive Techniques, Assisted , Tissue Preservation , Adolescent , Adult , Age Factors , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bleomycin/administration & dosage , Dacarbazine/administration & dosage , Doxorubicin/administration & dosage , Female , Humans , Immunohistochemistry , Ovarian Follicle/pathology , Ovarian Follicle/physiology , Retrospective Studies , Vinblastine/administration & dosage
7.
Bone Marrow Transplant ; 37(5): 523-6, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16435012

ABSTRACT

Hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (HSCT) can cause significant morbidity and mortality. Previous reports have suggested a role for estrogen in the control of HC in adult patients. Here, we describe the clinical courses of 10 children and adolescents treated with estrogen for HC following HSCT. Eight patients (80%) experienced a significant improvement in their hematuria following the commencement of therapy, with six (60%) undergoing resolution of macroscopic hematuria, without any recurrences. The treatment was well tolerated by the majority of patients, with only one patient needing to interrupt treatment (hepatotoxicity). We conclude that estrogen is well tolerated and often effective, and should be considered as an adjunctive treatment option in children and adolescents with HC following HSCT.


Subject(s)
Bone Marrow Transplantation/adverse effects , Cystitis/drug therapy , Estrogens/administration & dosage , Adolescent , Bone Marrow Transplantation/methods , Chemical and Drug Induced Liver Injury , Child , Cystitis/pathology , Estrogens/toxicity , Female , Hematuria/drug therapy , Hemorrhage , Humans , Male , Treatment Outcome
8.
Int J Pediatr Otorhinolaryngol ; 61(1): 83-6, 2001 Oct 19.
Article in English | MEDLINE | ID: mdl-11576635

ABSTRACT

Laryngo-pharyngeal carcinoma is rare in children. We present two cases of squamous cell carcinoma of the laryngopharynx in children less than 15 years of age. Both patients presented with a prolonged history of symptoms and extensive disease at diagnosis. Early visualisation the vocal cords with flexible larygnoscopy is important in children presenting with symptoms suggestive of laryngeal pathology. Long-term complications of definitive local therapy for laryngopharyngeal carcinoma are important in young children. Evidence from studies in adult patients suggests that adjuvant chemotherapy may play a role in laryngeal preservation in a select group of patients.


Subject(s)
Carcinoma, Squamous Cell/pathology , Laryngeal Neoplasms/pathology , Pharyngeal Neoplasms/pathology , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/therapy , Chemotherapy, Adjuvant , Child , Humans , Laryngeal Neoplasms/diagnosis , Laryngeal Neoplasms/therapy , Laryngoscopy , Male , Pharyngeal Neoplasms/diagnosis , Pharyngeal Neoplasms/therapy
10.
J Biol Chem ; 276(38): 36035-42, 2001 Sep 21.
Article in English | MEDLINE | ID: mdl-11461921

ABSTRACT

Fibrillin-1 is a major constituent of the 10-12 nm extracellular microfibrils. Here we identify, characterize, and localize heparin/heparan sulfate-binding sites in fibrillin-1 and report on the role of such glycosaminoglycans in the assembly of fibrillin-1. By using different binding assays, we localize two calcium-independent heparin-binding sites to the N-terminal (Arg(45)-Thr(450)) and C-terminal (Asp(1528)-Arg(2731)) domains of fibrillin-1. A calcium-dependent-binding site was localized to the central (Asp(1028)-Thr(1486)) region of fibrillin-1. Heparin binding to these sites can be inhibited by a highly sulfated and iduronated form of heparan sulfate but not by chondroitin 4-sulfate, chondroitin 6-sulfate, and dermatan sulfate, demonstrating that the heparin binding regions represent binding domains for heparan sulfate. When heparin or heparan sulfate was added to cultures of skin fibroblasts, the assembly of fibrillin-1 into a microfibrillar network was significantly reduced. Western blot analysis demonstrated that this effect was not due to a reduced amount of fibrillin-1 secreted into the culture medium. Inhibition of the attachment of glycosaminoglycans to core proteins of proteoglycans by beta-d-xylosides resulted in a significant reduction of the fibrillin-1 network. These studies suggest that binding of fibrillin-1 to proteoglycan-associated heparan sulfate chains is an important step in the assembly of microfibrils.


Subject(s)
Heparin/metabolism , Heparitin Sulfate/metabolism , Microfilament Proteins/metabolism , Base Sequence , DNA Primers , Fibrillin-1 , Fibrillins , Glycosaminoglycans/metabolism , Humans , Microfilament Proteins/antagonists & inhibitors , Protein Binding , Recombinant Proteins/metabolism
11.
Arch Biochem Biophys ; 391(1): 65-71, 2001 Jul 01.
Article in English | MEDLINE | ID: mdl-11414686

ABSTRACT

An early step in the biosynthesis of dermatan sulfate is polymerization to chondroitin, which then is modified by the D-glucuronyl C5-epimerase and mainly 4-O-sulfotransferase. The final structure of the dermatan sulfate side chains varies and our aim was to identify, which of the two enzymes that are crucial to generate dermatan sulfate copolymeric structures in tissues. Dermatan sulfate side chains of biglycan and decorin were prepared from fibroblasts and nasal and articular chondrocytes and characterized regarding detailed structure. Microsomes were prepared from these cells and the activities of D-glucuronyl C5-epimerase and 4-O-sulfotransferase were determined. Chondrocytes from nasal cartilage synthesized biglycan and decorin containing 10%, articular chondrocytes 20--30%, and fibroblast 80% of the uronosyl residues in the l-iduronyl configuration. All three tissues contained high amount of 4-O-sulfotransferase activity. The activity of d-glucuronyl C5-epimerase showed different relationships. Fibroblasts contained a high level of the epimerase activity, articular chondrocytes intermediary activity, and in nasal cartilage it was barely detectable. The data indicate that the activity of the d-glucuronyl C5-epimerase is the main factor for formation of dermatan sulfate in tissues.


Subject(s)
Carbohydrate Epimerases/metabolism , Chondrocytes/enzymology , Dermatan Sulfate/biosynthesis , Fibroblasts/enzymology , Animals , Cattle , Cells, Cultured , Chondrocytes/metabolism , Fibroblasts/metabolism , Humans , Proteoglycans/biosynthesis , Sulfotransferases/metabolism
12.
Blood ; 97(10): 2962-71, 2001 May 15.
Article in English | MEDLINE | ID: mdl-11342418

ABSTRACT

In order to compare the outcomes of unrelated umbilical cord blood transplants (UCBTs) or bone marrow transplants, 541 children with acute leukemia (AL) transplanted with umbilical cord blood (n = 99), T-cell-depleted unrelated bone marrow transplants (T-UBMT) (n = 180), or nonmanipulated (UBMT) (n = 262), were analyzed in a retrospective multicenter study. Comparisons were performed after adjustment for patient, disease, and transplant variables. The major difference between the 3 groups was the higher number in the UCBT group of HLA mismatches (defined by serology for class I and molecular typing for DRB1). The donor was HLA mismatched in 92% of UCBTs, in 18% of UBMTs, and in 43% of T-UBMTs (P <.001). Other significant differences were observed in pretransplant disease characteristics, preparative regimens, graft-versus-host disease (GVHD) prophylaxis, and number of cells infused. Nonadjusted estimates of 2-year survival and event-free survival rates were 49% and 43%, respectively, in the UBMT group, 41% and 37% in the T-UBMT group, and 35% and 31% in the UCBT group. After adjustment, differences in outcomes appeared in the first 100 days after the transplantation. Compared with UBMT recipients, UCBT recipients had delayed hematopoietic recovery (Hazard ratio [HR] = 0.37; 95% confidence interval [95CI]: 0.27-0.52; P <.001), increased 100 day transplant-related mortality (HR = 2.13; 95CI: 1.20-3.76; P <.01) and decreased acute graft-versus-host disease (aGVHD) (HR = 0.50; 95CI: 0.34-0.73; P <.001). T-UBMT recipients had decreased aGVHD (HR = 0.25; 95CI: 0.17-0.36; P <.0001) and increased risk of relapse (HR = 1.96; 95CI: 1.11-3.45; P =.02). After day 100 posttransplant, the 3 groups achieved similar results in terms of relapse. Chronic GVHD was decreased after T-UBMT (HR = 0.21; 95CI: 0.11-0.37; P <.0001) and UCBT (HR = 0.24; 95CI: 0.01-0.66; P =.002), and overall mortality was higher in T-UBMT recipients (HR = 1.39; 95CI: 0.97-1.99; P <.07). In conclusion, the use of UCBT, as a source of hematopoietic stem cells, is a reasonable option for children with AL lacking an acceptably matched unrelated marrow donor.


Subject(s)
Bone Marrow Transplantation , Fetal Blood/cytology , Hematopoietic Stem Cell Transplantation , Leukemia/surgery , Treatment Outcome , Analysis of Variance , Child , Child, Preschool , Disease-Free Survival , Female , Graft vs Host Disease , Humans , Leukemia, Myeloid, Acute/mortality , Leukemia, Myeloid, Acute/surgery , Male , Precursor Cell Lymphoblastic Leukemia-Lymphoma/mortality , Precursor Cell Lymphoblastic Leukemia-Lymphoma/surgery , Recurrence , Registries , Retrospective Studies , Tissue Donors , Transplantation Conditioning
14.
Br J Haematol ; 104(1): 37-43, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10027709

ABSTRACT

In this study, two amino acid substitutions, Arg260His and Val414Phe, have been identified in the factor XIIIA subunits of factor XIII deficient patients of Syrian and Indian descent, respectively. To confirm the deleterious effects of these substitutions, both variant sequences have been engineered into cDNA clones and the mutant enzymes expressed in yeast. Determination of the transglutaminase activity and immuno detection of the mutant enzymes together with mRNA hybridization revealed that the mutations dramatically reduce both the catalytic activity and the level of enzyme expressed in yeast. The mutations Arg260His and Val414Phe occur within the 'core' domain of the enzyme. Computer modelling of the mutant enzymes reveals that the substitution of the Arg260 by His results in the loss of a conserved electrostatic interaction whereas the effect of the Val414Phe substitution is a consequence of the large increase in side-chain volume. Although both mutations do not effect the active site directly, they are predicted to reduce the stability of the enzyme. The effects of these two amino acid substitutions on enzyme expression and three-dimensional structure strongly confirm that residues which are located outside of the active site can have a significant effect on protein stability and function.


Subject(s)
Mutation, Missense/genetics , Transglutaminases/genetics , Adult , Computer Simulation , Female , Humans , Male , Nucleic Acid Hybridization , Pedigree , RNA, Messenger/metabolism , Transglutaminases/deficiency , Transglutaminases/metabolism
15.
Cancer ; 80(3): 489-96, 1997 Aug 01.
Article in English | MEDLINE | ID: mdl-9241083

ABSTRACT

BACKGROUND: Children with solid tumors that progress or recur after conventional multimodality therapies have a very poor prognosis. In a pilot study, vincristine, etoposide, and dose-escalated cyclophosphamide (VETOPEC) was shown to be a promising salvage regimen. Continued accrual of patients and increased duration of follow-up has resulted in substantial experience with VETOPEC. METHODS: Between May 1991 and March 1994, 56 pediatric patients from 6 centers were enrolled in this study; 44 had recurrent or progressive tumors (Group A) and 12 had newly diagnosed, advanced tumors with a very poor prognosis (Group B). The VETOPEC regimen was comprised of vincristine, 0.05 mg/kg, on Days 1 and 14; etoposide, 2.5 mg/kg, on Days 1, 2, and 3; and fractionated, dose-escalated cyclophosphamide on Days 1, 2, and 3. The initial cyclophosphamide dose was 90 mg/kg (2.7 g/m2)/cycle with an escalation of 15 mg/kg/cycle in each subsequent cycle, to a maximum (over 6 cycles) of 165 mg/kg (5.0 g/m2)/cycle. Tumor response was evaluated every two to three cycles and included central review of imaging. RESULTS: The combined and partial response rates for Groups A and B were 66% (25 of 38 patients) and 91% (10 of 11 patients), respectively. In Group A, best evaluable responses and event free (EF) survivors were observed with: brain tumors (7 of 9 patients; 2 EF at 39 and 45 months [mos], respectively), Wilms' tumor (6 of 7 patients; 3 EF at 37-49 mos), and lymphoma (4 of 4 patients; 2 EF at 52 and 59 mos, respectively); in Group B best evaluable responses and EF were observed with: neuroblastoma (5 of 6 patients; 1 disease free at 57 mos) and rhabdomyosarcoma (4 of 4 patients; no survivors). Hematologic toxicity was limiting despite support with myeloid growth factors in 33 patients. Four deaths in Group A and one in Group B were directly associated with this toxicity. Specifically, no cases of drug-related myocardial toxicity or pneumonitis were observed. CONCLUSIONS: This chemotherapy regimen with its intense scheduling produced a high response rate and appreciable survival in patients with a variety of recurrent, progressive, or advanced solid tumors of childhood.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Neoplasms/drug therapy , Adolescent , Adult , Child , Child, Preschool , Cyclophosphamide/administration & dosage , Drug Administration Schedule , Etoposide/administration & dosage , Granulocyte Colony-Stimulating Factor/therapeutic use , Granulocyte-Macrophage Colony-Stimulating Factor/therapeutic use , Humans , Infant , Neoplasm Metastasis , Survival Analysis , Vincristine/administration & dosage
16.
Med Pediatr Oncol ; 29(2): 108-14, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9180912

ABSTRACT

PURPOSE: Combination chemotherapy with vincristine, etoposide, and high-dose, escalating cyclophosphamide (VETOPEC) is an effective regimen in pediatric patients with high-risk solid tumors. The toxicity of the regimen is predominantly haematologic. This study addressed the role of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) following each cycle of chemotherapy in decreasing neutropaenia, incidence of fever/ hospitalization, and/or increasing chemotherapy dose-intensity. PATIENTS AND METHODS: Twenty-nine children with recurrent solid tumors were treated with the VETOPEC regimen. Sequential cohorts of patients received no GM-CSF (Group I), or GM-CSF in a dosage of 5 micrograms/kg/day (Group II) or 10 micrograms/kg/day (Group III) on days 4-18 of each chemotherapy cycle. Up to four cycles of chemotherapy were analysed with respect to haematopoietic recovery, clinical parameters, and dose intensity. RESULTS: Neutrophil recovery was significantly more rapid in patients treated with GM-CSF. Time to achieving an absolute neutrophil count (ANC) over 0.5 x 10(9)/L in Groups I, II, and III were 21, 18, and 16 days, respectively (P < 0.0001). Time to achieving an absolute neutrophil count (ANC) over 1.0 x 10(9)/L in Groups I, II, and III were 24, 19, and 17 days, respectively (P < 0.0001). There was no significant difference in the incidence of febrile neutropaenia between the three groups. Febrile neutropaenia occurred following 42, 68, and 62% of chemotherapy cycles in Groups I, II, and III, respectively (P = 0.27). Chemotherapy dose intensity was not different between the three groups. GM-CSF was associated with pericarditis and myalgias in one patient, and transient hypoxia/hypotension in another. CONCLUSION: GM-CSF led to significantly more rapid neutrophil recovery following VETOPEC chemotherapy, but did not lead to any demonstrable clinical benefit, either in reducing febrile events, or in increasing chemotherapy dose intensity.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Granulocyte-Macrophage Colony-Stimulating Factor/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Neoplasms/drug therapy , Adolescent , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Child , Child, Preschool , Cyclophosphamide/administration & dosage , Drug Administration Schedule , Etoposide/administration & dosage , Humans , Infant , Neutropenia/chemically induced , Neutropenia/drug therapy , Vincristine/administration & dosage
17.
Hum Immunol ; 55(2): 163-9, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9361968

ABSTRACT

The one-way mixed lymphocyte reaction (MLR-1) response was measured in both directions in 50 HLA-A, B, DR and DQ identical pairs and the role of DP studied in MLR stimulation. DR, DQ and DP typing was performed at the allele level by the polymerase chain reaction-sequence specific oligotyping (PCR-SSO) technique. The group consisted of 19 potential bone marrow transplant recipients and 34 matched unrelated donors. When more than one matched donor was available for a patient, donor/donor MLR-1 was also studied. DP identity was observed in 3 out of 50 pairs (6%), however due to homozygosity no incompatibility was present in the stimulating cells in 21 out of 100 cases (21%). There was a significant difference in the range of relative responses (RR) between zero DPB1 mismatches and one (p = 0.002) and two (p = 0.02) DPB1 mismatches: 52.4% of cases in the zero DPB1 mismatch group had RR < 1.0% compared with 31.6% and 27.3% in the one and two DPB1 mismatches. Stimulation by DPB1*0201 and 0301 gave the highest RR (12.9 +/- 22.5 and 17.5 +/- 17.0, respectively) while stimulation with DPB1*0401 and 0402 resulted in low levels of T cell response (1.3 +/- 8.2 and 0.6 +/- 11.5, respectively). When the responses were restricted to DPB1*0401 homozygotes to standardise for responder type similar results were obtained (DPB1*0201 v DPB1*0402 p = 0.008). The protein products of the DPB1*0201 and 0402 alleles differ by a single amino acid at position 69 (DPB1*0402--Lysine, DPB1*0201--glutamic acid). A further analysis was performed therefore scoring responders and stimulators as glutamic acid positive (E+) or negative (E-). There was a highly significant increase in the response to E+ stimulators compared with E- stimulators (p = 0.004). There was also a significant difference in the distribution of relative responses between the E+ stimulator group and the subgroups of E- responders/E- stimulators (p = 0.012) and E+ responders/E- stimulators (p = 0.009). However the amino acid difference at position 69 does not explain all responses due to DP in the MLR-1 as evidenced by the strong responses observed in cases where DPB1*0301 (lysine pos.) was the only difference on the stimulator cells. The results indicate that not all DP incompatibilities elicit a measurable T cell MLR response, but where a response does occur residue 69 in the first domain of DP appears to be pivotal. These results may have implications with respect to GVHD in bone marrow transplantation.


Subject(s)
HLA-DP Antigens/immunology , Lymphocyte Activation , T-Lymphocytes/immunology , Alleles , Animals , Graft vs Host Disease/etiology , HLA-DP Antigens/genetics , HLA-DP beta-Chains , Humans , Lymphocyte Culture Test, Mixed , Rabbits , Structure-Activity Relationship
18.
Matrix Biol ; 15(7): 469-78, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9106158

ABSTRACT

We have studied the effects of cytokines, separately or in combination, on the production of proteoglycans in confluent cultures of fibroblasts. The cytokines used were the transforming growth factor-beta (TGF-beta), the platelet derived growth factor-AA (PDGF-AA), the platelet derived growth factor-BB (PDGF-BB) and the epidermal growth factor (EGF). Hyaluronan production increased in cells treated with TGF-beta, PDGF-AA and PDGF-BB. Combining pairs of factors did not contribute further to hyaluronan production, whereas the triple combination of EGF, TGF-beta and PDGF-BB induced an additional 1.9-fold increase. Proteoglycan production was only increased by TGF-beta alone. As for hyaluronan, combining pairs of the cytokines had no further effect on metabolism, whereas the combination of EGF, TGF-beta and PDGF-BB induced a further 1.6-fold increase in production and secretion. Compared with the control, an extensive increase in proteoglycan production was generated by the combination of EGF, TGF-beta and PDGF-BB, 7-fold for biglycan, approximately 5-fold for versican and hyaluronan and 2.4-4-fold for heparan sulfate proteoglycan and decorin. Compared with TGF-beta alone, this combination increased, in falling order, the production of heparan sulfate proteoglycan, hyaluronan, biglycan, decorin and versican. The mRNA levels for the various proteoglycans did not completely agree with the changes in production, suggesting that changes not only in synthesis but also in rate of degradation generate these variations. The data indicate that cytokines cooperate to produce a proper and physiological response, one needed by the organism during physiological and pathophysiological remodeling.


Subject(s)
Cytokines/pharmacology , Fibroblasts/drug effects , Proteoglycans/metabolism , Anticoagulants/pharmacology , Becaplermin , Cells, Cultured , Drug Synergism , Fibroblasts/physiology , Humans , Hyaluronic Acid/metabolism , Hyaluronic Acid/pharmacology , Platelet-Derived Growth Factor/pharmacology , Proteoglycans/drug effects , Proto-Oncogene Proteins c-sis , Transforming Growth Factor beta/pharmacology
19.
Biochem J ; 313 ( Pt 2): 589-96, 1996 Jan 15.
Article in English | MEDLINE | ID: mdl-8573097

ABSTRACT

The capsular polysaccharide from Escherichia coli K4 consists of a chondroitin ([GlcA(beta 1-->3)GalNAc(beta 1-->4)]n) backbone, to which beta-fructofuranose units are linked to C-3 of D-glucuronic acid (GlcA) residues. Removal of the fructose units by mild acid hydrolysis provided a substrate for the GlcA C-5 epimerase, which is involved in the generation of L-iduronic acid (IdoA) units during dermatan sulphate biosynthesis. Incubation of this substrate with solubilized fibroblast microsomal enzyme in the presence of 3H2O resulted in the incorporation of tritium at C-5 of hexuronyl units. A Km of 67 x 10(-6) M hexuronic acid (equivalent to disaccharide units) was determined, which is similar to that (80 x 10(-6) M) obtained for dermatan (desulphated dermatan sulphate). Vmax was about 4 times higher with dermatan than with the K4 substrate. A defructosylated K4 polysaccharide isolated after incubation of bacteria with D-[5-3H]glucose released 3H2O on reaction with the epimerase, and thus could be used to assay the enzyme. Incubation of a K4 substrate with solubilized microsomal epimerase for 6 h in the presence of 3H2O resulted in the formation of about 5% IdoA and approximately equal amounts of 3H in GlcA and IdoA. A corresponding incubation of dermatan yielded approx. 22% GlcA, which contained virtually all the 3H label. These results are tentatively explained in terms of a two-base reaction mechanism, involving a monoprotic L-ido-specific base and a polyprotic D-gluco-specific base. Most of the IdoA residues generated by the enzyme occurred singly, although some formation of two or three consecutive IdoA-containing disaccharide units was observed.


Subject(s)
Dermatan Sulfate/biosynthesis , Escherichia coli/metabolism , Fructose/metabolism , Polysaccharides, Bacterial/metabolism , Bacterial Capsules , Carbohydrate Epimerases/metabolism , Carbohydrate Sequence , Humans , Molecular Sequence Data , Substrate Specificity
20.
Arch Dis Child ; 74(1): 27-31, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8660041

ABSTRACT

Recent studies have suggested that Epstein-Barr virus (EBV) may play a role in the aetiology of Hodgkin's disease. To determine the role of EBV in childhood Hodgkin's disease in different geographical areas, immunohistochemical staining and in situ hybridisation were used to analyse latent membrane protein 1 (LMP 1) and small nuclear non-transcribed RNAs (EBER-1) respectively. Testing for EBV within the Reed-Sternberg and Hodgkin's cells was carried out in childhood Hodgkin's disease from 10 different countries. The proportion of LMP 1 positive cases varied significantly, being 50% of cases from the United Kingdom (38/75), South Africa (9/18), Egypt (7/14), and Jordan (8/16), 60% from the United Arab Emirates (6/10), 70% from Australia (11/16), 81% from Costa Rica (34/42), 88% from Iran (7/8), 90% from Greece (20/22), and 100% of the 56 cases from Kenya. A sensitive polymerase chain reaction based EBV strain typing technique was established using archival tissues. EBV strain type 1 was shown to be predominant in childhood Hodgkin's disease from the United Kingdom, South Africa, Australia, and Greece. Type 2 was predominant in Egypt. EBV strain types 1 and 2 were both detected in some cases of childhood Hodgkin's disease in the United Kingdom, Costa Rica, and Kenya. The high incidence of EBV and the presence especially in developing countries of dual infection with both strain types 1 and 2 may reflect socioeconomic conditions leading to malnutrition induced immunological impairment. The possibility of HIV infection also needs to be explored.


Subject(s)
Herpesviridae Infections/complications , Herpesvirus 4, Human/isolation & purification , Hodgkin Disease/virology , Tumor Virus Infections/complications , Adolescent , Child , Child, Preschool , Female , Herpesvirus 4, Human/classification , Hodgkin Disease/epidemiology , Hodgkin Disease/pathology , Humans , Immunoenzyme Techniques , In Situ Hybridization , Incidence , Male , Viral Matrix Proteins/analysis
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