Biomedical subjects

Tomomitsu Hotta

Publications and source records attributed to Tomomitsu Hotta.

At least 19 recordsLinked to original sources

PubMed2006

Once-weekly epoetin-beta improves hemoglobin levels in cancer patients with chemotherapy-induced anemia: A randomized, double-blind, dose-finding study.

OBJECTIVE: To determine a recommended dose of once-weekly epoetin-beta administration for anemic cancer patients receiving myelosuppressive chemotherapy, we conducted a multicenter, randomized, double-blind trial. METHODS: A total of 86 patients with malignant lymphoma or lung cancer who received chemotherapy containing platinum, taxanes or anthracyclines were enrolled in the study. Patients were randomly assigned into groups that received three dose levels of epoetin-beta (9000, 18,000 or 36,000 IU) administered subcutaneously once a week for 12 weeks. The primary endpoint was change in hemoglobin, while the secondary endpoints were quality of life (QOL) assessed by Functional Assessment of Cancer Therapy-Anemia (FACT-An) questionnaire and transfusion requirements. RESULTS: Among the 69 patients (per protocol set population) assessable for efficacy, hemoglobin level change in the 36,000 IU group was significantly greater than that in the 9000 IU group (1.75 +/- 2.15 versus 0.04 +/- 1.98 g/dl; P = 0.009), and a significant dose-response relationship was observed for the change in hemoglobin level (P = 0.003). Although changes in FACT-An Total Fatigue subscale (Fatigue subscale) scores were similar for the three dosage groups, there was a statistically significant correlation (r = 0.435, P < 0.001) between the change in hemoglobin levels and the change in Fatigue subscale scores. The proportion of transfused patients was significantly smaller in the 36 000 IU group compared with that in the 9000 IU group (P = 0.022, not adjusted for pre-study transfusions). The incidence of adverse events was similar in the three dosage groups. CONCLUSIONS: Once-weekly epoetin-beta 36,000 IU for 12 weeks was well tolerated and significantly increased hemoglobin levels in anemic cancer patients receiving chemotherapy.

Adult↗

PubMed2006

Health-related quality of life among Japanese women with iron-deficiency anemia.

Iron-deficiency anemia (IDA) is a common disease in females of childbearing age. Although iron supplementation quickly improves laboratory-measured parameters, its effect on health-related quality of life is unknown. Here, we conducted a prospective follow-up study to evaluate health-related quality of life in pre-menopausal women diagnosed with IDA. A convenience sample of 92 patients who visited Tokai University Hospital and three other affiliated hospitals were asked to fill out the Medical Outcome Study 36-item short-form health survey (SF-36) during the course of treatment (baseline, and 1 and 3 months after the start of treatment). At baseline, vitality and general health scores were significantly lower than the Japanese national norms. After the start of therapy, however, a significant improvement was seen in all domain scores except role emotional (RE), and at 3 months all eight scores were comparable to or greater than the national norms. In particular, physical functioning and vitality scores of patients with a lower hemoglobin level ( < 9.0 g/dl) at baseline showed a dramatic improvement. Iron supplementation in IDA patients improves not only hemoglobin levels, but also physical function, vitality, and general health perception.

Adolescent↗

PubMed2006

Clonal analysis of thymus-repopulating cells presents direct evidence for self-renewal division of human hematopoietic stem cells.

To elucidate the in vivo kinetics of human hematopoietic stem cells (HSCs), CD34+CD38- cells were infected with lentivirus vector and transplanted into immunodeficient mice. We analyzed the multilineage differentiation and self-renewal abilities of individual thymus-repopulating clones in primary recipients, and their descending clones in paired secondary recipients, by tracing lentivirus gene integration sites in each lymphomyeloid progeny using a linear amplification-mediated polymerase chain reaction (PCR) strategy. Our clonal analysis revealed that a single human thymus-repopulating cell had the ability to produce lymphoid and myeloid lineage cells in the primary recipient and each secondary recipient, indicating that individual human HSCs expand clonally by self-renewal division. Furthermore, we found that the proportion of HSC clones present in the CD34+ cell population decreased as HSCs replicated during extensive repopulation and also as the differentiation capacity of the HSC clones became limited. This indicates the restriction of the ability of individual HSCs despite the expansion of total HSC population. We also demonstrated that the extensive self-renewal potential was confined in the relatively small proportion of HSC clones. We conclude that our clonal tracking studies clearly demonstrated that heterogeneity in the self-renewal capacity of HSC clones underlies the differences in clonal longevity in the CD34+ stem cell pool.

ADP-ribosyl Cyclase 1↗

PubMed2006

Feasibility of using a human nucleus pulposus cell line as a cell source in cell transplantation therapy for intervertebral disc degeneration.

STUDY DESIGN: Assessment of the potential use of an immortalized human nucleus pulposus cell line as an alternative cell source in cell transplantation therapy for intervertebral disc degeneration. OBJECTIVES: To evaluate the effect of transplanting the human nucleus pulposus cell line into a disc degeneration model in rabbits and to define whether it is capable of becoming an alternative cell source for cell transplantation therapy for disc degeneration. SUMMARY OF BACKGROUND DATA: Interest in cell transplantation therapy for disc degeneration has been growing for several years, and a range of different cell types have been examined as possible donor cells. In addition, the establishment of a novel cell line that possesses some of the major characteristics of a normal human nucleus pulposus cells has been reported. METHODS: Human nucleus pulposus cell line was established, and cells were transplanted into a rabbit disc degeneration model. At 4, 8, and 24 weeks after transplantation, inhibition of intervertebral disc degeneration was assessed by examining the disc height, macroscopic appearance, histologic findings, and immunohistochemistry. In addition, aggrecan, versican, and Type II collagen gene expression in the nucleus pulposus were measured semiquantitatively at the mRNA level. Furthermore, the survival of transplanted cells was examined using immunohistochemistry for Simian Virus 40 T antigen, and the presence of graft-versus-host reaction was assessed by immunohistochemistry for CD4 and CD58. RESULTS: The disc height was significantly greater in the transplanted group than in the degenerative group's disc from 4 weeks' posttransplantation. Macroscopically, the nucleus pulposus was absent and there was loss of disc height in the degenerative group at 24 weeks after transplantation, whereas the nucleus pulposus was preserved in the transplanted group. Histologic examination showed that the structure of the inner anulus fibrosus was significantly preserved in the transplanted group, and the boundary between the nucleus and anulus could be clearly visualized. Expression of mRNAs of the nucleus pulposus matrix, aggrecan, and Type II collagen was significantly greater in the transplanted group than in the degenerative group. This indicates that transplantation of human nucleus pulposus cell line helped to preserve the matrix of the nucleus pulposus. Thus, transplantation of a human nucleus pulposus cell line was shown to delay disc degeneration in this rabbit model. CONCLUSION: The human nucleus pulposus cell line may become an alternative cell source for cell transplantation therapy of intervertebral disc degeneration.

Adult↗

PubMed2006

Myeloablative allogeneic hematopoietic stem cell transplantation for non-Hodgkin lymphoma: a nationwide survey in Japan.

We retrospectively surveyed the data of 233 patients who underwent myeloablative allogeneic hematopoietic stem cell transplantation (allo-HSCT) for non-Hodgkin lymphoma (NHL). Donors were HLA-matched relatives in 154 patients (66%) or unrelated volunteers in 60 (26%). Ninety patients (39%) were in complete remission. One hundred ninety-three (83%) received a total body irradiation (TBI)-based regimen, and 40 (17%) received a non-TBI-based regimen. Acute graft-versus-host disease (GVHD) occurred in 155 (67%) of the 233 evaluable patients; grade II to IV in 90 (39%), and grade III to IV in 37 (16%). Treatment-related mortality (TRM) was observed in 98 patients (42%), and 68% of them were related to GVHD. In a multivariate analysis, chemoresistance, prior autograft, and chronic GVHD were identified as adverse prognostic factors for TRM. Relapse or progression of lymphoma was observed in 21%. The 2-year overall survival rates of the patients with indolent (n = 38), aggressive (n = 111), and lymphoblastic lymphoma (n = 84) were 57%, 42%, and 41%, respectively. In a multivariate analysis, chemoresistance, prior autograft, and prior radiotherapy were identified as adverse prognostic factors for overall survival. Although myeloablative allo-HSCT represents an effective therapeutic option for patients with NHL, more work is still needed to decrease TRM and relapse.

Acute Disease↗

PubMed2006

Administration of hematopoietic cytokines in the subacute phase after cerebral infarction is effective for functional recovery facilitating proliferation of intrinsic neural stem/progenitor cells and transition of bone marrow-derived neuronal cells.

BACKGROUND: Hematopoietic cytokines, granulocyte colony-stimulating factor (G-CSF), and stem cell factor (SCF) were reported to show a neuroprotective effect or to support neurogenesis. These cytokines also mobilize bone marrow (BM) cells into the brain, and the BM-derived cells differentiate into neuronal cells. We administered these hematopoietic cytokines after focal cerebral ischemia and assessed their effects and the therapeutic time window for neuronal regeneration. METHODS AND RESULTS: We induced permanent middle cerebral artery occlusion in mice whose BM had been replaced with BM cells from green fluorescent protein (GFP)-transgenic mice. The occluded mice were treated with G-CSF and SCF in the acute phase (days 1 to 10) or subacute phase (days 11 to 20), and the brain functions and histological changes were evaluated. Separately, we injected bromodeoxyuridine during cytokine treatment to assess cell kinetics in the brain. Six mice were prepared for each experimental group. Administration of G-CSF and SCF in the subacute phase effectively improved not only motor performance but also higher brain function, compared with acute-phase treatment. Acute-phase and subacute-phase treatments identically reduced the infarct volume relative to vehicle treatment. However, subacute-phase treatment significantly induced transition of BM-derived neuronal cells into the peri-infarct area and stimulated proliferation of intrinsic neural stem/progenitor cells in the neuroproliferative zone. CONCLUSIONS: Administration of G-CSF and SCF in the subacute phase after focal cerebral ischemia is effective for functional recovery, enhancing cytokine-induced generation of neuronal cells from both BM-derived cells and intrinsic neural stem/progenitor cells. Because G-CSF and SCF are available for clinical use, these findings suggest a new therapeutic strategy for stroke.

Animals↗

PubMed2006

Direct evidence for ex vivo expansion of human hematopoietic stem cells.

To characterize human hematopoietic stem cells (HSCs), xenotransplantation techniques such as the severe combined immunodeficiency (SCID) mouse repopulating cell (SRC) assay have proven the most reliable methods thus far. While SRC quantification by limiting dilution analysis (LDA) is the gold standard for measuring in vitro expansion of human HSCs, LDA is a statistical method and does not directly establish that a single HSC has self-renewed in vitro. This would require a direct clonal method and has not been done. By using lentiviral gene marking and direct intra-bone marrow injection of cultured CD34+ CB cells, we demonstrate here the first direct evidence for self-renewal of individual SRC clones in vitro. Of 74 clones analyzed, 20 clones (27%) divided and repopulated in more than 2 mice after serum-free and stroma-dependent culture. Some of the clones were secondary transplantable. This indicates symmetric self-renewal divisions in vitro. On the other hand, 54 clones (73%) present in only 1 mouse may result from asymmetric divisions in vitro. Our data demonstrate that current ex vivo expansion conditions result in reliable stem cell expansion and the clonal tracking we have employed is the only reliable method that can be used in the development of clinically appropriate expansion methods.

Animals↗

PubMed2006

Randomized phase II study of concurrent and sequential rituximab and CHOP chemotherapy in untreated indolent B-cell lymphoma.

CHOP combined with rituximab (R-CHOP) is regarded as one of the most effective treatments for indolent B-cell non-Hodgkin lymphoma (B-NHL), however, its optimal combination schedule remains unknown. We performed a randomized phase II study to explore a more promising schedule in untreated, advanced indolent B-NHL. Patients were randomized to receive either six courses of CHOP concurrently with rituximab (Arm C), or six courses of CHOP followed by six courses of weekly rituximab (Arm S). A total of 69 patients received the concurrent (n=34) or sequential (n=35) regimen. Overall response rate (ORR) in Arm C was 94% (95% confidence interval [CI], 79 to 99), including a 66% complete response (CR) compared with 97% (95% CI, 85-100), including a 68% CR in Arm S. Patients in Arm C experienced more grade 4 neutropenia (85%versus 70%) and experienced more grade 3 or greater non-hematological toxicities (21%versus 12%). Both arms were tolerated well. With a median follow-up of 28.2 months, the median progression-free survival (PFS) time was 34.2 months in Arm C, and was not reached in Arm S. R-CHOP is highly effective in untreated indolent B-NHL, either concurrent or in a sequential combination. Both combination schedules deserve further investigation.

Adult↗

PubMed2006

A phase II study of VEPA/FEPP chemotherapy for aggressive lymphoma in elderly patients: Japan Clinical Oncology Group Study JCOG9203.

The Lymphoma Study Group (LSG) of the Japan Clinical Oncology Group conducted a phase II trial of LSG12 therapy for 45 elderly patients with aggressive lymphoma to clarify whether LSG12 reduces severe infection without lowering the complete response (CR) rate in comparison with LSG4. LSG12, which consisted of a regimen of vincristine, cyclophosphamide, prednisolone, doxorubicin, vindesine, etoposide, and procarbazine (VEPA/FEPP), excluded bleomycin and methotrexate of LSG4 therapy, reduced the dosages of doxorubicin and cyclophosphamide, and increased etoposide and procarbazine dosages instead. Inclusion criteria consisted of a patient age of 70 to 75 years, a World Health Organization performance status of 0 to 2, and acceptable organ function. The treatment was completed in 47% of the patients and terminated early for disease progression in 20% and for toxicity in 16%. The CR rate was 60% (95% confidence interval [CI], 44%-74%). The 5-year overall survival (OS) rate was 42% (95% CI, 27%-57%), and the median OS time was 4.3 years. Leukopenia of grade 3 to 4 occurred in 98% of the patients, and severe infection occurred in 9%. Eight patients with hepatitis C virus (HCV) antibody showed no severe hepatic toxicity and had a better CR or OS rate than the 37 HCV-negative patients. Although the outcomes of LSG12 met our expectations with a reduction in severe infection and equivalent CR and OS outcomes compared with LSG4 and CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone), the possibility of a regimen more beneficial than LSG12 for aggressive lymphoma in the elderly patient should be explored because of frequent hematologic toxicity and poor compliance in LSG12.

Aged↗

PubMed2006

Lung injury associated with bortezomib therapy in relapsed/refractory multiple myeloma in Japan: a questionnaire-based report from the "lung injury by bortezomib" joint committee of the Japanese society of hematology and the Japanese society of clinical hematology.

Bortezomib is a proteasome inhibitor that can be effective in the treatment of refractory and relapsed multiple myeloma. Recently, severe pulmonary complications associated with bortezomib therapy have been reported in Japan. Because bortezomib has not yet been approved for general use in Japan and is imported by attending physicians on the request of patients, The Japanese Society of Hematology and The Japanese Society of Clinical Hematology sent urgent questionnaires to the councilors of both societies to explore the situation and the details of pulmonary complications associated with bortezomib therapy. Clinical details were available for 46 patients who had been treated with personally imported bortezomib in Japan. Seven patients (15.2%), including 3 who died from respiratory failure, showed complications definitely or probably caused by bortezomib. Of the 7 patients, 6 had a prior history of stem cell transplantation (SCT), whereas only 14 of 39 patients without lung injury had received SCT treatment (P = .033, Fisher exact test). Multivariate analysis revealed that the concomitant use of corticosteroids might reduce the risk of lung injury (P = .024; odds ratio, 0.055) and that a previous SCT might increase the risk (P = .042; odds ratio, 13.140). We summarized these data from questionnaires for a limited Japanese cohort and therefore do not know the precise incidence of lung injury linked to fatal progression. Thus, future verification concerning this matter is warranted after the approval of bortezomib for use in Japan. Clinicians should be aware of the possibility of severe pulmonary complications associated with bortezomib therapy.

Adrenal Cortex Hormones↗

PubMed2006

[Lung injury associated with bortezomib therapy in relapsed/refractory multiple myeloma in Japan: a questionnaire-based report from the "Lung Injury by Bortezomib" Joint Committee of the Japanese Society of Hematology and the Japanese Society of Clinical Hematology].

Bortezomib is a proteasome inhibitor that can be effective in the treatment of refractory and relapsed multiple myeloma. Recently, severe pulmonary complications associated with bortezomib therapy have been reported in Japan. Because bortezomib has not yet been approved for general use in Japan and is imported by attending physicians on the request of patients, The Japanese Society of Hematology and The Japanese Society of Clinical Hematology sent urgent questionnaires to the councilors of both societies in order to explore the situation and details of pulmonary complications associated with bortezomib therapy. Clinical details were available for 46 patients who had been treated with personally imported bortezomib in Japan. Seven patients (15.2%), including 3 who died from respiratory failure, showed complications definitely or probably caused by bortezomib. Of the 7 patients, 6 had a prior history of stem cell transplantation (SCT), whereas only 14 of 39 patients without lung injury had received SCT treatment (p = 0.033 by Fischer's exact test). Multivariate analysis revealed that the concomitant use of corticosteroids might reduce the risk of lung injury (p = 0.024; odds ratio = 0.055) and that a previous SCT might increase the risk (p = 0.042; odds ratio = 13.140). We summarized these data from questionnaires for a limited Japanese cohort and therefore do not know the precise incidence of lung injury linked to fatal progression. Thus, future verification concerning these matters is warranted after the approval of bortezomib for use in Japan. Clinicians should be aware of the possibility of severe pulmonary complications associated with bortezomib therapy. Note that this report has the same contents as the article appeared in the International Journal of Hematology (vol. 84, p406-412, 2006) by permission of both the editorials of the Japanese Society of Hematology and the Japanese Society of Clinical Hematology, and should be considered as the Japanese translation of the article.

Adrenal Cortex Hormones↗

PubMed2005

Phase II study of oral fludarabine phosphate in relapsed indolent B-Cell non-Hodgkin's lymphoma.

PURPOSE: Although intravenous (IV) fludarabine phosphate is effective against indolent B-cell non-Hodgkin's lymphoma (B-NHL), IV administration for 3 to 5 consecutive days is inconvenient in an outpatient setting. To assess the efficacy and toxicity of oral fludarabine phosphate in patients with indolent B-NHL, we conducted a multicenter phase II study. PATIENTS AND METHODS: Patients with relapsed indolent B-NHL received fludarabine phosphate tablets orally once daily on days 1 through 5 every 28 days for three to six cycles. The efficacy was separately analyzed in a mantle-cell lymphoma (MCL) cohort and indolent B-NHL except for MCL (IL) cohort. The primary end point was the overall response rate (ORR). RESULTS: Fifty-two patients, including 46 in the IL cohort (41 with follicular lymphoma) and six in the MCL cohort, were registered, and all patients were eligible. Forty-one patients (79%) had received rituximab as prior therapy. In the IL cohort, the ORR and complete response rate were 65% (30 of 46 patients; 95% CI, 50% to 79%) and 30% (14 of 46 patients; 95% CI, 18% to 46%), respectively. One of six patients with MCL achieved a partial response. The median times to treatment failure for the 46 patients in the IL cohort and for the six patients in the MCL cohort were 8.6 and 6.1 months, respectively. Hematologic toxicities, including grade 4 neutropenia (37%), were the most frequent toxicities, and nonhematologic toxicities were mild. CONCLUSION: Oral fludarabine phosphate is highly effective in patients with relapsed indolent B-NHL who have mostly been pretreated with rituximab and is more convenient than the IV formulation.

Administration, Oral↗

PubMed2005

Reconstitution of the functional human hematopoietic microenvironment derived from human mesenchymal stem cells in the murine bone marrow compartment.

Hematopoiesis is maintained by specific interactions between both hematopoietic and nonhematopoietic cells. Whereas hematopoietic stem cells (HSCs) have been extensively studied both in vitro and in vivo, little is known about the in vivo characteristics of stem cells of the nonhematopoietic component, known as mesenchymal stem cells (MSCs). Here we have visualized and characterized human MSCs in vivo following intramedullary transplantation of enhanced green fluorescent protein-marked human MSCs (eGFP-MSCs) into the bone marrow (BM) of nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice. Between 4 to 10 weeks after transplantation, eGFP-MSCs that engrafted in murine BM integrated into the hematopoietic microenvironment (HME) of the host mouse. They differentiated into pericytes, myofibroblasts, BM stromal cells, osteocytes in bone, bone-lining osteoblasts, and endothelial cells, which constituted the functional components of the BM HME. The presence of human MSCs in murine BM resulted in an increase in functionally and phenotypically primitive human hematopoietic cells. Human MSC-derived cells that reconstituted the HME appeared to contribute to the maintenance of human hematopoiesis by actively interacting with primitive human hematopoietic cells.

Animals↗

PubMed2005

Differentiation of mesenchymal stem cells transplanted to a rabbit degenerative disc model: potential and limitations for stem cell therapy in disc regeneration.

STUDY DESIGN: An in vivo study to assess the differentiation status of mesenchymal stem cells (MSCs) transplanted to the nucleus pulposus of degenerative discs in a rabbit model. OBJECTIVES: To evaluate the fate of MSCs transplanted to the nucleus pulposus of degenerative discs in a rabbit and to determine whether they are a suitable alternative for cell transplantation therapy for disc degeneration. SUMMARY OF BACKGROUND DATA: Although MSCs have been proposed as candidate donor cells for transplantation to treat intervertebral disc degeneration, their differentiation after transplantation has not been adequately investigated. METHODS: Autologous MSCs, labeled with green fluorescent protein, were transplanted into mature rabbits. Consecutive counts of transplanted MSCs in the nucleus area were performed for 48 weeks after transplantation. Differentiation of transplanted cells was determined by immunohistochemical analysis. The proteoglycan content of discs was measured quantitatively using a dimethylmethylene blue assay, and mRNA expression of Type I and II collagen, aggrecan and versican was measured semi-quantitatively using reverse transcription polymerase chain reaction. RESULTS: Many cells that were positive for green fluorescent protein were observed in the nucleus pulposus of cell-transplanted rabbit discs 2 weeks after transplantation. Their number increased significantly by 48 weeks. Some GFP-positive cells were positive for cell-associated matrix molecules, such as Type II collagen, keratan sulfate, chondroitin sulfate, aggrecan, and the nucleus pulposus phenotypic markers, hypoxia inducible factor 1 alpha, glutamine transporter 1, and matrix metalloproteinase 2. MSCs did not show significant expression of these molecules before transplantation. Biochemical and gene expression analyses showed significant restoration of total proteoglycan content and matrix-related genes compared with nontransplanted discs. CONCLUSIONS: MSCs transplanted to degenerative discs in rabbits proliferated and differentiated into cells expressing some of the major phenotypic characteristics of nucleus pulposus cells, suggesting that these MSCs may have undergone site-dependent differentiation. Further studies are needed to evaluate their functional role.

Animals↗

PubMed2005

Regenerative effects of transplanting mesenchymal stem cells embedded in atelocollagen to the degenerated intervertebral disc.

Intervertebral disc (IVD) degeneration, a common cause of low back pain in humans, is a relentlessly progressive phenomenon with no currently available effective treatment. In an attempt to solve this dilemma, we transplanted autologous mesenchymal stem cells (MSCs) from bone marrow into a rabbit model of disc degeneration to determine if stem cells could repair degenerated IVDs. LacZ expressing MSCs were transplanted to rabbit L2-L3, L3-L4 and L4-L5 IVDs 2 weeks after induction of degeneration. Changes in disc height by plain radiograph, T2-weighted signal intensity in magnetic resonance imaging (MRI), histology, immunohistochemistry and matrix associated gene expressions were evaluated between normal controls (NC) without operations, sham operated with only disc degeneration being induced, and MSC-transplanted animals for a 24-week period. Results showed that after 24 weeks post-MSC transplantation, degenerated discs of MSC-transplanted group animals regained a disc height value of about 91%, MRI signal intensity of about 81%, compared to NC group discs. On the other hand, sham-operated group discs demonstrated the disc height value of about 67% and MRI signal intensity of about 60%. Macroscopic and histological evaluations confirmed relatively preserved nucleus with circular annulus structure in MSC-transplanted discs compared to indistinct structure seen in sham. Restoration of proteoglycan accumulation in MSC-transplanted discs was suggested from immunohistochemistry and gene expression analysis. These data indicate that transplantation of MSCs effectively led to regeneration of IVDs in a rabbit model of disc degeneration as suggested in our previous pilot study. MSCs may serve as a valuable resource in cell transplantation therapy for degenerative disc disease.

Aggrecans↗

PubMed2005

Atelocollagen for culture of human nucleus pulposus cells forming nucleus pulposus-like tissue in vitro: influence on the proliferation and proteoglycan production of HNPSV-1 cells.

Nucleus pulposus (NP) is responsible for maintaining function and structure of the disc. Scaffolds to culture disc cells three-dimensionally are emphasized in recent reports on development of a new method for treating disc degeneration using cell transplantation and tissue engineering. Among artificial scaffolds and cell carrying materials, Atelocollagen is a collagen gel that has an advantage in safety issues over others. However, to date there has been no study that investigated culture of human nucleus pulposus cells in Atelocollagen. To investigate whether Atelocollagen could be used as a culture scaffold and if it has any effect on cell proliferation and proteoglycan (PG) production, as well as to find the optimal commercially available Atelocollagen for NP cell transplantation and tissue engineering, we cultured human NP cell line HNPSV-1, in three different Atelocollagen and compared with alginate. Furthermore, NP-like tissues were generated using these cells and different Atellocollagen solutions. Results showed that both DNA synthesis and content is significantly greater when cultured in Atelocollagen than in alginate. On the other hand, proteoglycan synthesis and accumulation was significantly greater in alginate compared with the 0.3% Atelocollagen scaffolds; with 3% Atelocollagen, however, results were similar. NP-like tissue generated by Atelocollagen showed good water and proteoglycan preservation. The current study demonstrates that the use of Atelocollagen as an in vitro culture scaffold for three-dimensional culture of human NP cell lines is indeed feasible and moreover, Atelocollagen possesses the potential to become a candidate scaffold for cell transplantation or tissue engineering for the treatment of intervertebral disc degeneration.

Adult↗

PubMed2005

Low-intensity pulsed ultrasound stimulates cell proliferation and proteoglycan production in rabbit intervertebral disc cells cultured in alginate.

Intervertebral disc degeneration, one of the major causes of low-back pain, is known to result from alteration in biosynthesis of proteoglycan in the disc. Therefore, upregulating the synthesis of proteoglycan in intervertebral disc cells may be one approach in treating disc degeneration. Based on the finding that low-intensity pulsed ultrasound stimulates proteoglycan synthesis in rat chondrocytes, we investigated whether low-intensity pulsed ultrasound stimulates biological properties of rabbit intervertebral disc cells in vitro. Nucleus pulposus cells and annulus fibrosus cells isolated from rabbits were cultured in alginate beads. Cells were stimulated for 20 min each day for 5-12 days, starting on the third day after seeding. An ultrasound signal consisting of a 200 micros burst sine wave of 0.5 MHz repeating at 1 kHz, with an intensity of 0, 7.5, 15, 30, 60, 120 mW/cm2 spatial and temporal average, was applied. DNA and proteoglycan synthesis were evaluated by measuring [3H]-thymidine and [35S]-sulfate incorporation. DNA and proteoglycan content in beads were measured by Hoechst 33258 dye method and dimethylmethylene blue assay. Results demonstrated positive effects on DNA synthesis and content, following low-intensity pulsed ultrasound stimulation with intensities of 7.5 and 15 mW/cm2. Furthermore, ultrasound stimulation significantly upregulated [35S]-sulfate incorporation and proteoglycan content compared to the control group, following 5 days of stimulation in both nucleus pulposus and annulus fibrosus cells. These findings suggest the possible application of low-intensity pulsed ultrasound in biological repair of intervertebral disc degeneration.

Alginates↗

PubMed2005

Whole genome association study of rheumatoid arthritis using 27 039 microsatellites.

A major goal of current human genome-wide studies is to identify the genetic basis of complex disorders. However, the availability of an unbiased, reliable, cost efficient and comprehensive methodology to analyze the entire genome for complex disease association is still largely lacking or problematic. Therefore, we have developed a practical and efficient strategy for whole genome association studies of complex diseases by charting the human genome at 100 kb intervals using a collection of 27,039 microsatellites and the DNA pooling method in three successive genomic screens of independent case-control populations. The final step in our methodology consists of fine mapping of the candidate susceptible DNA regions by single nucleotide polymorphisms (SNPs) analysis. This approach was validated upon application to rheumatoid arthritis, a destructive joint disease affecting up to 1% of the population. A total of 47 candidate regions were identified. The top seven loci, withstanding the most stringent statistical tests, were dissected down to individual genes and/or SNPs on four chromosomes, including the previously known 6p21.3-encoded Major Histocompatibility Complex gene, HLA-DRB1. Hence, microsatellite-based genome-wide association analysis complemented by end stage SNP typing provides a new tool for genetic dissection of multifactorial pathologies including common diseases.

Arthritis, Rheumatoid↗