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Wang ZL, Xu DS, Wang YX, Qin H, Geng D. Effect of single nucleotide polymorphisms in the ATP-binding cassette B1 gene on the clinical outcome of traumatic brain injury. GENETICS AND MOLECULAR RESEARCH 2015; 14:10948-53. [PMID: 26400323 DOI: 10.4238/2015.september.21.6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The critical role of ATP-binding cassette B1 (ABCB1) in the function of the blood-brain barrier led us to conducted this prospective study in order to investigate the clinical outcome of patients suffering from severe traumatic brain injury. A total of 182 patients with traumatic brain injury were included in our study. Genotyping of ABCB1 C3435T and G2677T/A was conducted using polymerase chain reaction-restriction fragment length polymorphism. Using multivariate-logistic regression analysis, we found that patients carrying the CT+CC genotype of ABCB1 C3435T were more likely to have a better neurological outcome when compared with the TT genotype (odds ratio = 2.71, 95% confidence interval = 1.12-6.86). However, no significant association was found between the G2677T/A polymorphism and outcome of traumatic brain injury patients. Our study provides important information regarding the prognostic value of ABCB1 C3435T, and the ABCB1 C3435T polymorphism may be used as a predictive marker for the outcome of traumatic brain injury patients.
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Liu X, Zhang W, Geng D, He J, Zhao Y, Yu L. Clinical significance of fibroblast growth factor receptor-3 mutations in bladder cancer: a systematic review and meta-analysis. GENETICS AND MOLECULAR RESEARCH 2014; 13:1109-20. [PMID: 24634132 DOI: 10.4238/2014.february.20.12] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Mutations in the fibroblast growth factor receptor-3 (FGFR3) gene are frequently found in bladder cancer, but their prognostic value remains controversial. To globally summarize the association between FGFR3 mutations and the grade and stage of bladder cancer, and to analyze the predictive role of FGFR3 mutations with respect to survival, eligible studies were identified and assessed for quality through multiple search strategies. Risk ratio (RR) data were collected from studies comparing the number of FGFR3 mutants among low-grade and early-stage bladder cancer patients to the number among high-grade and late-stage patients. Hazard ratio (HR) data were collected from studies comparing survival in patients with mutant FGFR3 genes to those with wild-type genes. Studies were pooled, and the RRs of grade and stage and the HRs of survival were calculated. Thirty studies were included in the present meta-analysis. FGFR3 mutations were found to be closely associated with low-grade and early-stage bladder cancer, showing pooled RRs = 2.948 [95% confidence interval (CI) = 2.357-3.688] and 2.845 (95%CI = 2.145- 3.773), respectively. Notably, patients with FGFR3 mutations tended to show better disease-, progress-, and recurrence-free survival (HR = 0.561, 95%CI = 0.405-0.779), and better disease-specific survival (HR = 0.363, 95%CI = 0.266-0.496). This study demonstrated that FGFR3 mutations are closely related to low grade, early stage, and better survival among bladder cancer patients.
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Zhou F, Lu J, Zhu X, Mao H, Yang H, Geng D, Xu Y. Effects of a Cannabinoid Receptor 2 Selective Antagonist on the Inflammatory Reaction to Titanium Particles In Vivo and In Vitro. J Int Med Res 2010; 38:2023-32. [PMID: 21227006 DOI: 10.1177/147323001003800616] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Wear particle-induced inflammation is a major factor contributing to aseptic loosening in peri-prosthetic tissue. The effects of cannabinoid receptor 2 (CB2) on wear particle-induced inflammation remain unclear. Reverse transcription–polymerase chain reaction and enzyme-linked immunosorbent assay were used to assess the effects of a CB2-selective antagonist, AM630, on regulation of the inflammatory reaction and production of pro-inflammatory cytokines in response to in vitro and in vivo stimulation with titanium particles. In vitro studies, in a model for pre-osteoclast-like cells, demonstrated that AM630 inactivation of CB2 profoundly inhibited interleukin (IL)-1β and tumour necrosis factor (TNF)-α production by RAW264.7 cells stimulated with titanium particles. In vivo findings in a murine air-pouch model of titanium-induced inflammatory osteolysis indicated that AM630 reduced titanium-induced tissue inflammation, seen as a reduction in pouch membrane thickness, inflammatory infiltration and levels of the pro-inflammatory cytokines IL-1β and TNF-α. Thus, inactivation of CB2 by AM630 inhibited the titanium particle-induced inflammatory reaction by reducing pro-inflammatory cytokines in vitro and in vivo.
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Zhang Y, Dong R, Fan H, Li S, Geng D. Hypothalamus syndrome in opticospinal multiple sclerosis. AJNR Am J Neuroradiol 2010; 32:E153-5. [PMID: 21051517 DOI: 10.3174/ajnr.a2278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This study describes a case of a patient with OSMS who presented with somnolence, periodic fever, memory impairment, and amenorrhea. Serum prolactin levels were found to be higher than normal. MR imaging showed a bilateral involvement of the hypothalamus. The clinical presentation, laboratory examination, and MR imaging findings suggested a diagnosis of hypothalamus syndrome in this patient.
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Wu J, Yang H, Qiu Z, Zhang Q, Ding T, Geng D. Effect of combined treatment with methylprednisolone and Nogo-A monoclonal antibody after rat spinal cord injury. J Int Med Res 2010; 38:570-82. [PMID: 20515570 DOI: 10.1177/147323001003800219] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The purpose of this study was to investigate the effects of combination therapy with methylprednisolone (MP) and Nogo-66 antagonistic peptide (NEP1-40) on morphological and functional recovery in adult rats subjected to thoracic compression spinal cord injury (SCI). Animals were randomized into four groups: a trauma control group, an MP group, an NEP1-40 group, and a combined treatment group. The inflammatory reaction, neuronal and oligodendrocyte survival, and ultrastructure were assessed at the injury site. Functional analysis was also performed using Basso, Beattie and Bresnahan (BBB) scoring. Rat behaviour was evaluated regularly up to week 4. NEP1-40 did not alter the beneficial effect of MP on haematogenous inflammatory cell infiltration, while combined treatment resulted in greater neuronal and oligodendrocyte survival compared with monotherapy or control. Combination therapy resulted in better locomotor scores. These results in a clinically-relevant SCI model showed that significant neuroprotection can be obtained by combining an initial acute IV injection of MP with continuously infused NEP1-40.
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Tan WH, Du XY, Liu J, Zhai LB, Wang LX, Geng D. [Effect of a traditional Chinese medicine compound on chronic heart failure in guinea-pigs]. SICHUAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF SICHUAN UNIVERSITY. MEDICAL SCIENCE EDITION 2009; 40:89-92. [PMID: 19292053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE To investigate the effect of a traditional Chinese medicine compound (CTMC) on chronic heart failure (CHF) in guinea-pigs. METHODS The CHF of guinea-pigs were induced by repeated injection of hyodemic isoproterenol. The hemodynamics, organ (heart, lung, liver and kidney)/body weight ratio, pathological changes, and serum cTn-I and CK-MB were measured to determine the effectiveness of the traditional Chinese medicine treatement. RESULTS The LVDP and LVEDP were decreased and the absolute value of + dp/dt(max) and - dp/ dt(max) were increased by the administration of 10 mg/kg, 20 mg/kg and 30 mg/kg of the compound tablets. The effect increased with doses. The traditional Chinese medicine also decreased the area of myocardial necrosis and the degree of injury to myocardiacyte. The intervention group had lower serum cTn-I and CK-MB levels than the controls. CONCLUSION The compound tablets can improve the left ventricular diastolic function of CHF and reduce the myocardial damage in a dose-dependent manner.
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Shi XW, Ren FL, Geng D. [Genetic polymorphism of 15 STR on chromosome 2 and 11 in Shaanxi Han people in China]. ZHONG NAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF CENTRAL SOUTH UNIVERSITY. MEDICAL SCIENCES 2008; 33:587-591. [PMID: 18667770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To investigate the genetic polymorphism of 15 short tandem repeat(STR)loci on chromosome 2 and chromosome 11 in Shaanxi Han people in China. METHODS Fluorescence-based gene scan technique was used to examine the genetic polymorphism of 15 STR loci in 175 unrelated individuals from Chinese Han population in Shannxi province. RESULTS The number of alleles D2S335, D2S396, D2S338, D2S2382, D2S305, D2S151, D2S2368, D2S391,D11S912, D11S4090, D11S4147, D11S4190, D11S4149, D11S4126, and D11S4094 was 11,11,11,10,8,8,9,12 ,7,11,8,10,5,5, and 6. The distribution of allele frequencies of the 15 STR was consistent with Hard-Weinberg equilibrium (P > 0.05). Heterozygosity (H) value was 0.4216 to approximately 0.8517, the average power of discrimination (DP) was 0.6568 to approximately 0.9598, polymorphism information content (PIC) was 0.4078 to approximately 0.8366, and probability of paternity exclusion (EPP) was 0.3135 to approximately 0.8537. CONCLUSION The 15 STR loci have relatively high genetic polymorphism in Shaanxi Han population, which provides the genetic structure of Chinese Han groups, and is also useful in anthropology and forensic science.
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Wang S, Guo X, Tan WH, Geng D, Deng BP, Wang CE, Qu X. Detection of serum proteomic changes and discovery of serum biomarkers for Kashin-Beck disease using surface-enhanced laser desorption ionization mass spectrometry (SELDI-TOF MS). J Bone Miner Metab 2008; 26:385-93. [PMID: 18600406 DOI: 10.1007/s00774-007-0828-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Accepted: 10/30/2007] [Indexed: 11/24/2022]
Abstract
The purpose of the current study was to investigate the changes of serum proteome and discover potential biomarkers for Kashin-Beck disease (KBD) using surface-enhanced laser desorption ionization mass spectrometry (SELDI-TOF MS). The serum protein profiles from 102 cases (36 KBD patients, 16 controls in KBD areas, 33 controls in non-KBD areas, and 17 osteoarthritis controls) were detected by SELDI-TOF MS and weak cation-exchange protein chip. Differently expressed peaks in KBD were identified by comparing the data among the four groups using the nonparametric Mann-Whitney test with Bonferroni correction at a significance level of 0.05. Then, those 102 cases were used to generate a classification tree as the training set, and an additional 34 cases were collected as the test set. A classification tree was generated by Biomarker Patterns Software (Ciphergen). Multiple protein changes were detected in the KBD group, including three potential biomarkers (15 886, 5336, 6113 m/z). A classification tree with three distinct proteins was generated. The classification tree was able to distinguish the KBD patients from the controls with 88.89% specificity and 86.36% sensitivity. The study demonstrates that marked serum proteomic changes exist in KBD. The proteins represented by the differently expressed peaks are candidate biomarkers for KBD.
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Tornetta M, Fisher D, O'Neil K, Geng D, Schantz A, Brigham-Burke M, Lombardo D, Fink D, Knight D, Sweet R, Tsui P. Isolation of human anti-idiotypic antibodies by phage display for clinical immune response assays. J Immunol Methods 2007; 328:34-44. [PMID: 17888945 DOI: 10.1016/j.jim.2007.08.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Revised: 05/23/2007] [Accepted: 08/02/2007] [Indexed: 11/29/2022]
Abstract
The clinical development of therapeutic proteins requires assays that measure the pharmacokinetic (PK) profile of, and the potential immune response (IR) to, the protein agent. Each assay requires reagents that are highly specific for the therapeutic protein. For therapeutic monoclonal antibodies, anti-CDR-specific, or anti-idiotypic (anti-id), antibodies are an ideal class of reagents suitable for these assays because of their high specificity and affinity to the drug antibody. We generated anti-ids to two human antibodies by antibody phage display using the MorphoSys HuCAL GOLD Fab library. To selectively target the CDR regions, serum and a framework-matched mAb were included as competitors during the phage selection process. Panels of CDR-specific Fabs, with low to sub-nM affinities, were isolated against both targets. The CDR specificity of these Fabs was shown by their lack of binding to a framework-matched control mAb and by competition of this binding with the soluble antigens of the respective therapeutic mAb targets. The candidate anti-id Fabs were able to detect both immobilized and soluble target Ab without being affected by serum, a requirement for both PK assay and the IR bridging assay format. Combinations of the Fabs for PK detection assays were identified by pairwise binding studies, although the pair for one target mAb lacks the desired sensitivity for PK assays. To evaluate their potential as anti-drug antibodies (ADAs), the best Fabs for one of the targets were converted and produced as the required bivalent human mAbs. In comparison to rodent mAbs and primate polyclonal serum, the phage display derived human mAbs were equally effective as reference standards. Our results demonstrate that competition-based phage selection can be an effective method for the isolation of anti-idiotypic antibodies for PK and IR assay development, and in this latter case, overcome limitations of current methods using rodent derived anti-ids.
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Ren FL, Guo X, Zhang RJ, Wang SJ, Zuo H, Zhang ZT, Geng D, Yu Y, Su M. Effects of selenium and iodine deficiency on bone, cartilage growth plate and chondrocyte differentiation in two generations of rats. Osteoarthritis Cartilage 2007; 15:1171-7. [PMID: 17490897 DOI: 10.1016/j.joca.2007.03.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Accepted: 03/16/2007] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The purpose of the current study was to investigate the roles of combined selenium and iodine deficiency in bone development as a possible experimental model of Kashin-Beck osteoarthropathy. METHODS Sprague-Dawley rats (n=48) were randomly divided into selenium deficiency (-Se+I), iodine deficiency (+Se-I), combined selenium and iodine deficiency (-Se-I), and selenium and iodine sufficient (+Se+I) groups. Growth of bone and cartilage, and the expression of type X collagen (ColX) and parathyroid hormone-related peptide (PTHrP) were measured in two generations of rats (F(0) and F(1)). RESULTS The tibial length in -Se-I rats was significantly shorter in F(1) generation. In +Se-I of F(1) rats, the thickness of the growth plate cartilage, and the proliferative zone was smaller, while in -Se-I rats the growth plate, and the proliferative and hypertrophic zones were also thinner in F(1) generation. In articular cartilage, ColX expression was increased in the deep zone in -Se-I rats of F(0) generation, and in -Se+I, +Se-I and -Se-I rats of F(1) generation. PTHrP expression was increased in the middle zone of -Se+I, +Se-I and -Se-I rats of both F(0) and F(1) generations. In the growth plate cartilage, ColX and PTHrP were expressed in the hypertrophic zone. ColX expression was significantly weaker in -Se+I and -Se-I rats in both F(0) and F(1) generations, while PTHrP expression was stronger in -Se+I, +Se-I and -Se-I rats in both F(0) and F(1) animals. CONCLUSIONS Combined selenium and iodine deficiency impaired the growth of bone and cartilage. The changes in the expression of ColX and PTHrP induced by combined selenium and iodine deficiency were compatible to measurements of ColX and PTHrP in Kashin-Beck osteoarthropathy.
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Lei YX, Zhao JJ, Hu AL, Li GY, Zhang DY, Zhao J, Geng D, Guo X. [Organic gallium improves tretinoin-induced osteoporosis in rats]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2007; 27:1361-4. [PMID: 17884779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
OBJECTIVE To investigate the effect of organic gallium and gallium chloride on bone metabolism and their therapeutic effect against tretinoin-induced osteoporosis in rats. METHODS Rat models of osteoporosis was established with intragastric administration of tretinoin at the daily dose of 85 mg/kg for 15 days and randomized into control, organic gallium and gallium chloride groups. After administration of the corresponding treatments (none for the control group) for 4 weeks, the changes of the indices for osteoporosis were evaluated through biochemical and pathological approaches. RESULTS Tretinoin induced obvious changes in bone structure and contents of bone calcium and other elements, causing also significantly increased tartrate-resistant acid phosphatase (TRAP) and alkaline phosphatase (AKP), which suggested the development of osteoporosis. Administration of organic gallium and gallium chloride treatments increased the bone density, bone cortex thickness and the percentage of bone trabecula, and Ga, Ca, P contents in the femur and teeth, but lowered the activity of TRAP and AKP, suggesting decreased bone conversion rate. Compared with gallium chloride, organic gallium required smaller dose with better safety to produce better therapeutic effect. CONCLUSION Organic gallium can be safe and effective for treatment of tretinoin-induced osteoporosis in rats.
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Li XY, Guo X, Wang LX, Geng D, Kang LL, Wang S, Wang ZF, Gu QS. [Serum hyaluronic acid, tumor necrosis factor -alpha, vascular endothelial growth factor, NO, and Se levels in adult patients with Kashin-Beck disease]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2007; 27:941-4. [PMID: 17666321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
OBJECTIVE To investigate the association of serum levels of hyaluronic acid (HA), tumor necrosis factor-alpha (TNF-alpha), vascular endothelial growth factor (VEGF), NO, and Se with the clinical manifestations in adult patients with Kashin-Beck disease (KBD). METHODS Total 216 adults were selected for KBD screening from the KBD-prevalent areas in Yongshou county and the non-KBD areas of Chang'an county, Xi'an city, ShaanXi Province. According to the National Diagnostic Criteria of Kashin-Beck Disease in China, the diagnoses of KBD was established in 25 adult patients (11 men and 14 women, average age of 47.88+/-11.16 years), and 20 healthy control subjects from the KBD areas (8 men and 12 women, average age of 47.85+/-12.05 years) and 20 from the non-KBD areas (8 men and 12 women, average age of 47.45+/-11.24 years) were also selected to serve as controls. There was no significant difference in the average age and gender distribution between the 3 groups. The serum levels of HA, TNF-alpha, VEGF, NO and Se were measured by enzyme-linked immunosorbent assay, nitrate reductase method and griphite furnace atomic absorption spectrometry. RESULTS Serum NO level was significantly higher in KBD group (41.7+/-21.89 micromol/L) than in the health controls from KBD areas (17.1+/-13.01 micromol/L) and non-KBD areas (17.58+/-11.48 micromol/l, F=13.11, df=2, P<0.001). Serum TNF-alpha level in KBD group (32.7+/-3.55 pg/ml) was significantly higher than that in the control subjects from the non-KBD areas (30.95+/-2.22 pg/ml, F=3.672, df=2, P=0.031), but similar with the control subjects from the KBD areas (32.7+/-3.55 pg/ml). Serum TNF-alpha and NO levels were identified as the indices that differed between adult KBD patients and the controls from both KBD and non-KBD areas by differential analysis (the function of differentiation was 0.062xNO+0.173xTNF -7.218). CONCLUSION Serum TNF-alpha and NO levels are significantly increased in adult KBD patients and are associated with the clinical manifestations of KBD.
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Wang SJ, Guo X, Ren FL, Zhang YG, Zhang ZT, Zhang FJ, Geng D. [Comparison of apoptosis of articular chondrocytes in the pathogenesis of Kashin-beck disease and primary osteoarthritis]. ZHONGGUO YI XUE KE XUE YUAN XUE BAO. ACTA ACADEMIAE MEDICINAE SINICAE 2006; 28:267-70. [PMID: 16733918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
OBJECTIVE To investigate chondrocyte apoptosis and expression of Fas and inducible nitric oxide synthase (iNOS) in articular cartilage in the pathogenesis of Kashin-beck disease (KBD) and primary osteoarthritis (OA). METHODS The collected samples of articular cartilage were divided into three groups: normal control (15 cases), KBD adults (15 cases) and OA (15 cases). Chondrocyte apoptosis was detected by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling method, and Fas and iNOS in articular cartilage were stained by immunohistochemistry. RESULTS The positive percentages of chondrocyte apoptosis stained in articular cartilage of KBD and OA were significantly higher than that of the control (P < 0.01), and the positive percentage of chondrocytes apoptosis in the eroded areas of articular cartilage were significantly higher than in the non-eroded areas in articular cartilage of the same patient with KBD and OA (P < 0.05). There was no significant difference in positive percentage of chondrocytes apoptosis between KBD and OA. The positive percentages of Fas and iNOS in chondrocytes were significantly higher in KBD and OA than in control (P < 0.01). Significant differences in Fas and iNOS expression between the eroded areas and non-eroded areas were seen in articular cartilage of patients with KBD and OA (P < 0.05), but such difference did not exist between KBD and OA. CONCLUSION Cell apoptosis seems to be associated with the pathogenesis of both KBD and OA. Fas and iNOS might mediate chondrocyte apoptosis.
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Zuo H, Guo X, Kang LL, Ping ZG, Zhang BD, Wang SJ, Lai JH, Geng D. [Analysis of allele frequencies of 6 short tandem repeat loci on chromosome 12 in patients with Kashing-Beck disease]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2006; 26:414-7. [PMID: 16624740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
OBJECTIVE To analyze the allele frequencies of 6 STR loci (D12S358, D12S1675, D12S1663, D12S1697, D12S16725 and D12S1613) on chromosome 12 among KBD patients and residents in the KBD and non-KBD areas. METHODS EDTA-blood samples were collected from 146 unrelated Chinese Han individuals in Shaanxi Province including 57 KBD patients, 48 control subjects living in the Kashing-Beck disease(KBD) area and 48 in the non-KBD area. The DNA samples were extracted and amplified by PCR, and the PCR products were analyzed by ABI 3100 Genetic Analyzer. RESULTS In KBD patients, the allele number for the 6 STR loci (D12S358, D12S1675, D12S1663, D12S1697, D12S16725 and D12S1613) was 7, 7, 7, 10, 12 and 8, and the genotype number were 13, 12, 9, 17, 19 and 10, respectively; in the residents in KBD area, the allele number was 7, 5, 7, 9, 13 and 9, and the genotype number 12, 10, 12, 19, 16 and 8; in residents in non-KBD area, the allele number was 7, 5, 5, 12, 8 and 9, and the genotype number 17, 16, 8, 22, 14 and 8. There were significant differences in the allele frequencies in the D12S1725 loci between KBD patients and residents living in KBD area (P=0.0119) and the non-KBD area (P=0.0050), but no significant difference in other 5 loci among the 3 groups. CONCLUSION KBD patients have significantly different allele distribution patterns in the D12S1725 loci from the control subjects.
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Wang SJ, Guo X, Zuo H, Zhang YG, Xu P, Ping ZG, Zhang Z, Geng D. Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. J Rheumatol 2006; 33:615-9. [PMID: 16511931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
OBJECTIVE Kashin-Beck disease (KBD) is a chronic, endemic osteochondropathy principally occurring in children. We investigated apoptotic chondrocyte death and the expression of Bcl-2, Bax, Fas, and inducible nitric oxide synthase (iNOS) in articular cartilage from patients with KBD in order to determine the pathogenesis of chondronecrosis in KBD. METHODS Samples of articular cartilage were divided into 2 groups: control children (15 samples from 15 cases), and children with KBD (15 samples from 15 cases). KBD patients were diagnosed according to "Pathological Criteria to Diagnose KBD in China." Chondrocyte apoptosis was detected by TUNEL staining, and Bcl-2, Bax, Fas, and iNOS-positive articular chondrocytes were stained by immunohistochemistry. Articular cartilage was classified in 3 zones, and positive findings were counted by light microscopy for cytoplasmic staining by polyclonal antibodies of Bcl-2, Bax, Fas, and iNOS and apoptotic chondrocytes by TUNEL. RESULTS The percentage of positive apoptotic chondrocytes stained by TUNEL in the middle zone of articular cartilage from the KBD patient group (33.60% +/- 2.71%) was higher than that of controls (1.33% +/- 0.41%; p < 0.01). The percentages of chondrocytes staining for Bcl-2, Bax, Fas, and iNOS in KBD patients were significantly higher than in controls (p < 0.01); the remarkable difference in Bcl-2, Bax, Fas, and iNOS expression among the upper, middle, and deep cartilage zones was also seen in KBD articular cartilage (p < 0.01); and staining for Bcl-2, Bax, Fas, and iNOS in KBD patients was prominent in the upper zone (41.93% +/- 12.26%, 45.60% +/- 15.78%, 53.60% +/- 16.49%, 45.47% +/- 14.02%, respectively) and the middle zone (14.93% +/- 3.50%, 13.87% +/- 4.32%, 23.27% +/- 4.83%, 21.67% +/- 6.82%) of articular cartilage. CONCLUSION The apoptotic chondrocytes and Bcl-2, Bax, Fas, and iNOS-positive chondrocytes were significantly more numerous in patients with KBD than in controls.
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Guo X, Zuo H, Cao CX, Zhang Y, Geng D, Zhang ZT, Zhang YG, von der Mark K, von der Mark H. Abnormal expression of Col X, PTHrP, TGF-beta, bFGF, and VEGF in cartilage with Kashin-Beck disease. J Bone Miner Metab 2006; 24:319-28. [PMID: 16816927 DOI: 10.1007/s00774-006-0690-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2005] [Accepted: 02/08/2006] [Indexed: 10/24/2022]
Abstract
The purpose of the current study was to investigate the abnormal expression of Col X, PTHrP, TGF-beta, bFGF, and VEGF in cartilage from patients with Kashin-Beck disease (KBD) to understand the pathogenesis of chondronecrosis in KBD. Articular cartilage and growth plate cartilage collected were divided into four groups: control children (8 samples, 5 cases), KBD children (19 samples, 9 cases), control adults (8 samples, 6 cases), and KBD adults (16 samples, 15 cases). The presence of PTHrP, TGF-beta1, bFGF, VEGF, and collagen X in articular cartilage and in growth plate cartilage was analyzed by immunohistochemistry. Articular cartilage and growth plate were each divided in three zones, and the rate of positive cells was counted by light microscope for cytoplasmic and pericellular staining. Results showed that (1) in KBD children, Col X expression was lower in the deep zone of growth plate cartilage than in normal children; in articular cartilage of KBD adults, however, collagen X expression was higher in the middle zone compared to the controls; (2) staining for bFGF, PTHrP, TGF-beta1, and VEGF in KBD adult patients was prominent in the chondrocyte clusters and the eroded surface of articular cartilage, and the percentage of chondrocyte staining was significantly higher than in control samples (t = 3.64-10.34, df = 12 for children and 19 for adults, P = 0.002-0.0001); and (3) the enhanced PTHrP, TGF-beta1, and VEGF staining in the deep and middle zone of KBD articular cartilage correlated with the high incidence of chondronecrosis in the middle zone (48.5% +/- 10.2%) and deep zone (70.6% +/- 27.0%) of adult KBD cartilage. In conclusion, Col X expression was reduced in areas of chondrocyte necrosis in the deep zone of KBD articular cartilage, indicating changes in terminal chondrocyte differentiation. PTHrP, TGF-beta1, and VEGF expression was significantly altered and indicated degenerative changes in KBD cartilage, which initially resemble those occurring in osteoarthritis, but lead eventually to chondronecrosis, an event not observed in osteoarthritis.
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Kang LL, Guo X, Ping ZG, Zuo H, Lai JH, Zhang BD, Geng D, Chen T. [Analysis of genetic polymorphism of 7 STR loci on chromosome 12 in Shaanxi Han populations]. YI CHUAN = HEREDITAS 2005; 27:869-72. [PMID: 16378930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
To analyze the genetic polymorphism of 7 STR loci (D12S1718,D12S1675, D12S358, D12S367, D12S1638, D12S1646 and D12S1682) on chromosome 12 in Shaanxi Hans. EDTA-blood specimens were collected from 80 unrelated individuals from Chinese Han population in Shaanxi province. The DNA samples were extracted and relevant fragments were amplified by polymerase chain reaction (PCR). The PCR products were analyzed by ABI 3100 Genetic Analyzer. The number of alleles and genotypes observed at loci D12S1718, D12S1675, D12S358, D12S367, D12S1638, D12S1646 and D12S1682 were 7, 10, 8, 8, 6, 9, 11 for alleles and 10, 17, 18, 18, 14, 18, and 26 for genotypes, respectively. The heterozygosities for the 7 STR loci were 44.28%, 66.10%, 78.89%, 77.89%, 73.69%, 74.55% and 82.39%, respectively. The distribution of allele frequencies of 7 STR loci on chromosome 12 was consistent with Hardy-Weinberg equilibrium and relatively high genetic polymorphism was observed in Shaanxi Han population.
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Marshall DJ, San Mateo LR, Rudnick KA, McCarthy SG, Harris MC, McCauley C, Schantz A, Geng D, Cawood P, Snyder LA. Induction of Th1-type immunity and tumor protection with a prostate-specific antigen DNA vaccine. Cancer Immunol Immunother 2005; 54:1082-94. [PMID: 16047142 PMCID: PMC11034269 DOI: 10.1007/s00262-005-0687-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2004] [Accepted: 02/14/2005] [Indexed: 01/19/2023]
Abstract
Prostate specific antigen (PSA) is a serum marker that is widely used in the detection and monitoring of prostate cancer. Though PSA is a self-antigen, T cell responses to PSA epitopes have been detected in healthy men and prostate cancer patients, suggesting it may be used as a target for active immunotherapy of prostate cancer. A PSA DNA vaccine (pPSA) was evaluated in mice and monkeys for its ability to induce antigen-specific immune responses. Mice immunized intradermally with pPSA demonstrated strong PSA-specific humoral and cellular immunity. The anti-PSA immune responses were skewed toward Th1, as shown by high IFNgamma and IL-2 production. The immune response was sufficient to protect mice from challenge with PSA-expressing tumor cells. Tumor protection was durable in the absence of additional vaccination, as demonstrated by protection of vaccinated mice from tumor rechallenge. Furthermore, pPSA vaccination induced PSA-specific antibody titers in male cynomolgus monkeys, which express a closely related PSA gene. These results demonstrate that vaccination with pPSA may be able to break tolerance and can induce an immune response that mediates tumor protection.
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Kang LL, Guo X, Zuo H, Ping ZG, Zhang BD, Lai J, Geng D. [Analysis on allele frequencies of 7 short tandem repeat loci of Kashing-Beck disease patients on]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2005; 26:790-3. [PMID: 16536306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
OBJECTIVE To analyze the allele frequencies of 7 short tandem repeat (STR) loci (D12S1718, D12S1675, D12S358, D12S367, D12S1638, D12S1646 and D12S1682) on chromosome 12 among Kashing-Beck disease (KBD) patients and the control population living in the KBD areas and non-KBD area. METHODS EDTA-blood specimens were collected from 102 unrelated individuals of Chinese Han population in Shaanxi province including 29 KBD patients,30 controls living in the KBD area and 43 living in the non-KBD area. DNA samples were extracted using the Wizard Genomic DNA purification kit (http://www. Promega. com) and were amplified by polymerase chain reaction (PCR) technique. The PCR products were analyzed by ABI 3100 Genetic Analyzer. RESULTS (1) In KBD patients group, the allele number for 7 STR loci were 4,7,7,8,5,5 and 7, the genotype number were 5,12,13,11,10,9 and 13; (2) In the control population living in KBD area, the allele number for 7 STR loci were 4,9,7,6,6,6 and 8,t he genotype number were 5,10,12,14,12,9 and 13;(3) In the control population living in the non-KBD area, the allele number for 7 STR loci were 7,9,7,7,5,8 and 11, the genotype number were 9,16, 17,16,12,15 and 20;(4) Compared with the allele frequencies among three groups, there were significant differences between KBD patients and the controls living in the KBD area (D12S367: P = 0.034; D12S1638: P = 0.041) and the controls living in the non-KBD area (D12S367: P = 0. 029; D12S1638: P= 0 .028) in the D12S367 and D12S1638 loci; (5) There were significant differences among KBD patients (P = 0.036), controls living in the KBD area (P = 0.039) and controls living in the non-KBD area in the D12S1646. CONCLUSION There was significant difference between KBD patients and the controls in the D12S367 and D12S1638 loci.
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Geng D, Shankar G, Schantz A, Rajadhyaksha M, Davis H, Wagner C. Validation of immunoassays used to assess immunogenicity to therapeutic monoclonal antibodies. J Pharm Biomed Anal 2005; 39:364-75. [PMID: 15963677 DOI: 10.1016/j.jpba.2005.04.045] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2004] [Revised: 03/29/2005] [Accepted: 04/01/2005] [Indexed: 10/25/2022]
Abstract
Immunogenicity has always been an important consideration in the evaluation of pharmaceutical protein biologics. In this article, method validation parameters relevant to enzyme immunoassays are described for assays applied to the analysis of anti-drug antibodies, with special considerations for immunogenicity to therapeutic monoclonal antibodies. Common strategies for experimental investigation of various validation parameters are proposed. In addition, a novel, yet simple, approach is proposed to categorize the validation effort into two mutually interdependent phases, based on the characterization of validation parameters as "system descriptive" or "system controlled". System descriptive parameters are those that must be characterized but need not have pre-specified acceptance criteria for assay validation. In contrast, system-controlled parameters should be understood early in assay development, and optimized and confirmed using a priori acceptance criteria in validation to assure sufficient control over them during routine bioanalysis. This approach not only streamlines the validation process but also eliminates unnecessary redundancies. This validation method can be achieved with proper scientific rigor and remain within the realm of GLP compliance. The authors hope that other research groups would engage in discussions on validation of anti-drug antibody assays in order to establish a consistent approach across the industry and academia.
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Wang SJ, Guo X, Zuo H, Zhang YG, Xu P, Ping ZG, Zhang ZT, Geng D. [Chondrocyte apoptosis and the expression of Bcl-2, Bax, Fas and iNos in articular cartilage in Kashin-Beck disease]. DI 1 JUN YI DA XUE XUE BAO = ACADEMIC JOURNAL OF THE FIRST MEDICAL COLLEGE OF PLA 2005; 25:643-6. [PMID: 15958298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
OBJECTIVE To investigate the characteristics of chondrocyte apoptosis and distribution of Bcl-2, Bax, Fas and iNos expressions in articular cartilage in Kashin-Beck disease (KBD). METHODS Samples of articular cartilage were collected from 15 healthy children and 15 children with KBD diagnosed according to the Pathological Criteria of KBD Diagnosis in China. Chondrocyte apoptosis was detected by TUNEL method, and the articular chondrocytes positive for Bcl-2, Bax, Fas and iNos were stained by B-SA immunohistochemistry. RESULTS The percentage of apoptotic chondrocytes positively stained by TUNEL in the middle layer of articular cartilage was significantly higher in KBD children than in the control group (33.60%+/-2.71% vs 1.33%+/-0.41%, t=11.59, P<0.01). Significant difference in Bcl-2, Bax, Fas and iNos expressions was observed between the upper, middle and deep layers of the articular cartilage of KBD children (F =73.49-114.42, P<0.01), and staining for Bcl-2, Bax, Fas and iNos in KBD children was prominent in the upper layer (41.93%+/-12.26%, 45.60%+/-15.78%, 53.60%+/-16.49%, and 45.47%+/-14.02%, respectively) and the middle layer (14.93%+/-3.50%, 13.87%+/-4.32%, 23.27%+/-4.83%, and 21.67%+/-6.82%, respectively) of the articular cartilage; the percentages of chondrocytes positively stained for Bcl-2, Bax, Fas and iNos were significantly higher than those of the control group (t=11.75-18.65, P<0.01). CONCLUSION The percentages of apoptotic chondrocytes and chondrocytes positive for Bcl-2, Bax, Fas and iNos in the articular cartilage of children with KBD are significantly higher than those in healthy children.
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Yu Q, Ma L, Jing S, Xu Y, Geng D. [Clinic significance of nm23, collage IV and PCNA expression in non-small cell lung cancer]. ZHONGGUO FEI AI ZA ZHI = CHINESE JOURNAL OF LUNG CANCER 2001; 4:469-70. [PMID: 21106162 DOI: 10.3779/j.issn.1009-3419.2001.06.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND To study the significance of nm23, collagen IV and PCNA expressions in non-small cell lung cancer. METHODS Expressions of the nm23, collagen IV and PCNA in 84 cases of non-small cell lung cancer were examined with SP immunohistochemical technique. Of the 84 cases, there were squamous cell carcinoma 42, adenocarcinoma 42, stage I 27, stage II 24, stage III 24, and stage IV 9. Statistical analysis was performed with Chi-Square test. RESULTS Expressions of the nm23, collagen IV and PCNA in 84 cases of non-small cell lung cancer were 60. 7% ( 51/ 84) , 75. 0% ( 63/ 84) and 53. 6% ( 45/ 84) respectively. There was negative correlation between the lymph node metastasis and the expressions of nm23 and collagen IV in squamous cell carcinoma, and the expressions of collagen IV and PCNA were associated with tumor differentiation. No correlation was found between TNM stage and expressions of nm23, collagen IV and PCNA. CONCLUSIONS The results indicate that nm23, collagen IV and PCNA participate the modulation of metastasis of non-small cell lung cancer and that they may be used to evaluate the potential of metastasis.
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Lee RS, Yamada K, Womer KL, Pillsbury EP, Allison KS, Marolewski AE, Geng D, Thall AD, Arn JS, Sachs DH, Sayegh MH, Madsen JC. Blockade of CD28-B7, but not CD40-CD154, prevents costimulation of allogeneic porcine and xenogeneic human anti-porcine T cell responses. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:3434-44. [PMID: 10706740 DOI: 10.4049/jimmunol.164.6.3434] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Despite increasing use of swine in transplantation research, the ability to block costimulation of allogeneic T cell responses has not been demonstrated in swine, and the effects of costimulatory blockade on xenogeneic human anti-porcine T cell responses are also not clear. We have compared the in vitro effects of anti-human CD154 mAb and human CTLA4IgG4 on allogeneic pig T cell responses and xenogeneic human anti-pig T cell responses. Both anti-CD154 mAb and CTLA4IgG4 cross-reacted on pig cells. While anti-CD154 mAb and CTLA4IgG4 both inhibited the primary allogeneic pig MLRs, CTLA4IgG4 (7.88 microg/ml) was considerably more inhibitory than anti-CD154 mAb (100 microg/ml) at optimal doses. Anti-CD154 mAb inhibited the production of IFN-gamma by 75%, but did not inhibit IL-10 production, while CTLA4IgG4 completely inhibited the production of both IFN-gamma and IL-10. In secondary allogeneic pig MLRs, CTLA4IgG4, but not anti-CD154 mAb, induced Ag-specific T cell anergy. CTLAIgG4 completely blocked the indirect pathway of allorecognition, while anti-CD154 mAb blocked the indirect response by approximately 50%. The generation of porcine CTLs was inhibited by CTLA4IgG4, but not by anti-CD154 mAb. Human anti-porcine xenogeneic MLRs were blocked by CTLA4IgG4, but only minimally by anti-CD154 mAb. Finally, CTLA4IgG4 prevented secondary xenogeneic human anti-porcine T cell responses. These data indicate that blockade of the B7-CD28 pathway was more effective than blockade of the CD40-CD154 pathway in inhibiting allogeneic pig T cell responses and xenogeneic human anti-pig T cell responses in vitro. These findings have implications for inhibiting cell-mediated immune responses in pig-to-human xenotransplantation.
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MESH Headings
- Abatacept
- Amino Acid Sequence
- Animals
- Antibodies, Blocking/analysis
- Antibodies, Blocking/pharmacology
- Antigens, CD
- Antigens, Differentiation/immunology
- Antigens, Heterophile/immunology
- B7-1 Antigen/immunology
- CD28 Antigens/immunology
- CD40 Antigens/immunology
- CD40 Ligand
- CTLA-4 Antigen
- Cells, Cultured
- Clonal Anergy/immunology
- Cytotoxicity, Immunologic/immunology
- Humans
- Immunoconjugates
- Immunoglobulin G/analysis
- Immunoglobulin G/pharmacology
- Immunosuppressive Agents/pharmacology
- Interferon-gamma/antagonists & inhibitors
- Interferon-gamma/biosynthesis
- Interleukin-10/antagonists & inhibitors
- Interleukin-10/biosynthesis
- Isoantigens/immunology
- Lymphocyte Activation/immunology
- Lymphocyte Culture Test, Mixed
- Membrane Glycoproteins/antagonists & inhibitors
- Membrane Glycoproteins/immunology
- Molecular Sequence Data
- Swine
- Swine, Miniature
- T-Lymphocytes, Cytotoxic/immunology
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Zhou L, Song Y, Geng D. [The reconstruction of laryngeal function in subtotal laryngectomy with preservation of arytenoid cartilage]. ZHONGHUA ER BI YAN HOU KE ZA ZHI 1999; 34:309-10. [PMID: 12764833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
OBJECTIVE To evaluate subtotal laryngectomy with preservation of arytenoid cartilage to reconstruct laryngeal function in T3 glottic or supraglottic laryngeal cancer. METHODS Subtotal laryngectomy with preservation of arytenoid cartilage to reconstruct laryngeal function was reviewed in 20 patients with T3 laryngeal cancer(3 cases with glottic cancer and 17 cases with supraglottic cancer). Recurrent laryngeal nerve was preserved during surgery. The mucous membranes between cricoid cartilage and pharynx were sewed up accordingly. RESULTS All patients had restored phonation and swallowing functions. The 3- and 5-year survival rates were 94.1% and 91.8% respectively. Decannulation rate was 95.0%. CONCLUSION Subtotal laryngectomy with preservation of arytenoid cartilage is recommended for T3 laryngeal cancer.
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Geng D, Baker DP, Foley SF, Zhou C, Stieglitz K, Roberts MF. A 20-kDa domain is required for phosphatidic acid-induced allosteric activation of phospholipase D from Streptomyces chromofuscus. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1430:234-44. [PMID: 10082951 DOI: 10.1016/s0167-4838(99)00005-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Two phospholipase D (PLD) enzymes with both hydrolase and transferase activities were isolated from Streptomyces chromofuscus. There were substantial differences in the kinetic properties of the two PLD enzymes towards monomeric, micellar, and vesicle substrates. The most striking difference was that the higher molecular weight enzyme (PLD57 approximately 57 kDa) could be activated allosterically with a low mole fraction of phosphatidic acid (PA) incorporated into a PC bilayer (Geng et al., J. Biol. Chem. 273 (1998) 12195-12202). PLD42/20, a tightly associated complex of two peptides, one of 42 kDa and the other 20 kDa, had a 4-6-fold higher Vmax toward PC substrates than PLD57 and was not activated by PA. N-Terminal sequencing of both enzymes indicated that both components of PLD42/20 were cleavage products of PLD57. The larger component included the N-terminal segment of PLD57 and contained the active site. The N-terminus of the smaller peptide corresponded to the C-terminal region of PLD57; this peptide had no PLD activity by itself. Increasing the pH of PLD42/20 to 8.9, followed by chromatography of PLD42/20 on a HiTrap Q column at pH 8.5 separated the 42- and 20-kDa proteins. The 42-kDa complex had about the same specific activity with or without the 20-kDa fragment. The lack of PA activation for the 42-kDa protein and for PLD42/20 indicates that an intact C-terminal region of PLD57 is necessary for activation by PA. Furthermore, the mechanism for transmission of the allosteric signal requires an intact PLD57.
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