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Li Z, Li Y, Chakraborty M, Fan Y, Bui HH, Peake DA, Kuo MS, Xiao X, Cao G, Jiang XC. Liver-specific deficiency of serine palmitoyltransferase subunit 2 decreases plasma sphingomyelin and increases apolipoprotein E levels. J Biol Chem 2009; 284:27010-9. [PMID: 19648608 DOI: 10.1074/jbc.m109.042028] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Sphingomyelin (SM) is one of the major lipid components of plasma lipoproteins. Serine palmitoyltransferase (SPT) is the key enzyme in SM biosynthesis. Mice totally lacking in SPT are embryonic lethal. The liver is the major site for plasma lipoprotein biosynthesis, secretion, and degradation, and in this study we utilized a liver-specific knock-out approach for evaluating liver SPT activity and also its role in plasma SM and lipoprotein metabolism. We found that a deficiency of liver-specific Sptlc2 (a subunit of SPT) decreased liver SPT protein mass and activity by 95 and 92%, respectively, but had no effect on other tissues. Liver Sptlc2 deficiency decreased plasma SM levels (in both high density lipoprotein and non-high density lipoprotein fractions) by 36 and 35% (p < 0.01), respectively, and increased phosphatidylcholine levels by 19% (p < 0.05), thus increasing the phosphatidylcholine/SM ratio by 77% (p < 0.001), compared with controls. This deficiency also decreased SM levels in the liver by 38% (p < 0.01) and in the hepatocyte plasma membranes (based on a lysenin-mediated cell lysis assay). Liver-specific Sptlc2 deficiency significantly increased hepatocyte apoE secretion and thus increased plasma apoE levels 3.5-fold (p < 0.0001). Furthermore, plasma from Sptlc2 knock-out mice had a significantly stronger potential for promoting cholesterol efflux from macrophages than from wild-type mice (p < 0.01) because of a greater amount of apoE in the circulation. As a result of these findings, we believe that the ability to control liver SPT activity could result in regulation of lipoprotein metabolism and might have an impact on the development of atherosclerosis.
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Liu J, Huan C, Chakraborty M, Zhang H, Lu D, Kuo MS, Cao G, Jiang XC. Macrophage sphingomyelin synthase 2 deficiency decreases atherosclerosis in mice. Circ Res 2009; 105:295-303. [PMID: 19590047 DOI: 10.1161/circresaha.109.194613] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE Sphingomyelin synthase (SMS)2 contributes to de novo sphingomyelin (SM) biosynthesis and plasma membrane SM levels. SMS2 deficiency in macrophages diminishes nuclear factor kappaB and mitogen-activated protein kinase activation induced by inflammatory stimuli. OBJECTIVE The effects of SMS2 deficiency on the development of atherosclerosis are investigated. METHODS AND RESULTS We measured cholesterol efflux from macrophages of wild-type (WT) and SMS2 knockout (KO) mice. We transplanted SMS2 KO mouse bone marrow into low-density lipoprotein (LDL) receptor (LDLr) knockout mice (SMS2(-/-)-->LDLr(-/-)), creating a mouse model of SMS2 deficiency in the macrophages. We found that SMS2 deficiency caused significant induction of cholesterol efflux in vitro and in vivo. Moreover, we found that SMS2 KO mice had less interleukin-6 and tumor necrosis factor alpha in the circulation before and after endotoxin stimulation, compared with controls. More importantly, after 3 months on a western-type diet, SMS2(-/-)-->LDLr(-/-) mice showed decreased atherosclerotic lesions in the aortic arch, root (57%, P<0.001), and the entire aorta (42%, P<0.01), compared with WT-->LDLr(-/-) mice. Analysis of plaque morphology revealed that SMS2(-/-)-->LDLr(-/-) mice had significantly less necrotic core area (71%, P<0.001), less macrophage content (37%, P<0.01), and more collagen content (35%, P<0.05) in atherosclerotic lesions. We also found that SMS2(-/-)-->LDLr(-/-) mice had significantly lower free cholesterol and cholesteryl ester levels in the brachiocephalic artery than WT-->LDLr(-/-) mice (33 and 52%, P<0.01 and P<0.001, respectively). CONCLUSIONS SMS2 deficiency in the macrophages reduces atherosclerosis in mice. Macrophage SMS2 is thus a potential therapeutic target for treatment of this disease.
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Modhera B, Chakraborty M, Parikh PA, Jasra RV. Synthesis of nano-crystalline zeolite β: Effects of crystallization parameters. CRYSTAL RESEARCH AND TECHNOLOGY 2009. [DOI: 10.1002/crat.200800474] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Liu J, Zhang H, Li Z, Hailemariam TK, Chakraborty M, Jiang K, Qiu D, Bui HH, Peake DA, Kuo MS, Wadgaonkar R, Cao G, Jiang XC. Sphingomyelin synthase 2 is one of the determinants for plasma and liver sphingomyelin levels in mice. Arterioscler Thromb Vasc Biol 2009; 29:850-6. [PMID: 19286635 DOI: 10.1161/atvbaha.109.185223] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND It has been proposed that plasma sphingomyelin (SM) plays a very important role in plasma lipoprotein metabolism and atherosclerosis. Sphingomyelin synthase (SMS) is the last enzyme for SM de novo biosynthesis. Two SMS genes, SMS1 and SMS2, have been cloned and characterized. METHODS AND RESULTS To evaluate the in vivo role of SMS2 in SM metabolism, we prepared SMS2 knockout (KO) and SMS2 liver-specific transgenic (LTg) mice and studied their plasma SM and lipoprotein metabolism. On a chow diet, SMS2 KO mice showed a significant decrease in plasma SM levels (25%, P<0.05), but no significant changes in total cholesterol, total phospholipids, or triglyceride, compared with wild-type (WT) littermates. On a high-fat diet, SMS2 KO mice showed a decrease in plasma SM levels (28%, P<0.01), whereas SMS2LTg mice showed a significant increase in those levels (29%, P<0.05), but no significant changes in other lipids, compared with WT littermates. Atherogenic lipoproteins from SMS2LTg mice displayed a significantly stronger tendency toward aggregation after mammalian sphingomyelinase treatment, compared with controls. Moreover, SMS2 deficiency significantly increased plasma apoE levels (2.0-fold, P<0.001), whereas liver-specific SMS2 overexpression significantly decreased those levels (1.8-fold, P<0.01). Finally, SMS2 KO mouse plasma promoted cholesterol efflux from macrophages, whereas SMS2LTg mouse plasma prevented it. CONCLUSIONS We therefore believe that regulation of liver SMS2 activity could become a promising treatment for atherosclerosis.
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Joardar GK, Chatterjee C, Sadhukhan SK, Chakraborty M, Dass P, mandal A. Needle sticks injury among nurses involved in patient care: a study in two medical college hospitals of West Bengal. Indian J Public Health 2008; 52:150-152. [PMID: 19189838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
A hospital-based retrospective study on a sample of 228 nurses involved in patient care, in two medical college hospitals of West Bengal, showed that 61.4% of them sustained at least one Needle Stick Injury (NSI) in last 12 months. The risk of such injuries per 1000 nurses per year was found to be 3,280. Out of the most recent injuries among 140 nurses, 92.9% remained unreported to appropriate authorities; in 52.9% events hand gloves were worn by the nurses; only 5% of those nurses received hepatitis B vaccine, 2.1% hepatitis B immunoglobulin and none of them received post exposure prophylaxis for HIV.
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Chatterjee C, Joardar GK, Mukherjee G, Chakraborty M. Septic abortions: a descriptive study in a teaching hospital at North Bengal, Darjeeling. Indian J Public Health 2007; 51:193-194. [PMID: 18229444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
A hospital based cross sectional study for one year done among 57 diagnosed and admitted septic abortion cases, revealed that 71.9% septic abortions were performed by untrained persons, 63.2% mothers were illiterate, 22.8% mothers were in adolescent age group. Exploratory Laparotomy was needed in 46.3% cases and important complications for referring were severe anaemia and septic shock.
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Mullin JW, Chakraborty M, Mehta K. Nucleation and growth of ammonium sulphate crystals from aqueous solution. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/jctb.5010201202] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Mullin JW, Amatavivadhana A, Chakraborty M. Crystal habit modification studies with ammonium and potassium dihydrogen phosphate. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/jctb.5010200503] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Sehgal D, Thomas S, Chakraborty M, Jameel S. Expression and processing of the Hepatitis E virus ORF1 nonstructural polyprotein. Virol J 2006; 3:38. [PMID: 16725054 PMCID: PMC1481634 DOI: 10.1186/1743-422x-3-38] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Accepted: 05/26/2006] [Indexed: 01/17/2023] Open
Abstract
Background The ORF1 of hepatitis E virus (HEV) encodes a nonstructural polyprotein of ~186 kDa that has putative domains for four enzymes: a methyltransferase, a papain-like cysteine protease, a RNA helicase and a RNA dependent RNA polymerase. In the absence of a culture system for HEV, the ORF1 expressed using bacterial and mammalian expression systems has shown an ~186 kDa protein, but no processing of the polyprotein has been observed. Based on these observations, it was proposed that the ORF1 polyprotein does not undergo processing into functional units. We have studied ORF1 polyprotein expression and processing through a baculovirus expression vector system because of the high level expression and post-translational modification abilities of this system. Results The baculovirus expressed ORF1 polyprotein was processed into smaller fragments that could be detected using antibodies directed against tags engineered at both ends. Processing of this ~192 kDa tagged ORF1 polyprotein and accumulation of lower molecular weight species took place in a time-dependent manner. This processing was inhibited by E-64d, a cell-permeable cysteine protease inhibitor. MALDI-TOF analysis of a 35 kDa processed fragment revealed 9 peptide sequences that matched the HEV methyltransferase (MeT), the first putative domain of the ORF1 polyprotein. Antibodies to the MeT region also revealed an ORF1 processing pattern identical to that observed for the N-terminal tag. Conclusion When expressed through baculovirus, the ORF1 polyprotein of HEV was processed into smaller proteins that correlated with their proposed functional domains. Though the involvement of non-cysteine protease(s) could not be be ruled out, this processing mainly depended upon a cysteine protease.
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Chakraborty M, Bart HJ. Separation of Toluene and n-Heptane through Emulsion Liquid Membranes Containing Ag+ as Carrier. Chem Eng Technol 2005. [DOI: 10.1002/ceat.200500239] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chakraborty M, Bart HJ. Studies on Separation Mechanism of Toluene from n-Heptane using Ag+ Containing Emulsion Liquid Membranes. CHEM-ING-TECH 2005. [DOI: 10.1002/cite.200590139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chakraborty M, Narayanan K, Sivaprakash MK. In vivo enhancement of nucleopolyhedrovirus of oriental Armyworm, Mythimna separata using spindles from Helicoverpa armigera entomopoxvirus. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2004; 42:121-3. [PMID: 15274494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
When the third instar larvae of M. separata were exposed to eight varying concentrations of polyhedral occlusion bodies (POB's) of nucleopolyhedrovirus of M. separata (MsNPV) ranging from 2.6 x 10(-1) to 2.6 x 10(8) POB's/ml, the percent mortality and incubation period ranged from 16-100% and 14 to 9 days respectively. On the other hand when the same third instar larvae of M. separata were exposed to only five varying concentration of POB's of MsNPV ranging from 2.6 x 10(2) to 2.6 x 10(6), POB's/ml along with a constant dose of entomopox viral spindles from Helicoverpa armigera, the per cent mortality ranged from 63 to 100% with reduction in incubation period from 7 to 4 days respectively. The enhancement index (log10) of the virus was 2.76 or reduction of more than 500 times in LC50. The ability and the mechanism of the spindles from H. armigera entomopoxvirus to enhance the infectivity of MsNPV has been discussed.
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Chakraborty M, Qiu SG, Vasudevan KM, Rangnekar VM. Par-4 drives trafficking and activation of Fas and Fasl to induce prostate cancer cell apoptosis and tumor regression. Cancer Res 2001; 61:7255-63. [PMID: 11585763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Prostate cancer cells are generally resistant to apoptosis by conventional therapy. During a search for molecules that may overcome prostate cancer cell survival mechanisms, we identified the prostate apoptosis response-4 (Par-4) gene. Par-4 induced apoptosis of selective prostate cancer cells PC-3, DU-145, and TSU-Pr and caused tumor regression by inhibition of NF-kappaB activity and cell membrane trafficking of Fas and FasL that leads to the activation of the Fas-Fas-associated death domain-caspase-8 pro-death pathway. Neither Fas pathway activation alone nor inhibition of NF-kappaB activity with IkappaB-super repressor was sufficient to induce apoptosis of prostate cancer cells. Coregulation of these two pathways was essential and sufficient for Par-4 to induce apoptosis. On the other hand, prostate cancer cells LNCaP or normal prostatic epithelial cells that were resistant to apoptosis by Par-4 did not show Fas or FasL trafficking. These findings identify a mechanism of apoptosis by Par-4 and suggest that Par-4 may have therapeutic potential.
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Rizvi AA, Petry R, Arnold MB, Chakraborty M. Beneficial effects of continuous subcutaneous insulin infusion in older patients with long-standing type 1 diabetes. Endocr Pract 2001; 7:364-9. [PMID: 11585372 DOI: 10.4158/ep.7.5.364] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To assess the effect of continuous subcutaneous insulin infusion (CSII) on glycemic control, hypoglycemia, and daily insulin requirements in five older patients with long-standing type 1 diabetes previously treated with multiple-dose insulin injections (MDII). METHODS We undertook a retrospective analysis of five older patients (three women and two men) with type 1 diabetes and a mean age of 66.4 years (range, 57 to 76). The mean duration of disease was 33 years (range, 18 to 49), and all patients had suboptimal glycemic control (glycosylated hemoglobin or HbA(1c) >8.0%), presence of microvascular complications, and unacceptably frequent hypoglycemia during MDII therapy. A diabetes care team monitored their clinical course after their treatment was changed to a CSII regimen. Data pertaining to HbA(1c), severe hypoglycemia, and insulin dose before and after conversion to CSII were compared with use of paired t tests. RESULTS After initiation of CSII therapy, the mean HbA(1c) value decreased from 9.16% to 7.6% (P<0.0025), the rate of severe hypoglycemia decreased from 3.2 episodes to 0.4 episode per year (P<0.02), and the mean total daily insulin dose was reduced from 44.9 IU to 32.4 IU (P<0.05) during a mean duration of 12.6 months of CSII therapy. CONCLUSION Insulin pump therapy can prove highly beneficial in older patients with type 1 diabetes by improving glycemic control, reducing hypoglycemic episodes and insulin dosage, and possibly increasing treatment satisfaction. These changes can potentially prevent morbidity and prove to be cost-effective. For implementation of pump conversion to be safe and successful, careful patient selection, proper education, and ongoing support through a comprehensive diabetes education and management program are imperative. Future reports of experience with CSII in elderly patients should help to elucidate its promising advantages in this patient population and provide guidelines for use.
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Roy B, Chowdhury A, Kundu S, Santra A, Dey B, Chakraborty M, Majumder PP. Increased risk of antituberculosis drug-induced hepatotoxicity in individuals with glutathione S-transferase M1 'null' mutation. J Gastroenterol Hepatol 2001; 16:1033-7. [PMID: 11595069 DOI: 10.1046/j.1440-1746.2001.02585.x] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Pathogenesis and genetic factors influencing predisposition to antituberculosis drug (ATD)-induced hepatotoxicity are not clear. Polymorphism at the genetic locus of a drug and xenobiotic compound metabolizing enzyme, N-acetyltransferase type 2 (NAT2), is reported to be associated with the excess generation of toxic reactive metabolites. Polymorphisms at the glutathione S-transferase (GST) loci (GSTM1 and GSTT1) are involved in the detoxification of these toxic metabolites in the human body to a lesser extent. We have examined whether polymorphisms at these loci are associated with the risk of ATD-induced hepatotoxicity. METHODS In this case-control study, 33 pulmonary tuberculosis patients with ATD-induced hepatotoxicity and 33 pulmonary tuberculosis patients receiving ATD drugs without any evidence of hepatotoxicity were considered as cases and controls, respectively. Point mutations at NAT2 and homozygous 'null' mutations at GSTM1 and GSTT1 genes were looked into genomic DNA, isolated from peripheral blood mononuclear cells by using polymerase chain reaction (PCR). RESULTS The frequency of homozygous 'null' mutation at the GSTM1 gene was significantly higher among cases (n = 17, 52%) than controls (n = 8, 24%) (P < 0.05, relative risk 2.13, 95% CI: 1.25-3.10). Frequencies of mutations at GSTT1 and NAT2 genes did not differ significantly between cases and controls. CONCLUSION Homozygous 'null' mutation at the GSTM1 gene might predispose an individual to ATD-induced hepatotoxicity.
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Roy B, Majumder PP, Dey B, Chakraborty M, Banerjee S, Roy M, Mukherjee N, Sil SK. Ethnic differences in distributions of GSTM1 and GSTT1 homozygous "null" genotypes in India. Hum Biol 2001; 73:443-50. [PMID: 11459424 DOI: 10.1353/hub.2001.0040] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We estimated the frequencies of GSTM1 and GSTT1 "null" homozygotes in 10 different ethnic populations of India by a genotyping method based on polymerase chain reaction. These populations, inhabiting diverse geographical locations and occupying various positions in the sociocultural hierarchy, were represented by a sample of 299 unrelated individuals. Frequencies of GSTM1 and GSTT1 "null" homozygotes varied from 20% to 79% and 3% to 39%, respectively, across the study populations. Maximum frequencies of GSTM1 and GSTT1 "null" homozygotes (79% and 39%, respectively) have been observed in the same population (Jamatia). Frequencies of homozygous "null" genotypes at the GSTM1 and GSTT1 loci show a significant positive correlation in these populations, which is contrary to expectations. A possible implication is that the two enzymes are working in tandem, instead of working in a complementary way.
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Chakraborty M, Chatterjee D. Coupling of nerve growth factor to its receptor: inhibition by anti-GM3 ganglioside antibody. Cell Mol Neurobiol 2001; 21:101-7. [PMID: 11440194 DOI: 10.1023/a:1007129514216] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
1. Normal differentiation of PC 12 cells and dorsal root ganglionic neurons in culture need nerve growth factor (NGF) for their neurite outgrowth. 2. An antibody against GM3 ganglioside was found to inhibit the nerve growth factor mediated neurite formation of both the cells in vitro significantly. 3. Further analysis revealed that the binding of 125I-NGF to live PC 12 cells could be markedly inhibited by anti-GM3 antibody in a dose dependent manner. 4. Scatchard analysis revealed that in the presence of anti-GM3 antibody only some low affinity binding sites were available for NGF-high affinity binding sites were totally blocked. 5. These results further strengthen the hypothesis that anti-GM3 antibody affects neuronal cell growth by interfering with the coupling of growth factors to their cell surface receptors.
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Foon KA, John WJ, Chakraborty M, Das R, Teitelbaum A, Garrison J, Kashala O, Chatterjee SK, Bhattacharya-Chatterjee M. Clinical and immune responses in resected colon cancer patients treated with anti-idiotype monoclonal antibody vaccine that mimics the carcinoembryonic antigen. J Clin Oncol 1999; 17:2889-5. [PMID: 10561367 DOI: 10.1200/jco.1999.17.9.2889] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE We generated an anti-idiotype antibody, designated CeaVac, that is an internal image of the carcinoembryonic antigen (CEA). We previously demonstrated that the majority of patients with advanced colorectal cancer generate specific anti-CEA responses. The purpose of the current study was to treat patients with surgically resected colon cancer with CeaVac to determine the immune response and clinical outcome to treatment with vaccine. We also compared the immune responses between patients treated with fluorouracil (5-FU) chemotherapy regimens plus vaccine versus vaccine alone. PATIENTS AND METHODS Thirty-two patients with resected Dukes' B, C, and D, and incompletely resected Dukes' D disease were treated with 2 mg of CeaVac every other week for four injections and then monthly until tumor recurrence or progression. Fourteen patients were treated concurrently with 5-FU chemotherapy regimens. RESULTS All 32 patients entered onto this trial generated high-titer immunoglobulin G and T-cell proliferative immune responses against CEA. The 5-FU regimens did not have a qualitative or quantitative effect on the immune response. Three of 15 patients with Dukes' B and C disease progressed at 19, 24, and 35 months. Seven of eight patients with completely resected Dukes' D disease remained on study from 12 to 33 months; one patient with resected Dukes' D disease relapsed at 9 months. One patient with incompletely resected Dukes' D disease remained on study at 14 months without evidence of progression; eight experienced disease progression at 6 to 31 months. CONCLUSION CeaVac consistently generated a potent anti-CEA humoral and cellular immune response in all 32 patients entered onto this trial. A number of very high-risk patients continue on study. 5-FU regimens, which are the standard of care for patients with Dukes' C disease, did not affect the immune response. These data warrant a phase III trial for patients with resected colon cancer.
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Foon K, Lutzky J, Hutchins L, Teitelbaum A, Kashala O, Chakraborty M, Reisfeld R, Chatterjee M. Clinical and immune responses in metastatic melanoma patients immunized with an anti-idiotype (anti-Id) monoclonal antibody (mAb) mimicking disialoganglioside gd21. Eur J Cancer 1999. [DOI: 10.1016/s0959-8049(99)81849-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Mukherjee N, Majumder PP, Roy B, Roy M, Dey B, Chakraborty M, Banerjee S. Variation at 4 short tandem repeat loci in 8 population groups of India. Hum Biol 1999; 71:439-46. [PMID: 10380378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
We have determined the nature and extent of variation at 4 STR loci (CSF1P0, TPOX, TH01, VWA) in 8 caste and tribal population groups of eastern and northern India. Large differences in allele frequencies among the groups were found. Average heterozygosities in all populations were high (approximately 80%). The overall extent of gene differentiation among the 8 groups was high (GST = 0.04). The nature of genomic affinities based on these 4 STR loci does not completely agree with our earlier finding based on classical genetic markers that geographic proximity of habitat has a greater influence on genetic similarity between populations than sociocultural proximity does.
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Majumder PP, Roy B, Banerjee S, Chakraborty M, Dey B, Mukherjee N, Roy M, Thakurta PG, Sil SK. Human-specific insertion/deletion polymorphisms in Indian populations and their possible evolutionary implications. Eur J Hum Genet 1999; 7:435-46. [PMID: 10352934 DOI: 10.1038/sj.ejhg.5200317] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
DNA samples from 396 unrelated individuals belonging to 14 ethnic populations of India, inhabiting various geographical locations and occupying various positions in the socio-cultural hierarchy, were analysed in respect of 8 human-specific polymorphic insertion/deletion loci. All loci, except Alu CD4, were found to be highly polymorphic in all populations. The levels of average heterozygosities were found to be very high in all populations and, in most populations, also higher than those predicted by the island model of population structure. The coefficient of gene differentiation among Indian populations was found to be higher than populations in most other global regions, except Africa. These results are discussed in the light of two possible scenarios of evolution of Indian populations in the broader context of human evolution.
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Foon KA, Sen G, Hutchins L, Kashala OL, Baral R, Banerjee M, Chakraborty M, Garrison J, Reisfeld RA, Bhattacharya-Chatterjee M. Antibody responses in melanoma patients immunized with an anti-idiotype antibody mimicking disialoganglioside GD2. Clin Cancer Res 1998; 4:1117-24. [PMID: 9607568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We initiated a clinical trial for patients with advanced malignant melanoma treated with an anti-idiotype antibody that mimics the disialoganglioside GD2. We report the clinical and immune responses of the first 12 patients entered into this trial. Patients received 1-, 2-, 4-, or 8-mg doses of the anti-idiotype antibody mixed with 100 microg of QS-21 adjuvant every other week, four times, and then monthly. Twelve patients have been on trial for 2-23 months, and all of them have generated immune responses. Patients were removed from the study if they demonstrated disease progression. Hyperimmune sera from all 12 patients revealed an anti-anti-idiotypic Ab3 response, as demonstrated by the inhibition of Ab2 binding to Ab1 by patients' immune sera. To further test the anti-anti-idiotypic response, patients' Ab3 antibodies were affinity purified on Sepharose 4B columns containing adsorbed immunizing anti-idiotype immunoglobulin. Purified Ab3 of all patients studied inhibited binding of Ab1 to a GD2-positive cell line. Purified Ab3 also inhibited binding of Ab1 to purified GD2, in a manner comparable to equal quantities of purified Ab1. The patient Ab3 was truly an Ab1' because it specifically bound to purified disialoganglioside GD2. The isotypic specificity of the Ab3 antibody was predominantly IgG, with only minimal IgM. The predominant IgG subclass was IgG1, with approximately equal quantities of IgG2, IgG3, and IgG4. These Ab3 antibodies reacted specifically with tumor cells expressing GD2 by immune flow cytometry and immunoperoxidase assays. Five patients' Ab3 antibodies studied for antibody-dependent cellular cytotoxicity were positive. One patient had a complete clinical response, with resolution of soft tissue disease, and six patients had stable disease, ranging from 9 to 23 months, and are being continued on vaccine therapy. Toxicity consisted of local reaction at the site of the injection, including induration and pain that generally resolved within a few days. Mild fever and chills were observed in 75% of the patients but rarely required acetaminophen. There was no additional toxicity, including abdominal pain that was previously seen with infusion of murine monoclonal anti-GD2 antibody. Current trials include patients with stage III melanoma and small cell lung cancer. Future trials will attempt to enhance the antitumor response by the addition of interleukin 2, granulocyte macrophage colony-stimulating factor, and other cytokines, together with the 1A7 vaccine.
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Chatterjee SK, Tripathi PK, Chakraborty M, Yannelli J, Wang H, Foon KA, Maier CC, Blalock JE, Bhattacharya-Chatterjee M. Molecular mimicry of carcinoembryonic antigen by peptides derived from the structure of an anti-idiotype antibody. Cancer Res 1998; 58:1217-24. [PMID: 9515808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Our goal was to use carcinoembryonic antigen (CEA) as a target for immunotherapy in CEA-positive cancer patients who are all immune tolerant to the native antigen. We isolated and characterized an anti-idiotype monoclonal antibody 3H1, which mimics a distinct and specific epitope of the Mr 180,000 CEA and can be used as a surrogate for CEA. In Phase Ib clinical trials in a group of 23 advanced colorectal cancer patients, 3H1 induced both humoral and cellular anti-3H1 responses, as well as anti-CEA immunity. To study the cellular immunity invoked by 3H1 at the molecular level, we have cloned and sequenced the cDNAs encoding the variable heavy and light chains of 3H1 and deduced the amino acid sequences of the encoded proteins. To identify any cross-reactive peptides of 3H1 and CEA, we compared the amino acid sequences of 3H1 with those of CEA and found several regions of homology in 3H1 heavy and light chain variable domains, as well as in the framework regions. To search for potential cross-reactive T-cell epitopes, a number of peptides were synthesized based on 3H1/CEA homology and were used as stimulants in cell proliferation assays, using peripheral blood mononuclear cells from a group of 3H1-immunized CEA-positive cancer patients in the adjuvant setting. Two partially homologous peptides, designated LCD-2 (from 3H1) and CEA-B (from CEA), were identified in 10 of 21 adjuvant patients by strong proliferation responses (stimulation index, 3-50-fold), which were extensively studied in five of these individuals over an extended period of time (12-24 months). We saw no correlation with the MHC class I haplotype of the patients. Analysis of the subtype of the responding T cells demonstrated that primarily CD4+ T cells were stimulated by both 3H1 and 3H1-derived peptides. Interleukin 2, interleukin 4, and IFN-gamma were assayed in the culture medium of peripheral blood mononuclear cells stimulated with 3H1, CEA, and LCD-2 to determine the T-cell helper subset induced by these stimulants. The in vitro responses were mainly associated with secretion of IFN-gamma, which suggested that the induced T cells were most likely CD4+ Th1 type. Future studies will include the design of second-generation LCD-2 and CEA peptides to further enhance antigenicity, to characterize the responding T-cell populations more fully, and to test refined peptides for immunogenicity.
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Roy B, Dey B, Chakraborty M, Majumder PP. Frequency of homozygous null mutation at the glutathione-s-transferase M1 locus in some populations of Orissa, India. ANTHROPOLOGISCHER ANZEIGER; BERICHT UBER DIE BIOLOGISCH-ANTHROPOLOGISCHE LITERATUR 1998; 56:43-7. [PMID: 9569978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
GSTM1, one of the mu type glutathione-s-transferase isozymes in human, has been observed to be inherited dominantly, and the polymorphism of this gene can be detected by polymerase chain reaction (PCR). In this report we have determined the frequency of a homozygous deletion mutation of the GSTM1 gene in some populations of the Sundergarh District in Orissa, India. About 24% of unrelated individuals (n = 72) were detected to carry this deletion mutation in homozygous form. Possible implications of this homozygous deletion are discussed.
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Sen G, Chakraborty M, Foon KA, Reisfeld RA, Bhattacharya-Chatterjee MB. Induction of IgG antibodies by an anti-idiotype antibody mimicking disialoganglioside GD2. J Immunother 1998; 21:75-83. [PMID: 9456440 DOI: 10.1097/00002371-199801000-00010] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The anti-idiotype (Id) monoclonal antibody (mAb) 1A7 immunoglobulin G1 (IgG1, kappa), raised in syngeneic mice against the murine anti-ganglioside GD2 mAb 14G2a mimics a carbohydrate epitope on GD2 and serves as a surrogate protein antigen for this disialoganglioside. Immunization of allogeneic C57BL/6 mice and rabbits with 1A7 induced anti-GD2 antibodies of IgG isotype that recognize purified GD2 by enzyme-linked immunosorbent assay (ELISA) and GD2-positive human melanoma cells (M21/P6) by fluorescence-activated cell sorter (FACS) analysis. The specificity of the antisera for GD2 was further confirmed by dot-blot analysis. These antisera also specifically lyse GD2-positive M21/P6 target cells in an antibody-dependent cellular cytotoxicity assay. Taken together, these results suggest that the anti-Id 1A7 can induce GD2-specific IgG antibodies that can recognize cell surface-associated as well as soluble disialoganglioside GD2.
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Dar L, Sharma SK, Bhanu NV, Broor S, Chakraborty M, Pande JN, Seth P. Diagnosis of pulmonary tuberculosis by polymerase chain reaction for MPB64 gene: an evaluation in a blind study. THE INDIAN JOURNAL OF CHEST DISEASES & ALLIED SCIENCES 1998; 40:5-16. [PMID: 9727278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Polymerase chain reaction (PCR) has been found to be a sensitive and rapid method to confirm a clinical diagnosis of tuberculosis. We evaluated PCR for M. tuberculosis complex specific MPB64 gene for the diagnosis of pulmonary tuberculosis, in a double blind study. One hundred and eighty-two clinical samples (sputum, bronchioalveolar lavage and pleural fluid) from patients with a clinical diagnosis of pulmonary tuberculosis and 72 samples from patients with non-tubercular pulmonary lesions and normal healthy individuals were included. The samples were coded and clinical details were concealed from the laboratory, where conventional diagnostic methods and PCR were carried out independent of each other. On decoding and analysing the data, PCR was positive in 59% of single sputum samples from clinically diagnosed pulmonary tuberculosis, while M. tuberculosis could be grown in 18% of the samples. PCR could identify M. tuberculosis in 81.8% of the culture positive sputum samples. PCR was also positive in 71.4% of bronchioalveolar lavage (BAL) fluid and 60.7% pleural fluid samples from clinically suspected cases, which were mostly culture negative. On comparison with response to treatment, PCR was positive in 79.5% of patients who improved on anti-tuberculosis treatment, with a positive predictive value of 92%. PCR for MPB64 gene provides a useful alternative for the diagnosis of pulmonary tuberculosis from sputum and paucibacillary samples like BAL and pleural fluid in which conventional methods show low sensitivity, especially in areas from which strains show a low copy number of other PCR targets like the IS 6110 insertion sequence.
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Chakraborty P, Bhattacharya S, Chakraborty M, Pal B. Serodiagnosis and immune profile in rheumatoid arthritis. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1997; 95:586-8. [PMID: 9567589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
One hundred and seventy-five cases of clinically diagnosed rheumatoid arthritis, 82 non-rheumatoid cases suffering from various other diseases and 40 healthy normal controls were investigated for detection of rheumatoid factor, quantitation of serum immunoglobulin, demonstration of antinuclear antibody (ANA) and LE cell phenomenon. Microlatex agglutination test of serum for rheumatoid factor (RF) showed 64% positivity in rheumatoid group and 1.2% positivity in non-rheumatoid group. All three immunoglobulins (IgG, IgM, IgA) were found to be raised in serum of patients with rheumatoid arthritis, whereas only IgA level was elevated in serum of patients with non-rheumatoid diseases. ANA and LE cell phenomenon were observed in 3.4% and 2.8% cases respectively in cases of clinically diagnosed rheumatoid arthritis who had been suffering from severe active rheumatoid arthritis. In non-rheumatoid group RF was positive in significant titre in only one case of leprosy. Synovial fluid and synovium were found to be heavily infiltrated by plasma cells and lymphocytes. RF appears first in synovial fluid and then in serum. Hence RF titre in blood may not attain significant level for the first several months.
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Sen G, Chakraborty M, Foon KA, Reisfeld RA, Bhattacharya-Chatterjee M. Preclinical evaluation in nonhuman primates of murine monoclonal anti-idiotype antibody that mimics the disialoganglioside GD2. Clin Cancer Res 1997; 3:1969-76. [PMID: 9815586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The antiganglioside GD2 monoclonal antibody 14G2a (Ab1) served as an immunogen to generate the anti-idiotype (anti-Id) 1A7 (IgG1,kappa), which mimics GD2 both antigenically and biologically. Anti-Id 1A7 induced anti-GD2 antibodies in mice and rabbits. In this preclinical study, a pair of cynomolgus monkeys, immunized with 1A7 that had been mixed with QS-21 adjuvant, produced anti-anti-Id antibodies (Ab3), which reacted with the GD2-positive melanoma cell line M21/P6 cells but not with GD2-negative LS174-T cells. The Ab3 shared Ids with mAb 14G2a (Ab1), as demonstrated by their ability to inhibit binding of 1A7 to this Ab1. The Ab3 bound specifically to purified GD2 antigen and competed with the Ab1 14G2a in binding to a GD2-positive melanoma cell line or to purified GD2, suggesting that Ab1 and Ab3 may bind to the same epitope and may behave as an Ab1-like antibody (Ab1'). The isotype of the GD2-specific antibodies was mostly IgG in nature. The specificity of the antibodies for GD2 was further confirmed by dot blot analysis. These antisera also specifically lysed GD2-positive target cells in an antibody-dependent cellular cytotoxicity assay. The induction of anti-GD2 responses in monkeys did not cause any apparent side effects, despite the fact that GD2 antigen is expressed by many normal tissues of these animals. Taken together, these results suggest that anti-Id 1A7 can induce GD2-specific antibodies in nonhuman primates and can thus serve as a potential network antigen for triggering active anti-GD2 antibodies in patients with GD2-positive neuroectodermal tumors.
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Billecocq A, Horne WC, Chakraborty M, Takeyasu K, Levenson R, Baron R. 1,25-Dihydroxyvitamin D3 selectively induces increased expression of the Na,K-ATPase beta 1 subunit in avian myelomonocytic cells without a concomitant change in Na,K-ATPase activity. J Cell Physiol 1997; 172:221-9. [PMID: 9258343 DOI: 10.1002/(sici)1097-4652(199708)172:2<221::aid-jcp9>3.0.co;2-q] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Treatment of avian myelomonocytic cells with 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) results in an approximately two fold increase in levels of Na,K-ATPase beta 1 subunit mRNA and protein (both total and plasma membrane-associated). The changes in beta 1 subunit expression occur in the absence of a detectable increase in expression of any of the three alpha subunit isoforms or in Na,K-ATPase activity. The selective induction of the expression of the beta subunit in avian myelomonocytic cells by 1,25(OH)2D3 reveals a previously unobserved feature of the regulation of Na,K-ATPase expression, while the targeting of beta subunit polypeptides to the plasma membrane in the absence of a corresponding increase in active Na,K-ATPase suggests that, in these cells, transport of the beta subunit to the plasma membrane may be independent of its binding to the alpha subunit.
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Foon KA, John WJ, Chakraborty M, Sherratt A, Garrison J, Flett M, Bhattacharya-Chatterjee M. Clinical and immune responses in advanced colorectal cancer patients treated with anti-idiotype monoclonal antibody vaccine that mimics the carcinoembryonic antigen. Clin Cancer Res 1997; 3:1267-76. [PMID: 9815809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Carcinoembryonic antigen (CEA) is expressed in a wide variety of adenocarcinomas, and it is well recognized that cancer patients are immunologically "tolerant" to CEA. The purpose of this study was to determine whether we could break immune tolerance to CEA by vaccinating patients with a monoclonal anti-idiotype antibody that is the internal image of CEA and to determine what impact this might have on patient survival. Twenty-four patients with advanced CEA-positive colorectal cancer who failed standard therapies except for two were entered into this Phase Ib trial. One patient was considered not assessable, because on the day of entering into the study, she was diagnosed with acute myelogenous leukemia. Patients were treated with 1, 2, or 4 mg of aluminum hydroxide-precipitated 3H1 anti-idiotype antibody every other week for four injections and then monthly until tumor progression was observed. Immunological monitoring included humoral and cellular idiotypic and CEA responses, and all patients were evaluated for toxicity, response, and survival. Hyperimmune sera from 17 of 23 patients demonstrated an anti-anti-idiotypic Ab3 response, and 13 of these responses were demonstrated to be true anti-CEA responses (Ab1'). The antibody response was polyclonal, and 11 mediated antibody-dependent cellular cytotoxicity. Ten patients had idiotypic T-cell responses, and five had specific T-cell responses to CEA. None of the patients had objective clinical responses, but overall median survival for the 23 evaluable patients was 11.3 months, with 44% 1-year survival (95% confidence interval, 23-64%). Toxicity was limited to local swelling and minimal pain. Anti-idiotype monoclonal antibody 3H1 that mimics CEA was able to break immune tolerance in the majority of treated patients. Overall survival of 11.3 months was comparable to other phase II data with advanced colorectal cancer patients treated with a variety of chemotherapy agents, including irinotecan, with considerably less toxicity. Although it is not clear that the vaccine itself had an impact on survival, this should be determined in a Phase III randomized trial.
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Chakraborty M, Saha JB, Bhattacharya RN, Roy A, Ram R. Epidemiological correlates of dental caries in an urban slum of West Bengal. Indian J Public Health 1997; 41:56-60, 67. [PMID: 9988979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
The overall prevalence of dental caries was found to be 57.47 percent in an urban slum irrespective of sex, with a maximum of 75.88 percent in the age group of 5-9 years. Habit of taking hard and sticky food, bad oral hygiene were some of the important epidemiological correlates. Fluoride content of drinking water did not show any significant role.
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Pervin S, Chakraborty M, Bhattacharya-Chatterjee M, Zeytin H, Foon KA, Chatterjee SK. Induction of antitumor immunity by an anti-idiotype antibody mimicking carcinoembryonic antigen. Cancer Res 1997; 57:728-34. [PMID: 9044852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Carcinoembryonic antigen (CEA) is a tumor-associated antigen expressed on most gastrointestinal adenocarcinomas and is a putative target for cancer immunotherapy. We developed a murine monoclonal anti-idiotype (anti-Id) antibody, 3H1, which mimics a specific epitope of CEA, for cancer immunotherapy. In this study, the efficacy of 3H1 as a tumor vaccine was evaluated in a murine tumor model. In this model, the murine colorectal cancer cell line MC-38 was transduced with the human CEA gene and injected into syngeneic C57BL/6 (H-2b) mice. Immunization of naive mice with 3H1 conjugated with keyhole limpet hemocyanin Freund's adjuvant induced humoral and cellular anti-3H1 as well as anti-CEA immunity. Mice immunized with 3H1 were protected against a challenge with lethal doses of MC-38-cea, whereas no protection was observed when 3H1 vaccinated mice were challenged with CEA negative MC-38 cells or when mice were vaccinated with an unrelated anti-Id antibody and challenged with MC-38-cea cells (P < 0.003). These data demonstrate that the 3H1 vaccine can induce protective CEA-specific antitumor immunity.
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Seth P, Ahuja GK, Bhanu NV, Behari M, Bhowmik S, Broor S, Dar L, Chakraborty M. Evaluation of polymerase chain reaction for rapid diagnosis of clinically suspected tuberculous meningitis. TUBERCLE AND LUNG DISEASE : THE OFFICIAL JOURNAL OF THE INTERNATIONAL UNION AGAINST TUBERCULOSIS AND LUNG DISEASE 1996; 77:353-7. [PMID: 8796252 DOI: 10.1016/s0962-8479(96)90101-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
SETTING Since conventional bacteriological methods rarely detect Mycobacterium tuberculosis in cerebrospinal fluid (CSF) and are of limited use in the diagnosis of tuberculous meningitis (TBM), clinical features suggestive of TBM supported by indirect evidence such as CSF examination and computerized tomography (CT) of the head have been used for the early diagnosis of TBM. OBJECTIVE We evaluated the efficacy of polymerase chain reaction (PCR) in the diagnosis of TBM. METHODS Coded CSF samples from 40 patients with TBM and from 49 patients with other neurological disorders were processed. In the absence of a reliable sensitive and specific test for M. tuberculosis in CSF, we used a set of established clinical criteria as the gold standard. Accordingly, the patients were divided into definite, highly probable, probable and possible TBM. The samples were decoded only after completion of the laboratory tests. RESULTS PCR was positive in 2/4, 19/20, 13/16 patients with highly probable, probable and possible TBM respectively. None of the samples were positive by conventional bacteriological methods. However, 3/49 CSF samples from non-TBM patients were also found positive by PCR. PCR detected M. tuberculosis genomic DNA in the CSF of 85% of clinically suspected TBM cases and 6.1% of non-tuberculous controls. CONCLUSION PCR, along with the suggested clinical criteria, offers a rapid and fairly accurate diagnosis of TBM.
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Chakraborty M, Foon KA, Kohler H, Bhattacharya-Chatterjee M. Preclinical evaluation in nonhuman primates of an anti-idiotypic antibody that mimicks the carcinoembryonic antigen. JOURNAL OF IMMUNOTHERAPY WITH EMPHASIS ON TUMOR IMMUNOLOGY : OFFICIAL JOURNAL OF THE SOCIETY FOR BIOLOGICAL THERAPY 1995; 18:95-103. [PMID: 8574471 DOI: 10.1097/00002371-199508000-00003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have developed and characterized a murine monoclonal antiidiotype (Id) antibody (Ab2), designated 3H1 (IgG1-k) that mimics human carcinoembryonic antigen (CEA). 3H1 was raised against an anti-CEA monoclonal antibody (mAb) 8019 (Ab1) that recognizes a distinct and specific epitope of the 180,000 MW CEA. 3H1 induced specific anti-CEA immune responses in mice and rabbits. In this preclinical study, cynomolgus monkeys (Macaca fascicularis) were immunized with aluminum hydroxide-precipitated 3H1 and tested for the induction of anti-CEA antibodies. Monkeys were injected with 2 mg of 3H1, intracutaneously, four times biweekly. All monkeys developed specific anti-anti-Id (Ab3) responses that were capable of inhibiting binding of the immunizing 3H1 (Ab2) to 8019 (Ab1) and vice versa. Furthermore, immune sera from monkeys contained Ab3 (Abl') antibody that bound to CEA-positive colon carcinoma cell lines but not to CEA-negative MOLT-4 or melanoma cell lines. Also, the Ab3 reacted with purified CEA and competed with Ab1 (8019) for binding to CEA positive LS174-T cells, suggesting that Ab1 and Ab3 may bind to the same epitope. In addition, affinity-purified Ab3 from monkey sera immunoprecipitated the same 180,000 MW CEA as Ab1 8019 and showed an identical pattern as the Ab1 on colon carcinoma specimens by immunoperoxidase staining. The induction of anti-tumor antibodies in monkeys did not cause any apparent side effects. These data suggest that internal image anti-Id can induce tumor-specific humoral immune responses in nonhuman primates and can serve as potential network antigen for triggering active anti-CEA antibodies in colorectal cancer patients.
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Foon KA, Chakraborty M, John WJ, Sherratt A, Köhler H, Bhattacharya-Chatterjee M. Immune response to the carcinoembryonic antigen in patients treated with an anti-idiotype antibody vaccine. J Clin Invest 1995; 96:334-42. [PMID: 7615803 PMCID: PMC185205 DOI: 10.1172/jci118039] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have generated an IgG1 murine monoclonal anti-idiotype antibody (Ab2) designated 3H1, which mimics a specific epitope on the carcinoembryonic antigen (CEA). Patients with CEA positive tumors are immunologically "tolerant" to CEA. We used 3H1 as a surrogate for CEA for vaccine therapy of 12 patients with advanced colorectal cancer. Each of the patients received a minimum of four intracutaneous injections of aluminum hydroxide precipitated 3H1 at either 1, 2, or 4 mg dosage per injection. 9 of 12 patients demonstrated anti-anti-idiotypic (Ab3) response to 3H1. All nine patients generated specific anti-CEA antibody demonstrated by reactivity with radiolabeled purified CEA; some cases were confirmed by immunoprecipitation of purified CEA. We also demonstrated Ab3 stained both autologous and allogeneic colonic tumors. 7 of 12 patients demonstrated idiotype specific T cell proliferative responses and four also showed T cell proliferation to CEA. Toxicity was limited to local reaction with mild fever and chills. All 12 patients eventually progressed after finishing 4-13 dosages. This is the first report demonstrating that a vaccine therapy is capable of breaking "immune tolerance" to CEA in patients with CEA positive tumors. Future studies will focus on treating patients with minimal residual disease.
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Chakraborty M, Mukerjee S, Foon KA, Köhler H, Ceriani RL, Bhattacharya-Chatterjee M. Induction of human breast cancer-specific antibody responses in cynomolgus monkeys by a murine monoclonal anti-idiotype antibody. Cancer Res 1995; 55:1525-30. [PMID: 7533665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We have generated and characterized a murine monoclonal anti-idiotype (Id) antibody, designated 11D10, which biologically and antigenically mimics a distinct and specific epitope of the high molecular weight human milk fat globule primarily expressed by human breast and some other tumor cells at high density. This epitope is identified by mAb BrE1, which was used as the immunizing antibody or Ab1 to generate the anti-Id (Ab2) 11D10. 11D10 induced antitumor immune responses across species barriers, i.e., in mice and rabbits. In preclinical studies, cynomolgus monkeys were immunized with 2 mg of either 11D10 or the isotype- and allotype-matched control Ab2 3H1 after precipitation with aluminum hydroxide. All monkeys developed high titers of antibodies against the immunizing mouse immunoglobulin. Immunization with 11D10 induced anti-anti-idiotype antibodies (Ab3) which reacted with breast cancer cell lines but not with control T-cell and melanoma cell lines. The Ab3 shared idiotypes with BrE1 (Ab1), as demonstrated by their ability to inhibit 11D10 binding to BrE1. The Ab3 obtained with 11D10 bound specifically to human milk fat globule antigen and competed with BrE1 for binding to breast cancer cell lines, suggesting that Ab1 and Ab3 may bind to the same epitope. In addition, Id-specific cellular immune responses were demonstrated in monkeys immunized with 11D10 by T-cell proliferation assays. These results indicate that aluminum hydroxide-precipitated anti-Id 11D10 can induce breast cancer-specific antibodies in nonhuman primates and can serve as a potential network antigen for breast cancer patients.
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Horne WC, Shyu JF, Chakraborty M, Baron R. Signal transduction by calcitonin Multiple ligands, receptors, and signaling pathways. Trends Endocrinol Metab 1994; 5:395-401. [PMID: 18407235 DOI: 10.1016/1043-2760(95)92521-j] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Calcitonin (CT) is a peptide hormone that is secreted by the parafollicular cells of the thyroid in response to elevated serum calcium levels. It acts to reduce serum calcium by inhibiting bone resorption and promoting renal calcium excretion. In addition to this hypocalcemie effect, calcitonin modulates the renal transport of water and several ions other than calcium and acts on the central nervous system to induce analgesia, anorexia, and gastric secretion. The CT receptor, a member of a newly described family of serpentine G protein-coupled receptors, has recently been shown to couple to multiple trimeric G proteins, thereby activating several signaling proteins, including protein kinase C, cAMP-dependent protein kinase and calcium/calmodulin-dependent protein kinase. In kidney proximal tubule cells (LLC-PK1), the CT-activated signaling mechanisms vary in a cell cycle-dependent manner, with the receptor coupling through a G(s) protein during G(2) phase and through a G(i) protein and possibly a G(q) protein during S phase. These signaling mechanisms differentially modulate the activities of Na(+)/K(+)-ATPase and the apical Na(+)/H(+) exchanger, effector molecules that play important roles in transepithelial Na(+) transport. Cloning of CT receptors has revealed the presence of alternatively spliced cassettes, resulting in the expression of different isoforms of the receptor. The availability of these recombinant CT receptors has allowed preliminary characterization of the effects of changes in the receptor's structure on its ligand binding and signal transduction properties. Thus, the cellular and molecular biology of CT is complex, with several structurally related peptide ligands and multiple isoforms of the CT receptor that can independently activate diverse signaling pathways. As the recent exciting results in this field are extended, we can expect rapid progress in understanding the molecular basis of the diverse effects of CT and, possibly, of the CT-related peptides CGRP and amylin.
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Chakraborty M, Chatterjee D, Gorelick FS, Baron R. Cell cycle-dependent and kinase-specific regulation of the apical Na/H exchanger and the Na,K-ATPase in the kidney cell line LLC-PK1 by calcitonin. Proc Natl Acad Sci U S A 1994; 91:2115-9. [PMID: 8134357 PMCID: PMC43320 DOI: 10.1073/pnas.91.6.2115] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Calcitonin (CT), which regulates serum calcium through its actions in bone and the kidney tubule, also has a potent natriuretic effect in vivo. Na reabsorption in the proximal kidney tubule is mostly dependent on the activity of the Na,K-ATPase and the apical Na/H exchanger. We have previously shown that CT regulates the activity of the Na,K-ATPase in the proximal kidney tubule cell line LLC-PK1 in a cell cycle-dependent manner. We report here that, in the same cells, CT also regulates the Na/H exchanger through a cell cycle-specific activation of the Ca/calmodulin-dependent protein kinase II. In G2 phase, no changes in ethylisopropyl amiloride-sensitive 22Na uptake is observed, despite an increase in cAMP. In contrast, the hormone inhibits the apical exchanger when the cells are in S phase, resulting in an 80% inhibition of 22Na uptake. These results demonstrate that CT affects the activity of the two major proximal tubule Na transport systems and may help clarify the mechanisms by which CT regulates Na+ reabsorption.
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Chandra N, Chakraborty M. Auger electron spectroscopy of molecules: Theory for angular and spin correlations with photoelectrons. J Chem Phys 1993. [DOI: 10.1063/1.465713] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Chakraborty M, Anderson GM, Chakraborty A, Chatterjee D. Accumulation of high level of pp60c-srcN is an early event during GM3-antibody mediated differentiation of neuro-2a neuroblastoma cells. Brain Res 1993; 625:197-202. [PMID: 7506109 DOI: 10.1016/0006-8993(93)91059-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Neuro-2a neuroblastoma cells, when differentiated via a cAMP-dependent pathway by treatment with anti-GM3 monoclonal antibody, accumulated a high level of pp60c-src protein and pp60c-src kinase activity just before the onset of neurite formation. The specific kinase activity of the accumulated c-src protein was found to be comparable to that of normal cerebellar neurons, but was about 6- to 8-fold higher than that of normal astrocytes. These results, and migrations of peptide fragments in the SDS-polyacrylamide gels after V8 proteolysis, strongly indicate the accumulation of the neuron-specific isoform of the c-src protein (pp60c-srcN) in the GM3 antibody-treated Neuro-2a cells. Similar high levels of pp60c-src protein and pp60c-src kinase activity were observed in the Neuro-2a cells differentiated via a cAMP-dependent pathway by treatment with dibutyryl cAMP, but not in the same cell line when differentiated via a cAMP-independent pathway with 5-bromo-2'-deoxyuridine. These results demonstrate that the accumulation of high levels of the neuron-specific isoform of the pp60c-src protein (pp60c-srcN) in the Neuro-2a neuroblastoma cells depends on the specific signal transduction pathway involved during the differentiation of these cells.
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Chakraborty M, Mandal C. Immuno-suppressive effect of human alphafetoprotein: a cross species study. Immunol Invest 1993; 22:329-39. [PMID: 7691735 DOI: 10.3109/08820139309063412] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Alphafetoprotein (AFP) is the major serum protein of fetal life in human and other mammalian species. The phylogenetical conservatism of AFP demonstrated by extensive immunological cross reaction between human AFP and AFP of a number of species, suggest that AFP plays a general role in the successful pregnancy of all mammalian species. The present work clearly demonstrates the antiproliferative effect of human AFP on lymphocytes, harvested from normal human donors. The inhibitory effect of human AFP is quite significant in the same dose during blastic transformations of the lymphocytes. In this study, peripheral blood mononuclear cells were induced to blastic transformations with phytohaemagglutinin (PHA-M) and the effect of AFP was quantified by the incorporation of [3H]-thymidine into newly synthesized DNA during 24 hrs pulse. Moreover, human AFP shows similar immuno-suppressive effect to other species of lymphocytes also. In all the three species (mouse, rat and hamster) studied, a parallelism was noted in their respective percentage of thymidine incorporation values at the comparable doses. These results establish a cross species inhibitory effect of human AFP and it may be stated that this effect is directly targeted on T-helper cells and has no interaction with interleukin-2 (IL-2).
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92
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Chatterjee D, Neff L, Chakraborty M, Fabricant C, Baron R. Sensitivity to nitrate and other oxyanions further distinguishes the vanadate-sensitive osteoclast proton pump from other vacuolar H(+)-ATPases. Biochemistry 1993; 32:2808-12. [PMID: 8457547 DOI: 10.1021/bi00062a011] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The osteoclast proton pump (OC H(+)-ATPase) differs from other vacuolar H(+)-ATPases (V-ATPases) in its sensitivity to vanadate and in the subunit composition of its catalytic domain, where isoforms of subunits A and B are expressed [Chatterjee et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 6257-6261]. In the present study, the sensitivity of the osteoclast H(+)-ATPase to various oxyanions was tested. The results indicate that H+ transport by microsomal preparations isolated from chicken osteoclasts is 20-100-fold more sensitive to nitrate that any other animal and fungal V-ATPases and 10-20-fold more sensitive than plant V-ATPases, as is the ATPase activity of the affinity-purified enzyme. This inhibition by nitrate is not due to a chaotropic effect of the oxyanion and is complete at 1 mM concentrations with an IC50 of 100 microM. In contrast, proton transport by the OC H(+)-ATPase was insensitive to other oxyanions (phosphate, sulfate, and acetate) which inhibit other V-ATPases. These results further demonstrate that the proton pump present in osteoclast membranes differs from other vacuolar ATPases. It is speculated that, since cells of the macrophage lineage can generate high intracellular concentrations of nitrate, it may be possible to physiologically or therapeutically regulate the activity of the OC H(+)-ATPase in the osteoclast without affecting the other V-ATPases in the same or in other cells.
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93
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Chakraborty M, Lahiri P, Chatterjee D. Thyroidal influence on the cell surface GM1 of granule cells: its significance in cell migration during rat brain development. Cell Mol Neurobiol 1992; 12:589-96. [PMID: 1490275 DOI: 10.1007/bf00711238] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. No difference was observed in the in vitro growing ability of granule cells isolated from hypothyroid or normal rat brain. When granule cells were taken from hypothyroid rat brain and grown in normal culture medium containing 10% fetal calf serum, they behaved similarly to the granule cells obtained from normal rat brain. 2. In both cases there were progressive losses of in vitro growing ability of the granule cells with the age of the animal and it became impossible to grow them when derived from 21 days or older animals. 3. A marked decrease in cell surface GM1 was observed when the cells were maintained under thyroid hormone-deficient conditions in culture. 4. Anti-GM1 antibody was found to inhibit significantly the migration of granule cells along the astrocyte fibers. 5. These results indicate that GM1 has an important role in thyroid hormone-dependent postnatal brain maturation in rat.
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94
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Chatterjee D, Chakraborty M, Leit M, Neff L, Jamsa-Kellokumpu S, Fuchs R, Bartkiewicz M, Hernando N, Baron R. The osteoclast proton pump differs in its pharmacology and catalytic subunits from other vacuolar H(+)-ATPases. J Exp Biol 1992; 172:193-204. [PMID: 1491225 DOI: 10.1242/jeb.172.1.193] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Osteoclasts are multinucleated cells derived from the mononuclear phagocyte system in the hematopoietic bone marrow. Their function is to resorb bone during skeletal growth and remodeling. They perform this function by acidifying an enclosed extracellular space, the bone resorbing compartment. Analysis of proton transport by inside-out vesicles derived from highly purified chicken osteoclast membranes has revealed the presence of a novel type of multisubunit vacuolar-like H(+)-ATPase. Unlike H(+)-ATPases derived from any other cell type or organelle, proton transport and ATPase activity in osteoclast vesicles are sensitive to two classes of inhibitors, namely V-ATPase inhibitors [N-ethyl-maleimide (NEM) and bafilomycin A1] and vanadate (IC50 100 mumol l-1), an inhibitor previously found to affect only P-ATPases. The osteoclast V-ATPase morphologically resembles vacuolar proton pumps and contains several vacuolar-like subunits (115 x 10(3), 39 x 10(3) and 16 x 10(3)M(r)), demonstrated by Western blot analysis. Subunits A and B of the catalytic domain of the enzyme, however, differ from that of other V-ATPases. In osteoclasts, subunit A has an M(r) of 63 x 10(3) instead of 67 x 10(3)-70 x 10(3); in contrast, monocytes, macrophages and kidney microsomes, which contain a vanadate-insensitive H(+)-ATPase, express the classical subunit A (70 x 10(3)M(r)). Moreover, two types of 57 x 10(3)-60 x 10(3)M(r) B subunits are also found: they are differentially recognized by antibodies and one is expressed predominantly in osteoclasts and the other in bone marrow cells and in kidney microsomes. Preliminary cloning data have indicated that the B subunit expressed in osteoclasts may be similar to the brain isoform. The osteoclast proton pump may, therefore, constitute a novel class of V-ATPase, with a unique pharmacology and specific isoforms of two subunits in the catalytic portion of the enzyme.
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95
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Su Y, Chakraborty M, Nathanson MH, Baron R. Differential effects of the 3',5'-cyclic adenosine monophosphate and protein kinase C pathways on the response of isolated rat osteoclasts to calcitonin. Endocrinology 1992; 131:1497-502. [PMID: 1324163 DOI: 10.1210/endo.131.3.1324163] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Calcitonin (CT) activates both the cAMP and the protein kinase C (PKC) pathways in the kidney cell line LLC-PK1. Although CT also activates cAMP in osteoclasts, its effects on PKC in this cell type are unknown. In order to determine whether the response of osteoclasts to CT also involves the PKC pathway, the effects of activators and inhibitors of PKC on bone resorption and cell surface area were analyzed in isolated rat osteoclasts. As expected, CT inhibited in a dose-dependent manner bone resorption by rat osteoclasts cultured for 24 h on devitalized bovine bone slices and this effect could be mimicked by cAMP. The inhibitory effect of CT could however also be mimicked by phorbol-12,13-dibutyrate (PDBu) and blocked by the PKC inhibitor sphingosine, as well as by the less specific inhibitors H7 and H8, none of which had detectable effects in the absence of CT. No changes in the number of attached osteoclasts were observed under any of these conditions. These results indicate that CT activates PKC in osteoclasts and that this activation, like the activation of cAMP-dependent protein kinase, leads to an inhibition of bone resorption. Quantitative time-lapse videomicroscopy showed that the CT-induced retraction of osteoclasts also involved activation of the PKC pathway and could therefore be induced by phorbol esters. In contrast, (Bu)2 cAMP (1-200 microM) failed to induce rapid cell retraction. It is concluded that, in osteoclasts, CT receptors are coupled to both the cAMP-dependent protein kinase and the PKC pathways. Although these two second messengers can have additive inhibitory effects on bone resorption, only activation of the PKC pathway induces rapid cell retraction. These two effects of calcitonin on osteoclasts are therefore independent and may be functionally unrelated.
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96
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Chatterjee D, Chakraborty M, Leit M, Neff L, Jamsa-Kellokumpu S, Fuchs R, Baron R. Sensitivity to vanadate and isoforms of subunits A and B distinguish the osteoclast proton pump from other vacuolar H+ ATPases. Proc Natl Acad Sci U S A 1992; 89:6257-61. [PMID: 1385872 PMCID: PMC49479 DOI: 10.1073/pnas.89.14.6257] [Citation(s) in RCA: 124] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Analysis of proton (H+) transport by inside-out vesicles derived from highly purified chicken osteoclast (OC) membranes has revealed the presence of a newly discovered type of vacuolar H+ ATPase (V-ATPase). Unlike vesicles derived from any other cell type or organelle, H+ transport in OC-derived vesicles is sensitive to V-ATPase inhibitors (N-ethylmaleimide and Bafilomycin A1) and vanadate (IC50, 100 microM), an inhibitor previously found to affect only P-type ATPases. The OC H+ ATPase contains several V-like subunits (115, 39, and 16 kDa) but subunits A and B of the catalytic domain of the enzyme differ from that of other V-ATPases. In OCs, subunit A has a mass of 63 kDa instead of the 67-70 kDa expressed in monocytes, macrophages, and kidney microsomes, which contain a vanadate-insensitive H+ ATPase. Moreover, two types of 57- to 60-kDa B subunits are also found: one is expressed predominantly in OCs and the other is expressed in kidney microsomes. The OC H+ pump may therefore constitute a class of H+ ATPase with a unique pharmacology and specific isoforms of two subunits in the catalytic portion of the enzyme. This H+ ATPase is involved in resorption of bone and may be expressed in a cell-specific manner, thereby opening possibilities for therapeutic intervention.
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97
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Chandra N, Chakraborty M. Auger electron spectroscopy of molecules: Theory for spin polarization following photoabsorption. J Chem Phys 1992. [DOI: 10.1063/1.463621] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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98
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Chatterjee D, Chakraborty M, Anderson GM. Differentiation of Neuro-2a neuroblastoma cells by an antibody to GM3 ganglioside. Brain Res 1992; 583:31-44. [PMID: 1324094 DOI: 10.1016/s0006-8993(10)80007-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A monoclonal antibody against GM3 ganglioside (GM3Ab) was found to trigger differentiation of Neuro-2a cells in culture. The differentiation of Neuro-2a cells by GM3Ab was accompanied by increased levels of intracellular serotonin and amino acid neurotransmitters viz. aspartate, glutamate, glutamine, glycine and taurine. Further study indicated that the increase in the serotonin level was not due to a higher rate of serotonin synthesis but rather to a higher rate of active transport of serotonin from the medium. Studies on the cell surface gangliosides revealed that unlike the proliferating cells, the GM3Ab-mediated differentiated cells contained higher gangliosides in addition to GM3 and GM2 gangliosides. Analysis of total cellular proteins indicated the appearance of a 25 kDa protein, pI 5.4, in the GM3Ab-treated cells--a small amount of this protein was observed in dibutyryl cAMP (Bt2cAMP)-treated cells, however, the protein was totally absent in the 5-bromo-2'-deoxyuridine (BrdU)-treated cells. Investigation of the mode of action of GM3Ab indicated that the cellular differentiation was due to increased cAMP accumulation resulting from an increase in the adenylate cyclase activity. Further studies with different agents affecting protein kinase C (PKC) activity and direct assay of PKC ruled out the possibility that GM3Ab mediated its effect via PKC. This GM3Ab-induced differentiation could be inhibited by protein kinase A (PKA) inhibitor, H8, but could not be inhibited by sphingosine, an inhibitor of PKC. Pertussis toxin could mimic the effect of GM3Ab, suggesting that GM3Ab caused the elevation in the adenylate cyclase activity by reducing the Gi-protein inhibition of the adenylate cyclase. The data suggests that GM3Ab, after interaction with cell surface GM3, elevated intracellular cAMP level by withdrawing the inhibitory effect of some undefined factor(s) present in culture medium which normally keeps adenylate cyclase activity low through activation of Gi-protein.
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99
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Biswas T, Chakraborty M, Naskar K, Ghosh DK, Ghosal J. Anemia in experimental visceral leishmaniasis in hamsters. J Parasitol 1992; 78:140-2. [PMID: 1310731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Experimental infection of hamsters with Leishmania donovani caused visceral leishmaniasis in which hematological changes occurred. The infected hamsters were anemic and reticulocyte counts were high. No significant change in the serum erythropoietin level was noted. Red cell membrane Na(+)-K(+)-ATPase and acetylcholinesterase activities increased. Osmotic fragility of the erythrocytes from infected animals increased. The level of 2,3-diphosphoglycerate of the red cells increased with the degree of anemia.
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100
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Gupta SK, Chakraborty M, Mitra K. Serum angiotensin converting enzyme in respiratory diseases. THE INDIAN JOURNAL OF CHEST DISEASES & ALLIED SCIENCES 1992; 34:19-24. [PMID: 1325944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
More than 1700 estimations of serum angiotensin converting enzyme (SACE) were undertaken, mostly in respiratory disorders, to assess its value as a specific and/or a sensitive indicator of different diseases. Though highest levels were found in lepromatous leprosy consistently, it was also found almost always elevated in active stages of sarcoidosis. Since it is raised in a variety of respiratory disorders, it is not a specific diagnostic test. It is, however, a fairly sensitive index of disease activity in sarcoidosis whether on treatment or not. Sudden elevation, after a prolonged period of low or normal values may indicate relapse in sarcoidosis.
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