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Gangopadhyay A, Sparks NJ, Toumi R, Seshadri AK. Risk assessment of wind droughts over India. CURR SCI INDIA 2022. [DOI: 10.18520/cs/v122/i10/1145-1153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Das P, Mukherjee R, Pathak D, Gangopadhyay A, Halder S, Singh SK. Tension pneumoperitoneum: a very rare complication of acute gangrenous appendicitis. Ann R Coll Surg Engl 2016; 98:e197-e199. [PMID: 27652797 DOI: 10.1308/rcsann.2016.0240] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Tension pneumoperitoneum is a very rare consequence of acute gangrenous appendicitis. We report a case of a 32-year-old woman who presented with abdominal pain, progressively increasing abdominal distension, profound hemodynamic instability and ventilatory compromise. The diagnosis of tension pneumoperitoneum was confirmed by computed tomography, which showed compression of the intra-abdominal viscera and liver (saddlebag sign) by a large volume of intraperitoneal free air. Urgent needle decompression was done as an emergency measure. Exploratory laparotomy, planned due to persistent peritonitis, revealed gangrenous appendicitis with perforation near its base. Appendicectomy with excision of gangrenous portion of caecum was performed. The purpose of the reporting this case is to highlight that the tension pneumoperitoneum can be, very rarely, associated with gangrenous appendicitis and timely diagnosis is very important for the emergency management of this deadly condition.
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Affiliation(s)
- P Das
- RG Kar Medical College , Kolkata, West Bengal , India
| | - R Mukherjee
- RG Kar Medical College , Kolkata, West Bengal , India
| | - D Pathak
- RG Kar Medical College , Kolkata, West Bengal , India
| | | | - S Halder
- RG Kar Medical College , Kolkata, West Bengal , India
| | - S K Singh
- RG Kar Medical College , Kolkata, West Bengal , India
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Gandhi T, Kadam K, Gupte A, Gangopadhyay A, Sharma R. Alkyl Nitrites: Novel Reagents for One-Pot Synthesis of 3,5-Disubstituted Isoxazoles from Aldoximes and Alkynes. SYNTHESIS-STUTTGART 2016. [DOI: 10.1055/s-0035-1561464] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
| | | | - Amol Gupte
- Department of Medicinal Chemistry, Piramal Enterprises Limited
| | - A. Gangopadhyay
- Department of Medicinal Chemistry, Piramal Enterprises Limited
| | - Rajiv Sharma
- Department of Medicinal Chemistry, Piramal Enterprises Limited
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Pathak D, Mukherjee R, Das P, Pathak D, Gangopadhyay A, Das S. Traumatic abdominal wall hernia with concealed colonic perforation. Ann R Coll Surg Engl 2016; 98:e133-5. [PMID: 27241601 DOI: 10.1308/rcsann.2016.0178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Traumatic abdominal wall hernia (TAWH) is a rare clinical entity in terms of aetiology. It occurs following a blunt abdominal injury with energy high enough to cause disruption of the musculoaponeurotic layer but not the elastic skin layer. It is often associated with underlying intra-abdominal injuries, which can be diagnosed either clinically or radiologically. We report a case of TAWH in a young man with associated large bowel transection, which remained undiagnosed in the preoperative period owing to its masked features. He was managed surgically, with no recurrence to date. Considering the high volume of blunt abdominal trauma cases that present to the accident and emergency department, only few cases of TAWH have been reported in the literature. Confusion still exists regarding the timing and mode of management of this condition.
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Affiliation(s)
- D Pathak
- RG Kar Medical College , Kolkata , India
| | | | - P Das
- RG Kar Medical College , Kolkata , India
| | | | | | - S Das
- RG Kar Medical College , Kolkata , India
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Khan MW, Priyamvada S, Khan SA, Khan S, Gangopadhyay A, Yusufi ANK. Fish/flaxseed oil protect against nitric oxide-induced hepatotoxicity and cell death in the rat liver. Hum Exp Toxicol 2015; 35:302-11. [PMID: 25964379 DOI: 10.1177/0960327115586207] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Sodium nitroprusside (SNP) is an antihypertensive drug with proven toxic effects attributed mainly to the production of nitric oxide (NO). Polyunsaturated fatty acids (PUFAs) are widely regarded as functional foods and have been shown to ameliorate the harmful effects of many toxicants. This study examined whether feeding of fish oil (FO)/flaxseed oil (FXO) would have any protective effect against SNP-induced hepatotoxicity and cell death. Male Wistar rats were fed either on normal diet or with 15% FO/FXO for 15 days, following which SNP (1.5 mg/kg body weight) was administered intraperitoneally for 7 days. Animals were killed after treatment, and livers were collected for further analysis. We observed that SNP significantly elevated tissue nitrite levels and lipid peroxidation (LPO) with concomitant perturbation in antioxidant defense systems accompanied with dysregulated glucose metabolism and pronounced cellular death. FO/FXO supplementation to SNP-treated rats caused reversal of tissue injury/cell death and markedly decreased LPO and improved antioxidant defense systems. FO/FXO appear to protect against SNP-induced hepatotoxicity by improving energy metabolism and antioxidant defense mechanism.
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Affiliation(s)
- M W Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh, India Cell Biology and Physiology Division, Council of Scientific and Industrial Research (CSIR)-Indian Institute of Chemical Biology, Jadavpur, Kolkata, West Bengal, India
| | - S Priyamvada
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh, India Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - S A Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh, India SVKMs Mithibai College, Bhakti Vedanta Marg, Vile Parle (W), Mumbai, Maharashtra, India
| | - S Khan
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - A Gangopadhyay
- Flow Cytometry Technician, CSIR-Indian Institute of Chemical Biology, BD FACS
| | - A N K Yusufi
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
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Adhikari K, Pal S, Chakraborty B, Mukherjee SN, Gangopadhyay A. Assessment of phenol infiltration resilience in soil media by HYDRUS-1D transport model for a waste discharge site. Environ Monit Assess 2014; 186:6417-6432. [PMID: 24929358 DOI: 10.1007/s10661-014-3864-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 06/06/2014] [Indexed: 06/03/2023]
Abstract
The movement of contaminants through soil imparts a variety of geo-environmental problem inclusive of lithospheric pollution. Near-surface aquifers are often vulnerable to contamination from surface source if overlying soil possesses poor resilience or contaminant attenuation capacity. The prediction of contaminant transport through soil is urged to protect groundwater from sources of pollutants. Using field simulation through column experiments and mathematical modeling like HYDRUS-1D, assessment of soil resilience and movement of contaminants through the subsurface to reach aquifers can be predicted. An outfall site of effluents of a coke oven plant comprising of alarming concentration of phenol (4-12.2 mg/L) have been considered for studying groundwater condition and quality, in situ soil characterization, and effluent characterization. Hydrogeological feature suggests the presence of near-surface aquifers at the effluent discharge site. Analysis of groundwater of nearby locality reveals the phenol concentration (0.11-0.75 mg/L) exceeded the prescribed limit of WHO specification (0.002 mg/L). The in situ soil, used in column experiment, possess higher saturated hydraulic conductivity (KS = 5.25 × 10(-4) cm/s). The soil containing 47 % silt, 11 % clay, and 1.54% organic carbon content was found to be a poor absorber of phenol (24 mg/kg). The linear phenol adsorption isotherm model showed the best fit (R(2) = 0.977, RMSE = 1.057) to the test results. Column experiments revealed that the phenol removal percent and the length of the mass transfer zone increased with increasing bed heights. The overall phenol adsorption efficiency was found to be 42-49%. Breakthrough curves (BTCs) predicted by HYDRUS-1D model appears to be close fitting with the BTCs derived from the column experiments. The phenol BTC predicted by the HYDRUS-1D model for 1.2 m depth subsurface soil, i.e., up to the depth of groundwater in the study area, showed that the exhaustion point was reached within 12 days of elapsed time. This clearly demonstrated poor attenuation capacity of the soil to retard migration of phenol to the groundwater from the surface outfall site. Suitable liner, based on these data, may be designed to inhibit subsurface transport of phenol and thereby to protect precious groundwater from contamination.
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Affiliation(s)
- K Adhikari
- Department of Earth and Environmental Studies, National Institute of Technology, Durgapur, India,
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Abstract
Disseminated tuberculosis is a common mode of presentation of tuberculosis in patients both with and without HIV/AIDS in India. However, primary multidrug resistance in disseminated tuberculosis involving only the extrapulmonary sites in an immunocompetent adult is rare. Here, we report a case of a 19-year-old man who had disseminated tuberculosis involving left pleura, pericardium, peritoneum and intraabdominal lymph nodes. He was initially taking WHO category I antituberculous drugs, but was not responding in spite of 5 months of chemotherapy. Culture of the pleural biopsy specimen grew Mycobacterium tuberculosis which was resistant to isoniazid and rifampicin. He was put on therapy for multidrug resistant tuberculosis,following 24 months of chemotherapyhe had an uneventful recovery.
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Affiliation(s)
- S K Das
- Department of Respiratory Medicine, Medical College, Kolkata, West Bengal, India
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Saha S, Gangopadhyay A, Chatterjee P, Ghosh K. 613 poster COMPARISON BETWEEN VOLUME AND GEOMETRICAL OPTIMIZATION IN CT BASED HDR BREAST IMPLANTS AND ITS IMPACT ON COSMETIC OUTCOME. Radiother Oncol 2011. [DOI: 10.1016/s0167-8140(11)70735-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Gangopadhyay A, Saha S. 458 Evaluation of concomitant radio-endocrine therapy as primary treatment modality for elderly receptor positive locally advanced breast cancer patients. EJC Suppl 2010. [DOI: 10.1016/s1359-6349(10)70479-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Saha S, Gangopadhyay A. 240 Postmastectomy adjuvant radiotherapy in patients with less than four axillary lymph nodes: a retrospective analysis. EJC Suppl 2010. [DOI: 10.1016/s1359-6349(10)70266-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Saha S, Ghosh Dastidar A, Gangopadhyay A, Ghorai S. Evaluation of Hypofractionated Adjuvant Radiotherapy for Early Breast Cancer: A Prospective Randomized Study. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Gangopadhyay A, Saha S. Evaluation Of External Beam Parametrial Boost In Locally Advanced Cervix Cancer–An Interim Report. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Saha S, Gangopadhyay A, Ghorai S. 5028 Neoadjuvant concomitant radio-endocrine therapy for locally- advanced receptor positive elderly breast cancer: an Indian experience. EJC Suppl 2009. [DOI: 10.1016/s1359-6349(09)70920-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Banerjee D, Chakraborty SK, Bhattacharyya S, Gangopadhyay A. Attitudinal response towards road traffic noise in the industrial town of Asansol, India. Environ Monit Assess 2009; 151:37-44. [PMID: 18369730 DOI: 10.1007/s10661-008-0247-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Accepted: 02/29/2008] [Indexed: 05/16/2023]
Abstract
The major objective of the investigation was to evaluate the road traffic noise and its likely impacts on the local community of Asansol city (West Bengal, India) by monitoring and modeling. The attitudinal response of local population due to existing vehicular noise is presented in the paper. Noise and Attitudinal Survey was conducted at 25 locations. A total of 869 individuals were surveyed. The relationship between traffic noise levels and annoyance was studied using correlation, linear and multiple linear regressions analysis. The average L(dn) value was 73.28 +/- 8.51 dB(A) (55.1-87.3); The Traffic Noise Index (TNI) was 80.62 +/- 15.88 dB(A) (49.4-115.8). The mean value of percent of population Highly Annoyed (%HA) due to road traffic noise was 26.50 +/- 3.37 (19.44-33.2), whereas the mean dissatisfaction score (MDS) was 2.96 +/- 0.90 (1.04-4.45). Annoyance modeling was also performed based on field data. It can be said that Noise values gives desirable annoyance predicting values in comparison to vehicular data.
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Affiliation(s)
- D Banerjee
- Department of Environment and Water Management, B.B. College, Ushagram, Asansol, Burdwan, 713303, West Bengal, India.
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Banerjee D, Chakraborty SK, Bhattacharyya S, Gangopadhyay A. Evaluation and analysis of road traffic noise in Asansol: an industrial town of eastern India. Int J Environ Res Public Health 2009; 5:165-71. [PMID: 19139535 PMCID: PMC3699987 DOI: 10.3390/ijerph5030165] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The objectives of the study were to monitor and assess the road traffic noise in its spatial-temporal aspect in an urban area. The paper discusses the observations, results and their interpretation based on the study. Noise recordings from site, collected from April 2006 to March 2006, were used for statistical analysis and generation of various noise indices. Noise maps were also created for impact analysis and formulation of Noise Risk Zones. Mean Ldn value ranged between 55.1 and 87.3 dB (A). Day time Leq level ranged between 51.2 and 89.0 dB (A), where it ranged between 43.5 and 81.9 dB (A) during night. The study reveals that present noise level in all the locations exceeds the limit prescribed by CPCB. Based on the finding it can be said that the population in this industrial town are exposed to significantly high noise level, which is caused mostly due to road traffic.
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Affiliation(s)
- D Banerjee
- Department of Environment & Water Management, B. B. College, Ushagram, Asansol-713303, West Bengal, India.
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Saha S, Gangopadhyay A, Basu A. 0113 Hypofractionated adjuvant radiotherapy for early breast cancer: A prospective randomized study. Breast 2009. [DOI: 10.1016/s0960-9776(09)70154-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Moser AJ, Gangopadhyay A, Bradbury NA, Peters KW, Frizzell RA, Bridges RJ. Electrogenic bicarbonate secretion by prairie dog gallbladder. Am J Physiol Gastrointest Liver Physiol 2007; 292:G1683-94. [PMID: 17363467 DOI: 10.1152/ajpgi.00268.2006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Pathological rates of gallbladder salt and water transport may promote the formation of cholesterol gallstones. Because prairie dogs are widely used as a model of this event, we characterized gallbladder ion transport in animals fed control chow by using electrophysiology, ion substitution, pharmacology, isotopic fluxes, impedance analysis, and molecular biology. In contrast to the electroneutral properties of rabbit and Necturus gallbladders, prairie dog gallbladders generated significant short-circuit current (I(sc); 171 +/- 21 microA/cm(2)) and lumen-negative potential difference (-10.1 +/- 1.2 mV) under basal conditions. Unidirectional radioisotopic fluxes demonstrated electroneutral NaCl absorption, whereas the residual net ion flux corresponded to I(sc). In response to 2 microM forskolin, I(sc) exceeded 270 microA/cm(2), and impedance estimates of the apical membrane resistance decreased from 200 Omega.cm(2) to 13 Omega.cm(2). The forskolin-induced I(sc) was dependent on extracellular HCO(3)(-) and was blocked by serosal 4,4'-dinitrostilben-2,2'-disulfonic acid (DNDS) and acetazolamide, whereas serosal bumetanide and Cl(-) ion substitution had little effect. Serosal trans-6-cyano-4-(N-ethylsulfonyl-N-methylamino)-3-hydroxy-2,2-dimethyl-chroman and Ba(2+) reduced I(sc), consistent with the inhibition of cAMP-dependent K(+) channels. Immunoprecipitation and confocal microscopy localized cystic fibrosis transmembrane conductance regulator protein (CFTR) to the apical membrane and subapical vesicles. Consistent with serosal DNDS sensitivity, pancreatic sodium-bicarbonate cotransporter protein pNBC1 expression was localized to the basolateral membrane. We conclude that prairie dog gallbladders secrete bicarbonate through cAMP-dependent apical CFTR anion channels. Basolateral HCO(3)(-) entry is mediated by DNDS-sensitive pNBC1, and the driving force for apical anion secretion is provided by K(+) channel activation.
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Affiliation(s)
- A James Moser
- Univ. of Pittsburgh School of Medicine, 497 Scaife Hall; 3550 Terrace St.; Pittsburgh, PA 15261, USA.
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Gangopadhyay A, Jolly PE. Lack of enhancement of caprine arthritis encephalitis virus infection in monocyte-derived macrophage cultures by sera from goats that developed severe arthritis after vaccination and virus challenge. Cell Mol Biol (Noisy-le-grand) 2003; 49:1177-82. [PMID: 14682401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
We examined sera from goats that developed more rapid and severe clinical disease after vaccination with inactivated caprine arthritis encephalitis virus (CAEV) and virus challenge for CAEV infection-enhancing antibodies. Sera from one control and two vaccinated goats were examined for neutralization or enhancement of virus infection in caprine macrophages. Macrophage cultures were incubated with virus-serum mixtures, then washed and fed with fresh media and incubated. Culture fluid was collected at days 2,4 and 8 post-infection and assayed for reverse transcriptase (RT) activity. Serum from one of the vaccinated goats neutralized virus at 10(-2) and 10(-3) dilutions (p = 0.045 and p = 0.020, respectively). The neutralizing effect was lost at higher dilutions (10(-4) and 10(-5)) of the serum, but no enhancement of infection was seen. Serum from the other vaccinated goat did not show any significant neutralizing effect at either 10(-2) or 10(-3) dilutions and increased infection (40% or greater) at higher dilutions, but the increases were not statistically significant. Therefore, there was no evidence of virus infection-enhancing activity in these sera that would suggest that the severe disease experienced by the vaccinated animals was due to serum enhancement of infection. Alternately, the severe arthritis observed could have resulted from the pro-inflammatory activities of cytokines and chemokines produced by macrophages upon phagocytosis, or receptor-mediated uptake of CAEV-antibody complexes.
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Affiliation(s)
- A Gangopadhyay
- Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, 1665 University Boulevard, RPHB 217, Birmingham, AL 35294-0022, USA
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Ng CJ, Wadleigh DJ, Gangopadhyay A, Hama S, Grijalva VR, Navab M, Fogelman AM, Reddy ST. Paraoxonase-2 is a ubiquitously expressed protein with antioxidant properties and is capable of preventing cell-mediated oxidative modification of low density lipoprotein. J Biol Chem 2001; 276:44444-9. [PMID: 11579088 DOI: 10.1074/jbc.m105660200] [Citation(s) in RCA: 355] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The oxidation of apolipoprotein B-containing lipoproteins and cell membrane lipids is believed to play an integral role in the development of fatty streak lesions, an initial step in atherogenesis. We have previously shown that two antioxidant-like enzymes, paraoxonase (PON)-1 and PON3, are high density lipoprotein-associated proteins capable of preventing the oxidative modification of low density lipoprotein (LDL) (Reddy, S. T., Wadleigh, D. J., Grijalva, V., Ng, C., Hama, S., Gangopadhyay, A., Shih, D. M., Lusis, A. J., Navab, M., and Fogelman, A. M. (2001) Arterioscler. Thromb. Vasc. Biol. 21, 542-547). In the present study, we demonstrate that PON2 (i) is not associated with high density lipoprotein; (ii) has antioxidant properties; and (iii) prevents LDL lipid peroxidation, reverses the oxidation of mildly oxidized LDL (MM-LDL), and inhibits the ability of MM-LDL to induce monocyte chemotaxis. The PON2 protein was overexpressed in HeLa cells using the tetracycline-inducible ("Tet-On") system, and its antioxidant capacity was measured in a fluorometric assay. Cells that overexpressed PON2 showed significantly less intracellular oxidative stress following treatment with hydrogen peroxide or oxidized phospholipid. Moreover, cells that overexpressed PON2 were also less effective in oxidizing and modifying LDL and, in fact, were able to reverse the effects of preformed MM-LDL. Our results suggest that PON2 possesses antioxidant properties similar to those of PON1 and PON3. However, in contrast to PON1 and PON3, PON2 may exert its antioxidant functions at the cellular level, joining the host of intracellular antioxidant enzymes that protect cells from oxidative stress.
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Affiliation(s)
- C J Ng
- Atherosclerosis Research Unit, University of California, Los Angeles, California 90095-1679, USA
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Reddy ST, Wadleigh DJ, Grijalva V, Ng C, Hama S, Gangopadhyay A, Shih DM, Lusis AJ, Navab M, Fogelman AM. Human paraoxonase-3 is an HDL-associated enzyme with biological activity similar to paraoxonase-1 protein but is not regulated by oxidized lipids. Arterioscler Thromb Vasc Biol 2001; 21:542-7. [PMID: 11304470 DOI: 10.1161/01.atv.21.4.542] [Citation(s) in RCA: 259] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Paraoxonase-1 (PON1) is a secreted protein associated primarily with high density lipoprotein (HDL) and participates in the prevention of low density lipoprotein (LDL) oxidation. Two other paraoxonase (PON) family members, namely, PON2 and PON3, have been identified. In this study, we report the cloning and characterization of the human PON3 gene from HepG2 cells. Tissue Northern analysis identifies an approximately 1.3-kb transcript for PON3 primarily in the liver. PON3-specific peptide antibodies detect an approximately 40-kDa protein associated with HDL and absent from LDL. Pretreatment of cultured human aortic endothelial cells with supernatants from HeLa Tet On cell lines overexpressing PON3 prevents the formation of mildly oxidized LDL and inactivates preformed mildly oxidized LDL. In contrast to PON1, PON3 is not active against the synthetic substrates paraoxon and phenylacetate. Furthermore, PON3 expression is not regulated in HepG2 cells by oxidized phospholipids and is not regulated in the livers of mice fed a high-fat atherogenic diet.
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Affiliation(s)
- S T Reddy
- Atherosclerosis Research Unit, Division of Cardiology, Department of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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Forgionne GA, Gangopadhyay A, Adya M. Cancer surveillance using data warehousing, data mining, and decision support systems. Top Health Inf Manage 2000; 21:21-34. [PMID: 11010367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
This article discusses how data warehousing, data mining, and decision support systems can reduce the national cancer burden or the oral complications of cancer therapies, especially as related to oral and pharyngeal cancers. An information system is presented that will deliver the necessary information technology to clinical, administrative, and policy researchers and analysts in an effective and efficient manner. The system will deliver the technology and knowledge that users need to readily: (1) organize relevant claims data, (2) detect cancer patterns in general and special populations, (3) formulate models that explain the patterns, and (4) evaluate the efficacy of specified treatments and interventions with the formulations. Such a system can be developed through a proven adaptive design strategy, and the implemented system can be tested on State of Maryland Medicaid data (which includes women, minorities, and children).
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Affiliation(s)
- G A Forgionne
- Information Systems Department, University of Maryland Baltimore County, Catonsville, USA
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Gangopadhyay A. Surgery Without Gloves - a Classic in Dermato-surgery?(le). Indian J Dermatol Venereol Leprol 2000; 66:220. [PMID: 20877084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- A Gangopadhyay
- Dept. of Dermatology, RKM Seva Pratisthan, Calcutta - 700 026, India
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Zhou X, Thamotharan M, Gangopadhyay A, Serdikoff C, Adibi SA. Characterization of an oligopeptide transporter in renal lysosomes. Biochim Biophys Acta 2000; 1466:372-8. [PMID: 10825457 DOI: 10.1016/s0005-2736(00)00201-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Renal lysosomes play a major role in catabolism of plasma proteins. Final products of this catabolism include dipeptides and tripeptides that must be exported to the cytosol for hydrolysis. The aim of the present study was to determine whether an oligopeptide transporter is present in the renal lysosomal membrane that could mediate this export. The existence of an oligopeptide transporter was probed with the uptake of glycylglutamine (Gly-Gln) by membrane vesicles prepared from renal lysosomes. Kinetic analysis showed the presence of a single transporter with a K(m) of 8.77 mM for the uptake of Gly-Gln. The Gly-Gln uptake was energized by the imposition of an inwardly directed proton gradient (pH(out) 5.0/pH(in) 7.3) and membrane potential (outside positive/inside negative) resulting in overshoot. The Gly-Gln uptake was inhibited by the presence of dipeptides and tripeptides, but not amino acids. Western blot analysis of lysosomal membrane proteins with Pept-1 (an oligopeptide transporter) antibody as the probe showed the presence of an immunoreactive protein. This immunoreaction was abolished when the antiserum was preabsorbed with the Pept-1 epitope (0.5 microg/ml). In conclusion, the present data show the existence of a low-affinity dipeptide transporter in the renal lysosomal membrane that appears to belong to the Pept family of transporters. The function of this transporter appears to be to prevent accumulation of dipeptides in renal lysosomes.
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Affiliation(s)
- X Zhou
- Clinical Nutrition Research Unit, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
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Forgionne GA, Gangopadhyay A, Klein JA, Eckhardt R. A decision technology system for health care electronic commerce. Top Health Inf Manage 1999; 20:31-41. [PMID: 10539421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Mounting costs have escalated the pressure on health care providers and payers to improve decision making and control expenses. Transactions to form the needed decision data will routinely flow, often electronically, between the affected parties. Conventional health care information systems facilitate flow, process transactions, and generate useful decision information. Typically, such support is offered through a series of stand-alone systems that lose much useful decision knowledge and wisdom during health care electronic commerce (e-commerce). Integrating the stand-alone functions can enhance the quality and efficiency of the segmented support, create synergistic effects, and augment decision-making performance and value for both providers and payers. This article presents an information system that can provide complete and integrated support for e-commerce-based health care decision making. The article describes health care e-commerce, presents the system, examines the system's potential use and benefits, and draws implications for health care management and practice.
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Affiliation(s)
- G A Forgionne
- Information Systems Department, University of Maryland, Baltimore County, Catonsville, USA
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Abstract
Kupffer cells, a majority of the body's fixed macrophages, are a major site of bacterial lipopolysaccharide (LPS) metabolism and are mediators in the body's response to sepsis. Uptake of LPS is different in Kupffer cells than other macrophages. Signal transduction in other macrophages in response to LPS involves phosphorylation of proteins in the 50-60 kDa range. We hypothesized that Kupffer cells may have unique signal transduction pathways in response to LPS. Rat Kupffer cells were exposed to LPS (1 microgram/mL) for varying times ranging from 15 to 90 min. Cell lysates were Western blotted using an anti-phosphotyrosine antibody. The blots showed an increase in the amount of tyrosine phosphorylation on two proteins of 119 kDa and 83 kDa. The effects of varying LPS concentration (1 ng/mL-1 microgram/mL) showed an increasing amount of phosphorylation with increasing LPS concentration. To associate the importance of tyrosine phosphorylation in the response of Kupffer cells to LPS, the tyrosine kinase inhibitors, tyrphostin, lavendustin, and genisten were used to study the effects of inhibiting phosphorylation on TNF-alpha production. Kupffer cells were preincubated in the presence of the inhibitor and exposed to LPS (1 microgram/mL). TNF-alpha was measured in the conditioned media by ELISA. A 70% or greater decrease in TNF-alpha production was observed. When phagocytosis of latex beads by rat Kupffer cells was measured in vivo using intravital video microscopy, LPS treatment significantly increased uptake. This increase in phagocytosis was inhibited by tyrphostin. These results show what may be unique phosphorylation events in Kupffer cells that are related to LPS induced production of TNF-alpha.
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Affiliation(s)
- R L Schultze
- Department of Surgery, Beth Israel-Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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Gangopadhyay A, Lazure DA, Thomas P. Adhesion of colorectal carcinoma cells to the endothelium is mediated by cytokines from CEA stimulated Kupffer cells. Clin Exp Metastasis 1998; 16:703-12. [PMID: 10211983 DOI: 10.1023/a:1006576627429] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We hypothesize that a major factor regulating hepatic metastasis is the ability of CEA (carcinoembryonic antigen) producing colorectal carcinomas to activate Kupffer cells. CEA and NCA (nonspecific cross-reacting antigen) bind to an 80 kDa Kupffer cell receptor by the peptide sequence PELPK and stimulate cytokine production. Cytokines induce sinusoidal endothelial cells to express intercellular adhesion molecules and increase adhesion of the tumor cells and retention in the liver. In this study human Kupffer cells were activated in vitro with CEA, NCA, and the peptide PELPK. This resulted in release of IL-1beta, TNF-alpha and IL-6. CEA non-producing MIP-101 colon carcinoma cells labeled with 51Cr were incubated on monolayers of ECV-304 human umbilical vein endothelial cells treated with these Kupffer cell derived cytokines or with comparable recombinant human (rH) cytokines. Specific antibodies to the adhesion molecules ICAM-1, VCAM-1, E-selectin and beta2integrin were used to block their functions. A significant enhancement in the adhesion of colorectal carcinoma cells occurred when endothelial cells were stimulated with a very low concentration of Kupffer-cell derived cytokines. Activated endothelium demonstrated significant up-regulation primarily of ICAM-1. The adhesion was blocked by an antibody to ICAM-1. A combination of Kupffer-cell derived cytokines was more effective than IL-1beta or TNF-alpha alone. IL-6 alone did not influence adhesion under our conditions. Our results suggest a mechanism for CEA in the modulation of colorectal carcinoma adhesion to the hepatic endothelium and its enhancement of metastatic potential.
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Affiliation(s)
- A Gangopadhyay
- Laboratory of Cancer Biology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA.
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Gangopadhyay A, Perera SP, Thomas P. Differential expression of alpha2,6-sialyltransferase in colon tumors recognized by a monoclonal antibody. Hybridoma (Larchmt) 1998; 17:117-23. [PMID: 9627051 DOI: 10.1089/hyb.1998.17.117] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
It has been reported that alpha2,6-sialyltransferase (alpha2,6-ST; E.C. 2.4.99.1) activity is associated with cellular differentiation. To define its role in colon carcinoma differentiation, we have generated murine monoclonal antibodies (MAb) against alpha2,6-sialyltransferase. The MAb, designated 6B9 of IgM isotype, showed strong reactivity with the purified and crude alpha2,6-ST by ELISA and dot blot assays. Western blotting with MAb 6B9 identified purified alpha2,6-ST of MW 47 kDa and the same MW protein from rat and human liver extracts. The MAb also reacted with two other liver proteins of approximate MW 65 and 100 kDa. Immunoperoxidase studies with formalin-fixed paraffin-embedded tissues showed that MAb 6B9 reacts with liver tissues, the staining of hepatocytes was granular and cytoplasmic. There was a distinct pattern of zonal distribution of this enzyme in hepatocytes located particularly in the portal areas of the liver corresponding to zone 1. Normal colon (100%) and hyperplastic polyps (100%) showed very weak to no reactivity. Adenomas (100%) demonstrated moderate reactivity, while the poor (33%), moderate (100%) and well-differentiated (80%) colon adenocarcinomas showed strong reactivity. Results suggest that alpha2,6-ST is associated with the differentiation state of colon tumors.
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Affiliation(s)
- A Gangopadhyay
- Laboratory of Cancer Biology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
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Edmiston KH, Gangopadhyay A, Shoji Y, Nachman AP, Thomas P, Jessup JM. In vivo induction of murine cytokine production by carcinoembryonic antigen. Cancer Res 1997; 57:4432-6. [PMID: 9331108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Carcinoembryonic antigen (CEA) may promote experimental metastasis through production of cytokines. The effect of systemic CEA on the production of proinflammatory cytokines was investigated in mice and compared to levels induced by lipopolysaccharide (LPS). Serum concentrations of interleukin (IL)-6 peaked 1 h after an i.v. CEA injection of 40 microg/mouse to 37-54% of the maximal level induced by a 1 microg/mouse injection of LPS in both normal and immunoincompetent mice. The CEA induction of IL-6 was a specific response, because the peptide PELPK (the pentapeptide on CEA that is the ligand for the CEA receptor on Kupffer cells) conjugated to albumin induced 30% of the maximal CEA response for IL-6, whereas the specificity control PELGK-conjugated albumin did not. IL-1alpha and tumor necrosis factor (TNF)-alpha levels after i.v. injection of CEA were only 3-5% of those induced by LPS. The IL-6 responses of mice pretreated with 100 microg/kg genistein were decreased by more than 40%. However, genistein inhibited the TNF-alpha response to LPS by 46% but increased the CEA-induced response by 300%. When murine Kupffer cells were stimulated with LPS or CEA in vitro, LPS increased tyrosine phosphorylation of a Mr 30,000 protein, whereas CEA decreased phosphorylation of a Mr 60,000 protein and did not increase phosphorylation of the Mr 30,000 protein. Thus, i.v. CEA stimulates production of IL-6 and TNF-alpha after binding to Kupffer cells through signal transduction pathways that appear to be different from those stimulated by LPS.
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Affiliation(s)
- K H Edmiston
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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Abstract
Carcinoembryonic antigen (CEA), an intercellular adhesion molecule and a mediator of hepatic metastasis, is processed by an 80 kDa receptor on murine and human Kupffer cells in the liver. Activation of rat Kupffer cells in vitro by CEA via the 80 kDa receptor produced cytokines IL-1alpha and TNF-alpha which involved tyrosine phosphorylation. The peak response of TNF-alpha was 5.6 times greater than the corresponding IL-1alpha response and was associated with enhanced tyrosine phosphorylation of 108 and 125 kDa proteins. Lipopolysaccharide (LPS) treatment, on the other hand, phosphorylated two major proteins with MW of 93 and 119 kDa associated with the loss of phosphorylation from a 125 kDa protein. Results demonstrate that CEA-induced IL-1alpha and TNF-alpha production involves tyrosine phosphorylation and the signaling in CEA treated cells is different than that seen with LPS stimulation.
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Affiliation(s)
- A Gangopadhyay
- Department of Surgery, Beth Israel-Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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Jolly PE, Gangopadhyay A, Chen S, Reddy PG, Weiss HL, Sapp WJ. Changes in the leukocyte phenotype profile of goats infected with the caprine arthritis encephalitis virus. Vet Immunol Immunopathol 1997; 56:97-106. [PMID: 9220584 DOI: 10.1016/s0165-2427(96)05726-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The proportions of different sub-populations of leukocytes in five healthy goats and five goats infected with the caprine arthritis encephalitis virus (CAEV) were examined using immunofluorescence and flow cytometry. A panel of monoclonal antibodies that identified a monocytegranulocyte marker (GMI); the CD4, CD8, IgM, MHC Class I, MHC Class II and T19 antigens, and the gamma delta (gamma delta) T cell receptor was used. We observed a significant (P = 0.016) reduction in the proportion of monocytes in the peripheral blood of infected (5.98%) compared with healthy control goats (9.92%). There was also a decrease in the proportion of CD4+ T lymphocytes that approached significance (P = 0.076) accompanied by a slight increase in the proportion of CD8+ T lymphocytes, in infected compared with uninfected animals. Consequently, three of the five infected animals had lower CD4:CD8 ratios than any of the healthy animals and two of these three ratios were inverted. Approximately 14% of T cells in the peripheral blood of healthy goats was identified as gamma delta T cells and all expressed the T19 antigen. A significantly elevated level of gamma delta T cells (P = 0.030) and an elevated level of T19 cells were observed in infected, compared with healthy animals. The proportion of leukocytes expressing surface IgM (B cells) was also elevated, although not significantly, in CAEV-infected compared to healthy controls. The changes in peripheral blood leukocyte subsets in infected goats suggest that immune responses to the infection are probably altered in these animals with eventual progression to severe disease and death.
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Affiliation(s)
- P E Jolly
- Department of International Health, University of Alabama at Birmingham 32594, USA
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Gangopadhyay A, Bajenova O, Kelly TM, Thomas P. Carcinoembryonic antigen induces cytokine expression in Kuppfer cells: implications for hepatic metastasis from colorectal cancer. Cancer Res 1996; 56:4805-10. [PMID: 8841002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The mechanism by which carcinoembryonic antigen (CEA) causes enhancement of hepatic metastasis from colorectal cancer is not defined. We hypothesize that binding of CEA to an 80-kDa Kupffer cell receptor by the peptide sequence Pro-Glu-Leu-Pro-Lys (PELPK) induces cytokine production in the hepatic microenvironment, which then impacts on the formation of hepatic metastasis from colorectal cancer. We have, therefore, isolated Kupffer cells and treated them in vitro with CEA, its gene family member nonspecific cross-reacting antigen, PELPK-albumin conjugate, and lipopolysaccharide as a positive control. Spent media was examined for the content of cytokines interleukin (IL) 1alpha, IL-1beta, IL-6, and tumor necrosis factor alpha using the ELISA. Simultaneously, mRNA was extracted from the same cells and amplified using reverse transcription-PCR to evaluate the induction of specific cytokine transcripts. As expected, lipopolysaccharide stimulated cytokine production. CEA, nonspecific cross-reacting antigen, and PELPK-albumin induced secretion of all of the cytokines tested; the response was higher in general with PELPK-albumin. The levels of cytokine mRNA showed a similar profile. These responses were not seen when a similar but irrelevant peptide conjugate PELGK-albumin was used. These results demonstrate that binding of the peptide PELPK to the 80-kDa receptor results in the release of a series of cytokines that have the potential to activate hepatic sinusoidal endothelium. This may explain CEA-induced enhancement of experimental hepatic metastasis.
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Affiliation(s)
- A Gangopadhyay
- Laboratory of Cancer Biology, Department of Surgery, Deaconess Hospital and Harvard Medical School, Boston, Massachusetts 02215, USA
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34
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Abstract
Carcinoembryonic antigen (CEA) binds to an 80-kDa cell surface receptor on Kupffer cells via the peptide sequence PELPK (residues 108-112) located at the hinge region between the N and Al immunoglobulin-like domains. This study is aimed at analyzing the specificity of the peptide binding, determining biodistribution of 80-kDa receptor, and processing of CEA by this receptor. We synthesized a number of bovine serum albumin (BSA) derivatives carrying PELPK and related sequences. A series of peptides (YPELPK, YPDLPK, YPDLPR, and YPELGK) were conjugated to bovine serum albumin using N-hydroxysuccinimidyl-4-azidobenzoate. When 125I peptide conjugates, CEA, and BSA were injected intravenously into rats CEA and the PELPK-albumin conjugate were cleared rapidly. The other peptide conjugates and BSA cleared at a much slower rate. Activity of 125I-labeled CEA and PELPK-albumin conjugate per gram of tissue was highest for the liver and spleen. Clearance of 125I-CEA was inhibited by the presence of higher concentrations of the PELPK-albumin conjugate. With isolated rat Kupffer cells, only CEA and the PELPK-albumin conjugate were bound and internalized in vitro and CEA binding was inhibited by higher concentrations of the PELPK-albumin conjugate. Similarly, binding of the PELPK-albumin conjugate was inhibited by the presence of unlabeled CEA. Use of a heterobifunctional cross linking agent demonstrated reaction of the PELPK-albumin with an 80-kDa protein on the Kupffer cell surface by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). This semisynthetic ligand (PELPK-albumin) allows us to examine the function of the 80-kDa receptor without interference due to other properties of CEA including its ability to bind lectins and to cause homotypic aggregation of cells. The consequences of CEA binding to the 80-kDa receptor may have implications in the development of hepatic metastasis from colorectal cancer.
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Affiliation(s)
- A Gangopadhyay
- Laboratory of Cancer Biology, Department of Surgery, Deaconess Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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Abstract
We evaluated the influence of changes in charge on the biodistribution of 111In-labeled purified rabbit antihuman serum albumin (R-HSA) IgG conjugated to diethylenetriaminepentaacetic dianhydride (DTPA). Optimization of isoelectric point (pI) may influence the biodistribution profile, especially retention in vital organs, which ultimately affects radioimmunoimaging. Experiments were designed to modify the pI of R-HSA by conjugating various molar ratios of DTPA (DTPA:R-HSA ratios 5:1 to 100:1). The pI of the conjugates was determined by isoelectricfocusing (IEF). 111In-labeled DTPA:R-HSA with known pI range was injected intraperitoneally into BALB/c mice to evaluate biodistribution. There was a proportional relationship between the molar ratio of DTPA to R-HSA IgG and the number of DTPA substituted. Molar ratios of 5, 10, 20, 50 and 100 gave, on average, 2.0, 3.6, 5.1, 9.5 and 16.0 DTPA per R-HSA IgG, respectively. An anodal shift in the pI of 111In-labeled R-HSA IgG was noted with increased number of DTPA conjugation. Biodistribution studies at both 4 and 24 h showed sequential increase in the liver activity with increasing number of DTPA per antibody, whereas colon and small intestine showed a decrease in the activity at 4 h. The organ-specific increase (e.g., liver) or decrease (e.g., colon and small intestine) in the activity may depend on a critical balance of charge of a particular organ and its interaction with the amount of negative charge carried by the antibody conjugate. The results suggest that pI optimized 111In-labeled antibody could be used to increase or decrease colon and hepatic retention for more efficient radioimmunoimaging of colon tumors and their hepatic metastasis.
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Affiliation(s)
- A Gangopadhyay
- Department of Surgery, Deaconess Hospital, Harvard Medical School, Boston, MA 02115, USA
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Gangopadhyay A, Lazure DA, Kelly TM, Thomas P. Purification and analysis of an 80-kDa carcinoembryonic antigen-binding protein from Kupffer cells. Arch Biochem Biophys 1996; 328:151-7. [PMID: 8638924 DOI: 10.1006/abbi.1996.0155] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The receptor-mediated interaction of Kupffer cells with carcinoembryonic antigen (CEA) has led to the identification of an 80-kDa CEA-binding Kupffer cell protein. This study is aimed at the isolation and analyses of this protein from rat Kupffer cells. The binding protein was purified using a combination of gel filtration, preparative polyacrylamide gel electrophoresis (PPAGE), and affinity chromatography using a CEA-Sepharose column. Fractions obtained from the gel filtration produced two major and few minor peaks with CEA-binding activity. Maximum reactivity was detected in the first major peak. The first major peak protein was partially precipitated following fractionation with 30% loss of activity in the precipitate. Fractions with CEA-binding activity were pooled and separated on the basis of molecular weight (MW) in PPAGE. The fractions between MW 70 and 90 kDa were pooled and affinity purified using CEA-Sepharose affinity chromatography. The purity of the 80-kDa protein was demonstrated by a single protein band on SDS-polyacrylamide gel. The protein was further identified by an anti-80-kDa binding protein antibody in Western blot analysis. The pI of the 80-kDa protein is 4.95. Amino acid analysis demonstrated no histidine; higher percentages of glutamine (13.3%), leucine (11.2%), asparagine and alanine (10.4%), and lysine (9.2%) were observed. Protein microsequencing revealed two unique sequences, one with 16 amino acids and the other with 11 amino acids. The 16-amino-acid sequence has less than 50% homology with a large sample of unrelated proteins, whereas the sequence containing 11 amino acids has 60-70% homology with the alpha chain of collagen from a variety of species but no significant homology with other known proteins, suggesting the presence of collagen-like domains in the 80-kDa receptor.
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Affiliation(s)
- A Gangopadhyay
- Laboratory of Cancer Biology, Deaconess Hospital and Harvard Medical School, Boston, Massachussetts 02115, USA
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Wang J, Brunner CJ, Gangopadhyay A, Bird AC, Wolfe LG. Detection of tumor-associated antigens in sera of canine cancer patients by monoclonal antibodies generated against canine mammary carcinoma cells. Vet Immunol Immunopathol 1995; 48:193-207. [PMID: 8578680 DOI: 10.1016/0165-2427(95)05436-a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Two murine monoclonal antibodies (MAbs), 1A10 and SB2, generated against a canine mammary carcinoma cell line, were used in a competitive enzyme-linked immunosorbent assay (ELISA) to measure tumor-associated antigens (TAAs) in canine serum samples. Sera were tested from disease-free dogs and from dogs diagnosed with mammary carcinoma, non-mammary carcinoma, sarcoma, benign mammary tumor, benign non-mammary tumor, or non-neoplastic disease. Serum antigen concentrations measured by ELISA were expressed as inhibitory units (IU). The upper limit of normal, defined as the mean plus 2 SD of the TAA concentration in disease-free dogs, was 20 IU with antibody 1A10 and 22 IU with antibody SB2. Compared with disease-free dogs, the frequency of TAA-positive sera was significantly greater (P < 0.05) among dogs with mammary or non-mammary carcinoma when tested with MAbs 1A10 or SB2, and also with sarcoma when tested with MAb SB2. Testing a serum sample with both antibodies rather than just one increased the sensitivity of the competitive ELISA for TAA detection. The presence of TAA in serum might serve as a useful marker for certain types of carcinomas or sarcomas in canine cancer patients.
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Affiliation(s)
- J Wang
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, AL 36849-5519, USA
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Gangopadhyay A, Saravis CA, van den Abbeele AD, Kassis AI. pI-dependent isolation of antibody isoforms by semipreparative isoelectric focusing. Q J Nucl Med 1995; 39:129-33. [PMID: 8574807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A procedure based on isoelectric point (pI) was developed to separate immunoreactive antibody isoforms. A polyclonal IgG, rabbit anti-human serum albumin (R-HSA), was subjected to free-flow isoelectrophoresis using a semipreparative isoelectric focusing apparatus that fractionates proteins by pI. Twenty fractions were collected and their pH, protein content, and immunoreactivity determined. The development of a pH gradient and separation of proteins took place within 3 hours with about 93% protein recovery. The protein concentration of the individual fractions varied. Isoelectric focusing of fractions in agarose slab gels confirmed the clear separation of antibody isoforms. Enzyme-linked immunosorbent assay demonstrated significantly higher immunoreactivity (P < or = 0.03) of the majority of the antibody isoform fractions compared with native R-HSA IgG. The procedure is capable of isolating immunoreactive antibody isoform fractions from immunologically irrelevant and low-affinity antibodies.
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Affiliation(s)
- A Gangopadhyay
- Department of Radiology (Division of Nuclear Medicine), Harvard Medical School, Boston, MA 02115, USA
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Thomas P, Gangopadhyay A, Steele G, Andrews C, Nakazato H, Oikawa S, Jessup JM. The effect of transfection of the CEA gene on the metastatic behavior of the human colorectal cancer cell line MIP-101. Cancer Lett 1995; 92:59-66. [PMID: 7757961 DOI: 10.1016/0304-3835(95)03764-n] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Carcinoembryonic antigen (CEA) has been shown to increase the metastatic potential of some human colorectal cancer cell lines. To investigate further the mechanisms involved we have produced three clones (6, 8 and 17) from the poorly differentiated human colorectal cancer cell line MIP-101 that have been transfected with the full length cDNA encoding for human carcinoembryonic antigen (CEA). They produce CEA with a mol. wt. of 180000 by Western blotting and secrete it into the culture medium. Clone 6 is a high CEA producer, clones 8 and 17 are intermediate producers. The doubling time for clone 8 was similar to that of the parent cell line while clones 6 and 17 had doubling times nearly twice that of the parent cells. These clones are tumorigenic when injected subcutaneously in nude mice are positive for CEA by immunoperoxidase staining and the mice have elevated blood levels of CEA. Clone 6 formed large aggregates in culture while clone 17 formed smaller aggregates. Clone 8 behaved like the parent cell line with rare cell/cell contact. Clones 6 and 17 also adhered to CEA coated plastic while clone 8, a neo-transfected control and the parent cell line did not. A significant increase in the incidence of hepatic tumors was observed with clone 6 (P < 0.01) and clone 17 (P < 0.02) following intrasplenic injection into nude mice. Immunohistopathology of the hepatic tumors showed strong CEA staining from clones 6 and 17 with weak staining from clone 8. The parent cell line was negative for CEA as were the neo-transfected controls. Of the neo controls none of 10 had liver colonies. Mice injected with clone 6 which developed liver metastasis had the highest plasma levels of CEA (37.3 +/- 8.8 ng/ml). We observed strong CEA staining in Kupffer cells in the normal liver adjacent to the CEA producing tumors. This study provides further evidence for the involvement of CEA in the metastatic process.
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Affiliation(s)
- P Thomas
- Department of Surgery, Deaconess Hospital, Harvard Medical School, Boston, MA 02115, USA
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Gangopadhyay A, Saravis CA, Kassis AI. Semipreparative isoelectrophoresis of DTPA-conjugated antibody leads to isolation of antibody isoforms with different immunoreactivities. J Nucl Biol Med (1991) 1994; 38:61-7. [PMID: 8075178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Diethylenetriaminepentaacetic acid (DTPA)-conjugated purified rabbit anti-human serum albumin antibody was subjected to free-flow, semipreparative isoelectrophoresis using an apparatus that fractionates protein molecules based on isoelectric point (pI). The results indicate that (1) the apparatus was capable of developing linear pH gradients and separating proteins, (2) > or = 86% of the protein was recovered following fractionation, and (3) the protein concentration of the individual fractions varied. Focusing the fractions on an isoelectric slab gel revealed that the pIs of the isoforms were modified. The isoforms were radiolabeled with indium-111, their DTPA to antibody molar ratios determined, and their immunoreactivities evaluated by a solid-phase radioimmunoassay. The results demonstrate that (1) the molar ratio of DTPA to antibody varied among the fractions, and (2) the immunoreactivity of the majority of fractions was higher than that of unfractionated DTPA-antibody conjugate. Semipreparative isoelectric focusing may therefore improve the potential of radioimmunoconjugates in the radio-diagnosis and therapy of disease.
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Affiliation(s)
- A Gangopadhyay
- Department of Radiology (Division of Nuclear Medicine) Harvard Medical School, Boston, Massachusetts 02115
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Gangopadhyay A, Jahanmir S, Hegemann B. Paper III (i) Reduction in friction coefficient in sliding ceramic surfaces by in-situ formation of solid lubricant coatings. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/s0167-8922(08)70242-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Gangopadhyay A, Wolfe LG. Conserved antigen expression in epithelial tumors recognized by monoclonal antibody 4A9 generated against canine mammary carcinoma cells. Hybridoma (Larchmt) 1989; 8:175-86. [PMID: 2714814 DOI: 10.1089/hyb.1989.8.175] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Hybridoma-derived murine monoclonal antibodies (MoAbs) were generated by fusing P3X63-Ag8.653 myeloma cells with splenic cells from BALB/c mouse which had been immunized with viable canine mammary adenocarcinoma cells, CMT-2. Fifteen MoAbs were shown to react with immunizing cells in indirect immunofluorescence (IFA) and enzyme-linked immunosorbent (ELISA) assays. The reactivity of one IgM MoAb, designated 4A9, was evaluated. The antigen recognized by 4A9 on CMT-2 cells appeared to be localized both in cell membrane and cytoplasm against fixed and unfixed preparations by IFA. The 4A9 MoAb was found to bind with four of five canine mammary carcinoma cell lines while no binding was detected with normal fibroblastic cell lines. In vivo tissue distribution of 4A9 antigen was evaluated by indirect immunoperoxidase (IP) assay against formalin-fixed, paraffin-embedded sections of normal and neoplastic tissues. 4A9 MoAb reacted strongly to moderately with 75% of mammary carcinomas, moderately to weakly with 57% of benign mammary tumors, and strongly with squamous cell and perianal gland carcinomas (100%), interstitial cell tumors (100%), transitional cell carcinomas (43%), lung adenocarcinomas (40%), colon carcinomas (33%), and pancreatic adenocarcinomas (20%). Moderate to weak staining was detected with granulosa cell tumors (25%) and apocrine gland adenocarcinomas (50%). Strong reactivity with perianal gland carcinomas contrasted to no reactivity with perianal gland adenomas. No immunostaining was detected with a large variety and number of normal adult and fetal tissues tested; negligible and very restricted staining was observed in a few adult and fetal tissues. Normal mammary gland was negative. Since the antigen is expressed on the cell surface and in the cytoplasm of most mammary carcinoma cells and a variety of other epithelial tumor cells, the 4A9 antibody may have potential application in diagnosis and management of canine mammary cancer and a variety of other epithelial tumors.
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Gangopadhyay A, Chatterjee SK, Bhattacharya M, Barlow JJ. Characterization of the antigen recognized by monoclonal antibody 1D3. Cancer Biochem Biophys 1988; 10:107-15. [PMID: 3252956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Human ovarian mucinous cystadenocarcinoma-associated antigen recognized by murine monoclonal antibody 1D3 (Bhattacharya et al., 1982) was characterized. Gel filtration and sodium dodecylsulfate polyacrylamide gel electrophoresis, followed by Western-blot analysis showed that 1D3 is a high molecular weight glycoprotein. Isoelectric focusing of 1D3 antigen showed 2 overlapping antigenic components with PI 2.5 and 2.6. 1D3 antigen was extremely stable (10 min at 100 degrees C) to heating. The antigenic activity was slightly stimulated by treatment with galactosidases, but neuraminidase treatment enhanced the antigenic activity about 3-fold. Antigen activity was completely stable to periodate oxidation. Pronase and trypsin treatment completely destroyed the antigenic activity. Properties of 1D3 antigen suggest that this is a high molecular weight (approximately 5-20 x 10(6) Dalton), sialomucin. Monoclonal antibody 1D3 recognizes only the protein part of this molecule.
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Affiliation(s)
- A Gangopadhyay
- Department of Gynecologic Oncology, Roswell Park Memorial Institute, Buffalo, New York 14263
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Moore J, Perez R, Gangopadhyay A, Eggert J. Factors affecting wear in tumbling mills: Influence of composition and microstructure. ACTA ACUST UNITED AC 1988. [DOI: 10.1016/0301-7516(88)90071-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Gangopadhyay A, Barlow JJ, Petrelli NJ, Tsukada Y, Bhattacharya-Chatterjee M. Expression of a high molecular weight mucin-type glycoprotein in human colon cancer as defined by monoclonal antibody 1D3. Hybridoma (Larchmt) 1988; 7:141-54. [PMID: 3286482 DOI: 10.1089/hyb.1988.7.141] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Murine monoclonal antibody 1D3 recognizes a high molecular weight acidic mucin restricted to the epithelium of normal colonic mucosa and goblet cells. Of 72 colonic carcinoma specimens examined, 29 were found to have detectable level of 1D3 antigen by an indirect immunoperoxidase staining assay on fixed, paraffin-embedded tissue sections. In some specimens a focal staining pattern was observed, while in others 50-90% of tumor cells were stained. Of 28 cases having adjacent normal mucosa, all 28 showed intense staining reaction in the normal mucosa and goblet cells despite the fact that 18 of the tumors were unstained. One of 1 colonic diverticulosis, 2 of 2 ulcerative colitis, 3 of 3 villo-glandular polyps, 19 of 20 adenomatous polyps and 17 of 19 hyperplastic polyps were also stained heavily for the 1D3 antigen. Colonic carcinomas displayed a range of staining patterns and a great degree of antigenic heterogeneity. Well-differentiated tumors characterized by typical goblet cells were almost always positive (10 of 12). As cellular structure became disorganized, as in moderately-differentiated tumors, about 33% of the tumors (17 of 51) stained for 1D3 antigen. As the tumor became more invasive with further disorientation of cellular features, as in poorly differentiated tumors, very few specimens (2 of 9) were positive. It was apparent that with the progression of de-differentiation there was a gradual loss of 1D3 antigen in human colonic tumors.
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Affiliation(s)
- A Gangopadhyay
- Department of Gynecologic Oncology, Roswell Park Memorial Institute, Buffalo, NY 14263
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Bhattacharya M, Chatterjee SK, Gangopadhyay A, Barlow JJ. Production of murine monoclonal antibodies against cell-surface antigens of human ovarian carcinoma. J Surg Oncol 1985; 30:209-14. [PMID: 2417057 DOI: 10.1002/jso.2930300405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Splenic lymphocytes of BALB/c mice immunized with human ovarian carcinoma cells were fused with the mouse myeloma cell line, NS-1 in the presence of polyethylene glycol, MW 1500. The hybrid cultures were screened by a viable cell-binding radioimmunoassay (RIA) for the production of relevant antibodies. Hybrids that produced antibodies that bound to the surface of the immunizing cell line and other ovarian carcinoma cell lines, but not to human fibroblast cell lines or erythrocytes and leucocytes isolated from peripheral blood, were cloned twice by the limiting dilution method. Two such clones designated 8C3, of the IgG2a isotype, and 10D6, of the IgG1 isotype, were checked for specificity by a solid-phase membrane RIA. The monoclonal antibodies (MoAbs) recognized an antigenic determinant present on different human adenocarcinomas such as ovary, breast, endometrium, colon, and stomach. The normal counterpart tissues of these histiotypes showed negligible binding to the MoAbs. The relative specificity of these MoAbs encourage further studies towards their characterization and evaluation as possible diagnostic and therapeutic agents in human cancer.
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Gangopadhyay A, Bhattacharya M, Chatterjee SK, Barlow JJ, Tsukada Y. Immunoperoxidase localization of a high-molecular-weight mucin recognized by monoclonal antibody 1D3. Cancer Res 1985; 45:1744-52. [PMID: 3884144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The distribution of an antigen recognized by murine monoclonal antibody 1D3 (Bhattacharya, M., Chatterjee, S.K., Barlow, J. J., and Fuji, H. Cancer Res., 42: 1650-1654, 1982) was investigated in various types of human malignant and normal adult tissues by indirect immunoperoxidase assay in fixed paraffin-embedded sections. One hundred percent of ovarian mucinous cystadenocarcinomas expressed high levels of the antigen with intense staining of 80 to 100% of the tumoral area, thus confirming our previous finding with radioimmunoassay and absorption analyses. About 51% of colonic carcinomas, 33% of gastric carcinomas, and 22% of pancreatic carcinomas were also positive for this high-molecular-weight mucoprotein antigen. All other ovarian and nonovarian carcinomas tested including carcinoma of lung, breast, endometrium, cervix, and prostate were not stained by 1D3. In addition, sarcomas, melanomas, and lymphomas also did not express any detectable level of the antigen. When surveyed against various normal adult tissues, 1D3 had reactivity limited to the colon. Normal colon, however, exhibited reduced staining intensities compared to tumors or to the apparently normal colon adjacent to tumors. The antigen thus appears to be a colorectal tissue-specific antigen showing increased levels in ovarian mucinous cystadenocarcinomas and in some gastrointestinal tumors. 1D3 antigen is a potential tumor marker for mucinous ovarian and colonic tumors.
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Bhattacharya M, Chatterjee SK, Gangopadhyay A, Barlow JJ. Production and characterization of monoclonal antibody to a 60-kD glycoprotein in ovarian carcinoma. Hybridoma (Larchmt) 1985; 4:153-62. [PMID: 3891588 DOI: 10.1089/hyb.1985.4.153] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Monoclonal IgG1 antibodies 2C8 and 2F7, derived by immunization of mice with a glycoprotein-enriched fraction of human ovarian adenocarcinoma, recognized a 60 kD glycoprotein in the ovarian tumor but not in normal ovary. Survey of other normal adult tissues by an indirect solid-phase radioimmunoassay (RIA) revealed the presence of the antigen in trace amounts in various normal organs such as small intestine, liver colon and urinary bladder, except in lung where its concentration was as high as in tumors. Among fetal tissues tested, intestine and placenta had the highest activities. By RIA, about 50% of ovarian and colonic tumors had elevated levels of the antigen. All ovarian cyst fluids, both benign as well as malignant, also contained a high level of the antigen. Immunodepletion studies indicated that the antigen was distinct from carcinoembryonic antigen and the ovarian cancer antigens described in our laboratory with other monoclonal antibodies. The antigen bound to Con A-Sepharose and was eluted with 2% alpha-D-mannoside, was soluble in 0.6 M perchloric acid and stable at 100 degrees C for 30 min. The antigenic activity in isolated plasma membrane enriched fractions of ovarian adenocarcinomas was sensitive to trypsin, chymotrypsin or protease treatment but unaffected by neuraminidase, beta-galactosidase, periodate or methanol treatment. By immunoperoxidase staining, the antigen was localized in a variety of human tumors showing widespread distribution.
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Abstract
The treatment of Amoeba indica with ethylmethanesulphonate (EMS) at early S, late S and late G2 phases of the cell cycle leads to the production of mini amoeba cells in the G2 period. Among them, only a few of the mini cells that originated from EMS treatment at early S phase have been found to be viable and to give rise to stable clones. These mini amoebae show stable and altered characteristic features in cell size, structure, membrane properties, cell-cycle timing and the patterns of macromolecular syntheses as compared to the parental cells. It is suggested that the mini amoeba cell is a size mutant that has a cell-cycle-phase-specific origin. The finding is discussed in relation to preferential mutagenic action involving the functional state of DNA leading to the production of viable mutant amoebae.
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