Effects of a Hybrid Recombinant Human Alpha Interferon (A/D) on in vitro Cytotoxicity and in vivo Localization of Monoclonal Antibody L6-Cytosine Deaminase Conjugate in a Colon Cancer Model

1998 ◽  
Vol 13 (1) ◽  
pp. 33-42 ◽  
Author(s):  
Kevin P. O'Boyle ◽  
Peter D. Senter ◽  
Kuldeep Bhargava ◽  
Sam Chun ◽  
Gillian Anthony ◽  
...  
2020 ◽  
Vol 2 (1) ◽  
pp. FDD28 ◽  
Author(s):  
Oleg Babii ◽  
Sergii Afonin ◽  
Tim Schober ◽  
Liudmyla V Garmanchuk ◽  
Liudmyla I Ostapchenko ◽  
...  

Aim: To verify whether photocontrol of biological activity could augment safety of a chemotherapeutic agent. Materials & methods: LD50 values for gramicidin S and photoisomeric forms of its photoswitchable diarylethene-containing analogs were determined using mice. The results were compared with data obtained from cell viability measurements taken for the same compounds. Absorption, Distribution, Metabolism, and Elimination (ADME) tests using a murine cancer model were conducted to get insight into the underlying reasons for the observed in vivo toxicity. Results: While in vitro cytotoxicity values of the photoisomers differed substantially, the differences in the observed LD50 values were less pronounced due to unfavorable pharmacokinetic parameters. Conclusion: Despite unfavorable pharmacokinetic properties as in the representative case studied here, there is an overall advantage to be gained in the safety profile of a chemotherapeutic agent via photocontrol. Nevertheless, optimization of the pharmacokinetic parameters of photoisomers is an important issue to be addressed during the development of photopharmacological drugs.


Author(s):  
Albert A Baskar ◽  
Savarimuthu Ignacimuthu ◽  
Gabriel M Paulraj ◽  
Khalid S Al Numair

2011 ◽  
Vol 29 (4_suppl) ◽  
pp. 432-432 ◽  
Author(s):  
N. Sawada ◽  
E. Taguchi ◽  
M. Takahashi

432 Background: KRN330 is a novel recombinant human IgG1 monoclonal antibody (mAb) targeting A33 surface differentiation antigen that is uniformly expressed on the surface of 95% of colorectal cancer (CRC) cells. In this study, we characterized the activity of KRN330 for its in vitro properties, as well as for its in vivo antitumor activity. Methods: A kinetic analysis of the interaction between KRN330 and recombinant human A33 was conducted using a Biacore 3000. Western blot analysis was conducted using A33 expressing COLO205 lysates under reducing and non-reducing conditions. Binding of KRN330 to human colorectal cancer tissues were investigated using FITC-labeled KRN330. We also developed more conventional staining methods of A33 and investigated A33 expression using human colon cancer tissue microarray (TMA). ADCC and CDC activities of KRN330 were assessed using a standard 51Cr release assay. A33 expression levels of 14 CRC cell lines were analyzed using flow cytometer. In vivo antitumor activities of KRN330 alone or in combination with chemotherapeutic agents against subcutaneous or intraperiotoneal human CRC (COLO205 and LS174T) models were investigated using mice and rats xenograft model. Results: A kinetic analysis revealed that KRN330 showed a high binding affinity to A33. Western blot analysis also showed that antibody recognized not any protein under reducing condition, but non-reducing condition. A33 staining of TMA with 204 different samples revealed the majority of tumor expressed A33. KRN330 exhibited ADCC activity against A33 expressing human colorectal cancer cell lines which include both K-ras wild and mutated types. KRN330 showed dose-dependent antitumor activities in vivo. KRN330 also significantly prolonged survival of human colon tumor bearing mice. In addition, combination treatment of KRN330 with irinotecan showed increased antitumor activitiy and prolongation of survival, compared to either irinotecan or KRN330 alone. Conclusions: These results suggest that KRN330 is a promising candidate of novel therapy for CRC. The phase I/II study of KRN330 plus irinotecan in patients with second line metastatic CRC is ongoing. [Table: see text]


1988 ◽  
Vol 60 (02) ◽  
pp. 298-304 ◽  
Author(s):  
C A Mitchell ◽  
S M Kelemen ◽  
H H Salem

SummaryProtein S (PS) is a vitamin K-dependent anticoagulant that acts as a cofactor to activated protein C (APC). To date PS has not been shown to possess anticoagulant activity in the absence of APC.In this study, we have developed monoclonal antibody to protein S and used to purify the protein to homogeneity from plasma. Affinity purified protein S (PSM), although identical to the conventionally purified protein as judged by SDS-PAGE, had significant anticoagulant activity in the absence of APC when measured in a factor Xa recalcification time. Using SDS-PAGE we have demonstrated that prothrombin cleavage by factor X awas inhibited in the presence of PSM. Kinetic analysis of the reaction revealed that PSM competitively inhibited factor X amediated cleavage of prothrombin. PS preincubated with the monoclonal antibody, acquired similar anticoagulant properties. These results suggest that the interaction of the monoclonal antibody with PS results in an alteration in the protein exposing sites that mediate the observed anticoagulant effect. Support that the protein was altered was derived from the observation that PSM was eight fold more sensitive to cleavage by thrombin and human neutrophil elastase than conventionally purified protein S.These observations suggest that PS can be modified in vitro to a protein with APC-independent anticoagulant activity and raise the possibility that a similar alteration could occur in vivo through the binding protein S to a cellular or plasma protein.


2018 ◽  
Vol 15 (4) ◽  
pp. 564-575 ◽  
Author(s):  
Arehalli S. Manjappa ◽  
Popat S. Kumbhar ◽  
Prajakta S. Khopade ◽  
Ajit B. Patil ◽  
John I. Disouza

2020 ◽  
Vol 17 ◽  
Author(s):  
Akhlesh Kumar Jain ◽  
Hitesh Sahu ◽  
Keerti Mishra ◽  
Suresh Thareja

Aim: To design D-Mannose conjugated 5-Fluorouracil (5-FU) loaded Jackfruit seed starch nanoparticles (JFSSNPs) for site specific delivery. Background: Liver cancer is the third leading cause of death in world and fifth most often diagnosed cancer is the major global threat to public health. Treatment of liver cancer with conventional method bears several side effects, thus to undertake these side effects as a formulation challenge, it is necessary to develop novel target specific drug delivery system for the effective and better localization of drug into the proximity of target with restricting the movement of drug in normal tissues. Objective: To optimize and characterize the developed D-Mannose conjugated 5-Fluorouracil (5-FU) loaded Jackfruit seed starch nanoparticles (JFSSNPs) for effective treatment of liver cancer. Materials and methods: 5-FU loaded JFSSNPs were prepared and optimized formulation had higher encapsulation efficiency were conjugated with D-Mannose. These formulations were characterized for size, morphology, zeta potential, X-Ray Diffraction, and Differential Scanning Calorimetry. Potential of NPs were studied using in vitro cytotoxicity assay, in vivo kinetic studies and bio-distribution studies. Result and discussion: 5-Fluorouracil loaded NPs had particle size between 336 to 802nm with drug entrapment efficiency was between 64.2 to 82.3%. In XRD analysis, 5-FU peak was diminished in the diffractogram, which could be attributed to the successful incorporation of drug in amorphous form. DSC study suggests there was no physical interaction between 5- FU and Polymer. NPs showed sustained in vitro 5-FU release up to 2 hours. In vivo, mannose conjugated NPs prolonged the plasma level of 5-FU and assist selective accumulation of 5-FU in the liver (vs other organs spleen, kidney, lungs and heart) compared to unconjugated one and plain drug. Conclusion: In vivo, bio-distribution and plasma profile studies resulted in significantly higher concentration of 5- Fluorouracil liver suggesting that these carriers are efficient, viable, and targeted carrier of 5-FU treatment of liver cancer.


2021 ◽  
Vol 129 (5) ◽  
pp. 053301
Author(s):  
Eric Freund ◽  
Lea Miebach ◽  
Ramona Clemen ◽  
Michael Schmidt ◽  
Amanda Heidecke ◽  
...  

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