Unconventional immunotherapy with an unconventional target

2020 ◽  
pp. 1-6
Author(s):  
Mark C. Glassy

Pritumumab, a natural human IgG1 kappa antibody was obtained from a regional draining lymph node of a patient with cervical carcinoma through traditional hybridoma technology. Specificity analysis of the target antigen, an altered form of vimentin called, ecto-domain vimentin (EDV), shows it to be limited to cell surface expression on cancer cells. Clinically, 249 brain cancer patients were treated with a low dose pritumumab regimen, either at 1 mg once a week or 1 mg twice a week, and of those evaluated overall response rates of between 25–30% were seen with several complete and partial responses. A clinical trial assessing higher doses of pritumumab as a therapeutic for brain cancer is expected to begin this year. Overall, these data together suggest pritumumab is suitable for further development as an anti-tumor therapeutic.

2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 71-71
Author(s):  
Ivan Babic ◽  
Rajesh Mukthavaram ◽  
Pengfei Jiang ◽  
Natsuko Nomura ◽  
Eric Glassy ◽  
...  

71 Background: Pritumumab, a natural huma IgG1 kappa antibody was obtained from a regional draining lymph node of a patient with cervical carcinoma through traditional hybridoma technology. Methods: Both cell lines and tissues were processed and analyzed for FACS analysis, Western blots, and immunohistochemistry. Results: Specificity analysis of the target antigen, an altered form of vimentin (ecto-domain vimentin (EDV)) shows it to be limited to cell surface expression on cancer cells. Clinically, 249 Japanese brain cancer patients were treated with a low dose pritumumab regimen, either at 1mg once a week or 1mg twice a week, and overall response rates of between 25-30% were seen with several complete and partial responses. A recombinant version of the mAb was made using the GPEx system in CHO cells. In a series of comparable studies the CHO mAb was compared with the original hybridoma. Binding specificity with both flow cytometry and immunohistochemical (IHC) analysis, Western blot analysis, and Antibody-Dependent Cell-Mediated Cytotoxicity (ADCC) activity confirms the comparability of the two versions. IHC analysis suggests restricted binding to tumor cells and not normal cells and tissues. Further studies include establishing a xenograft model with both SCID and athymic nude mice in which pritumumab was effective in preventing tumor growth in nude mice but not in SCID mice. Analysis of a blood brain barrier model suggests pritumumab shows minimal distribution in normal brain tissues and significant binding in tumor areas of brain tissues indicating the mAb crosses the tumor brain barrier. Conclusions: Overall, these data together suggest pritumumab is suitable for development as an anti-tumor therapeutic.


1999 ◽  
Vol 81 (04) ◽  
pp. 594-560 ◽  
Author(s):  
Florence Ganné ◽  
Marc Vasse ◽  
Jean-Louis Beaudeu ◽  
Jacqueline Peynet ◽  
Arnaud François ◽  
...  

SummaryMonocyte-derived foam cells figure prominently in rupture-prone regions of atherosclerotic plaque. As urokinase/urokinase-receptor (u-PA/u-PAR) is the trigger of a proteolytic cascade responsible for ECM degradation, we have examined the effect of atherogenic lipoproteins on monocyte surface expression of u-PAR and u-PA. Peripheral blood monocytes, isolated from 10 healthy volunteers, were incubated with 10 to 200 µg/ml of native or oxidised (ox-) atherogenous lipoproteins for 18 h and cell surface expression of u-PA and u-PAR was analysed by flow cytometry. Both LDL and Lp(a) induced a dose-dependent increase in u-PA (1.6-fold increase with 200 μg/ml of ox-LDL) and u-PAR [1.7-fold increase with 200 μg/ml of ox-Lp(a)]. There is a great variability of the response among the donors, some of them remaining non-responders (absence of increase of u-PA or u-PAR) even at 200 μg/ml of lipoproteins. In positive responders, enhanced u-PA/u-PAR is associated with a significant increase of plasmin generation (1.9-fold increase with 200 μg/ml of ox-LDL), as determined by an amidolytic assay. Furthermore, monocyte adhesion to vitronectin and fibrinogen was significantly enhanced by the lipoproteins [respectively 2-fold and 1.7-fold increase with 200 μg/ml of ox-Lp(a)], due to the increase of u-PAR and ICAM-1, which are receptors for vitronectin and fibrinogen. These data suggest that atherogenous lipoproteins could contribute to the development of atheromatous plaque by increasing monocyte adhesion and trigger plaque weakening by inducing ECM degradation.


2020 ◽  
Author(s):  
Florent Colomb ◽  
Leila B. Giron ◽  
Leticia Kuri Cervantes ◽  
Tongcui Ma ◽  
Samson Adeniji ◽  
...  

Author(s):  
Mona Aslani ◽  
Arman Ahmadzadeh ◽  
Zahra Aghazadeh ◽  
Majid Zaki-Dizaji ◽  
Laleh Sharifi ◽  
...  

Background: : Based on the encouraging results of phase III clinical trial of β-D-mannuronic acid (M2000) (as a new anti-inflammatory drug) in patients with RA, in this study, we aimed to evaluate the effects of this drug on the expression of chemokines and their receptors in PBMCs of RA patients. Methods:: PBMCs of RA patients and healthy controls were separated and the patients' cells were treated with low, moderate and high doses (5, 25 and 50 μg/mL) of M2000 and optimum dose (1 μg/mL) of diclofenac, as a control in RPMI-1640 medium. Real-time PCR was used for evaluating the mRNA expression of CXCR3, CXCR4, CCR2, CCR5 and CCL2/MCP-1. Cell surface expression of CCR2 was investigated using flow cytometry. Results:: CCR5 mRNA expression reduced significantly, after treatment of the patients' cells with all three doses of M2000 and optimum dose of diclofenac. CXCR3 mRNA expression down-regulated significantly followed by treatment of these cells with moderate and high doses of M2000 and optimum dose of diclofenac. CXCR4 mRNA expression declined significantly after treatment of these cells with moderate and high doses of M2000. CCL2 mRNA expression significantly reduced only followed by treatment of these cells with high dose of M2000, whereas, mRNA and cell surface expressions of CCR2 diminished significantly followed by treatment of these cells with high dose of M2000 and optimum dose of diclofenac. Conclusion:: According to our results, M2000 through the down-regulation of chemokines and their receptors may restrict the infiltration of immune cells into the synovium.


1990 ◽  
Vol 64 (10) ◽  
pp. 4776-4783 ◽  
Author(s):  
M E Andrew ◽  
D B Boyle ◽  
P L Whitfeld ◽  
L J Lockett ◽  
I D Anthony ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document