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Human monoclonal antibodies targeting carbonic anhydrase IX for the molecular imaging of hypoxic regions in solid tumours.

Ahlskog JK, Schliemann C, Mårlind J, Qureshi U, Ammar A, Pedley RB, Neri D - Br. J. Cancer (2009)

Bottom Line: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo.In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting.We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Applied Biosciences, ETH Zürich, Wolfgang-Pauli-Strasse 10, Zurich CH-8093, Switzerland.

ABSTRACT

Background: Hypoxia, which is commonly observed in areas of primary tumours and of metastases, influences response to treatment. However, its characterisation has so far mainly been restricted to the ex vivo analysis of tumour sections using monoclonal antibodies specific to carbonic anhydrase IX (CA IX) or by pimonidazole staining, after the intravenous administration of this 2-nitroimidazole compound in experimental animal models.

Methods: In this study, we describe the generation of high-affinity human monoclonal antibodies (A3 and CC7) specific to human CA IX, using phage technology.

Results: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo. In one of the two animal models of colorectal cancer studied (LS174T), CA IX imaging closely matched pimonidazole staining, with a preferential staining of tumour areas characterised by little vascularity and low perfusion. In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting. We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies.

Conclusion: The new human anti-CA IX antibodies are expected to be non-immunogenic in patients with cancer and may serve as broadly applicable reagents for the non-invasive imaging of hypoxia and for pharmacodelivery applications.

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CA IX FACS histogram plots of two different human tumour cell lines. (A–C) Open curves indicate FACS histogram plots of LS174T human colorectal adenocarcinoma cells stained with SIP(A3), SIP(CC7) (both at 1 μg ml−1) or the isotype-matched control SIP(HyHEL-10) (at 9 μg ml−1), detected as described before. Solid curves represent FACS histogram plots of LS174T cells where the primary antibody was omitted for detection. (D–E) Open and solid curves indicate FACS histogram plots of SK-RC-52 human RCC cells stained as described for A–C.
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fig4: CA IX FACS histogram plots of two different human tumour cell lines. (A–C) Open curves indicate FACS histogram plots of LS174T human colorectal adenocarcinoma cells stained with SIP(A3), SIP(CC7) (both at 1 μg ml−1) or the isotype-matched control SIP(HyHEL-10) (at 9 μg ml−1), detected as described before. Solid curves represent FACS histogram plots of LS174T cells where the primary antibody was omitted for detection. (D–E) Open and solid curves indicate FACS histogram plots of SK-RC-52 human RCC cells stained as described for A–C.

Mentions: The ability of the two antibodies in SIP format to recognise the native CA IX on the surface of tumour cells was investigated by fluorescence-activated cell sorting (FACS), in comparison to a recombinant SIP antibody of irrelevant specificity (HyHEL-10; (Lavoie et al, 1992). Figure 4 shows that a partial shift in the FACS profile was observed for the colorectal cancer cell line LS174T, whereas a very marked increase of cell fluorescence was detected for the pVHL-defective human RCC cell line SK-RC-52, similar to what previously reported for the clinical-stage cG250 monoclonal antibody (Grabmaier et al, 2000).


Human monoclonal antibodies targeting carbonic anhydrase IX for the molecular imaging of hypoxic regions in solid tumours.

Ahlskog JK, Schliemann C, Mårlind J, Qureshi U, Ammar A, Pedley RB, Neri D - Br. J. Cancer (2009)

CA IX FACS histogram plots of two different human tumour cell lines. (A–C) Open curves indicate FACS histogram plots of LS174T human colorectal adenocarcinoma cells stained with SIP(A3), SIP(CC7) (both at 1 μg ml−1) or the isotype-matched control SIP(HyHEL-10) (at 9 μg ml−1), detected as described before. Solid curves represent FACS histogram plots of LS174T cells where the primary antibody was omitted for detection. (D–E) Open and solid curves indicate FACS histogram plots of SK-RC-52 human RCC cells stained as described for A–C.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2736829&req=5

fig4: CA IX FACS histogram plots of two different human tumour cell lines. (A–C) Open curves indicate FACS histogram plots of LS174T human colorectal adenocarcinoma cells stained with SIP(A3), SIP(CC7) (both at 1 μg ml−1) or the isotype-matched control SIP(HyHEL-10) (at 9 μg ml−1), detected as described before. Solid curves represent FACS histogram plots of LS174T cells where the primary antibody was omitted for detection. (D–E) Open and solid curves indicate FACS histogram plots of SK-RC-52 human RCC cells stained as described for A–C.
Mentions: The ability of the two antibodies in SIP format to recognise the native CA IX on the surface of tumour cells was investigated by fluorescence-activated cell sorting (FACS), in comparison to a recombinant SIP antibody of irrelevant specificity (HyHEL-10; (Lavoie et al, 1992). Figure 4 shows that a partial shift in the FACS profile was observed for the colorectal cancer cell line LS174T, whereas a very marked increase of cell fluorescence was detected for the pVHL-defective human RCC cell line SK-RC-52, similar to what previously reported for the clinical-stage cG250 monoclonal antibody (Grabmaier et al, 2000).

Bottom Line: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo.In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting.We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Applied Biosciences, ETH Zürich, Wolfgang-Pauli-Strasse 10, Zurich CH-8093, Switzerland.

ABSTRACT

Background: Hypoxia, which is commonly observed in areas of primary tumours and of metastases, influences response to treatment. However, its characterisation has so far mainly been restricted to the ex vivo analysis of tumour sections using monoclonal antibodies specific to carbonic anhydrase IX (CA IX) or by pimonidazole staining, after the intravenous administration of this 2-nitroimidazole compound in experimental animal models.

Methods: In this study, we describe the generation of high-affinity human monoclonal antibodies (A3 and CC7) specific to human CA IX, using phage technology.

Results: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo. In one of the two animal models of colorectal cancer studied (LS174T), CA IX imaging closely matched pimonidazole staining, with a preferential staining of tumour areas characterised by little vascularity and low perfusion. In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting. We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies.

Conclusion: The new human anti-CA IX antibodies are expected to be non-immunogenic in patients with cancer and may serve as broadly applicable reagents for the non-invasive imaging of hypoxia and for pharmacodelivery applications.

Show MeSH
Related in: MedlinePlus