Limits...
Theranostic nanoparticles carrying doxorubicin attenuate targeting ligand specific antibody responses following systemic delivery.

Yang E, Qian W, Cao Z, Wang L, Bozeman EN, Ward C, Yang B, Selvaraj P, Lipowska M, Wang YA, Mao H, Yang L - Theranostics (2015)

Bottom Line: Understanding the effects of immune responses on targeted delivery of nanoparticles is important for clinical translations of new cancer imaging and therapeutic nanoparticles.However, the production of ligand specific antibodies was markedly inhibited following systemic delivery of theranostic nanoparticles carrying a chemotherapy drug, doxorubicin.Targeted imaging and histological analysis revealed that lack of the ligand specific antibodies led to an increase in intratumoral delivery of targeted nanoparticles.

View Article: PubMed Central - PubMed

Affiliation: 1. Departments of Surgery, Emory University School of Medicine, Atlanta, GA 30322;

ABSTRACT
Understanding the effects of immune responses on targeted delivery of nanoparticles is important for clinical translations of new cancer imaging and therapeutic nanoparticles. In this study, we found that repeated administrations of magnetic iron oxide nanoparticles (IONPs) conjugated with mouse or human derived targeting ligands induced high levels of ligand specific antibody responses in normal and tumor bearing mice while injections of unconjugated mouse ligands were weakly immunogenic and induced a very low level of antibody response in mice. Mice that received intravenous injections of targeted and polyethylene glycol (PEG)-coated IONPs further increased the ligand specific antibody production due to differential uptake of PEG-coated nanoparticles by macrophages and dendritic cells. However, the production of ligand specific antibodies was markedly inhibited following systemic delivery of theranostic nanoparticles carrying a chemotherapy drug, doxorubicin. Targeted imaging and histological analysis revealed that lack of the ligand specific antibodies led to an increase in intratumoral delivery of targeted nanoparticles. Results of this study support the potential of further development of targeted theranostic nanoparticles for the treatment of human cancers.

Show MeSH

Related in: MedlinePlus

Detection of ligand specific antibody producing B cells in mouse spleens using ELISPOT assay. Balb/c mice bearing 4T1 mouse mammary tumors received tail vein injections of 200 pmol IONP, ScFvEGFR-IONP or ScFvEGFR-PEG-IONP, without or with carrying Dox, once per week for three weeks. The mice were then sacrificed and spleens collected for ELISPOT assay. A. Images of antibody-producing B cell spots (brown) in wells incubated with spleen cells from the mice. An ELISPOT reader was used to take the image. The number of brown colored dots represented the number of antibody producing B cells. M1, M2 and M3 were spleen cells from three mice in each group. B. Quantification of the amount of ScFvEGFR specific IgG or IgM producing B cells in mouse spleen. A total of 3x105 of spleen cells were added in each well for detection of targeting ligand specific antibody. The number was the mean of three mice in each group. Ab: antibody.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4265747&req=5

Figure 7: Detection of ligand specific antibody producing B cells in mouse spleens using ELISPOT assay. Balb/c mice bearing 4T1 mouse mammary tumors received tail vein injections of 200 pmol IONP, ScFvEGFR-IONP or ScFvEGFR-PEG-IONP, without or with carrying Dox, once per week for three weeks. The mice were then sacrificed and spleens collected for ELISPOT assay. A. Images of antibody-producing B cell spots (brown) in wells incubated with spleen cells from the mice. An ELISPOT reader was used to take the image. The number of brown colored dots represented the number of antibody producing B cells. M1, M2 and M3 were spleen cells from three mice in each group. B. Quantification of the amount of ScFvEGFR specific IgG or IgM producing B cells in mouse spleen. A total of 3x105 of spleen cells were added in each well for detection of targeting ligand specific antibody. The number was the mean of three mice in each group. Ab: antibody.

Mentions: To further determine the mechanisms of action of PEG-modified nanoparticles on enhanced antibody production and inhibition of antibody production by theranostic IONPs carrying Dox, we collected splenocytes from mice that received three systemic deliveries of control IONP, ScFvEGFR-IONP, ScFvEGFR-IONP-Dox, ScFvEGFR-PEG-IONP, or ScFvEGFR-PEG-IONP-Dox. ELISPOT assay was performed in a 96-well plate coated with ScFvEGFR, which allows the capture of B lymphocytes that produce ScFvEGFR specific IgM or IgG antibodies onto the plate. We found ScFvEGFR specific IgM or IgG antibody producing B cells in the spleens of mice that received systemic deliveries of ScFvEGFR-IONPs or ScFvEGFR-PEG-IONPs, but not in mice that received IONPs without any ligands (Figure 7A). Furthermore, the highest level of ScFvEGFR specific IgM or IgG producing B cells was detected in the spleens of mice that received ScFvEGFR-PEG-IONPs (Figure 7A & B). The mice that received ScFvEGFR-IONP-Dox or ScFvEGFR-PEG-IONP-Dox had significantly fewer ScFvEGFR specific IgG or IgM-producing B cells than that of the mice injected with ScFvEGFR-IONPs (p <0.05), or ScFvEGFR-PEG-IONPs (p <0.005). Additionally, we found that decreases in the levels of ScFvEGFR specific IgG or IgM-producing B cells in the mice that received the targeted IONP-Dox were not due to non-specific immune suppression effects or cytotoxic effect of Dox on B lymphocytes since ELISPOT assay revealed that the total numbers of IgG producing B cells were not decreased in the spleen (Figure 7A).


Theranostic nanoparticles carrying doxorubicin attenuate targeting ligand specific antibody responses following systemic delivery.

Yang E, Qian W, Cao Z, Wang L, Bozeman EN, Ward C, Yang B, Selvaraj P, Lipowska M, Wang YA, Mao H, Yang L - Theranostics (2015)

Detection of ligand specific antibody producing B cells in mouse spleens using ELISPOT assay. Balb/c mice bearing 4T1 mouse mammary tumors received tail vein injections of 200 pmol IONP, ScFvEGFR-IONP or ScFvEGFR-PEG-IONP, without or with carrying Dox, once per week for three weeks. The mice were then sacrificed and spleens collected for ELISPOT assay. A. Images of antibody-producing B cell spots (brown) in wells incubated with spleen cells from the mice. An ELISPOT reader was used to take the image. The number of brown colored dots represented the number of antibody producing B cells. M1, M2 and M3 were spleen cells from three mice in each group. B. Quantification of the amount of ScFvEGFR specific IgG or IgM producing B cells in mouse spleen. A total of 3x105 of spleen cells were added in each well for detection of targeting ligand specific antibody. The number was the mean of three mice in each group. Ab: antibody.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4265747&req=5

Figure 7: Detection of ligand specific antibody producing B cells in mouse spleens using ELISPOT assay. Balb/c mice bearing 4T1 mouse mammary tumors received tail vein injections of 200 pmol IONP, ScFvEGFR-IONP or ScFvEGFR-PEG-IONP, without or with carrying Dox, once per week for three weeks. The mice were then sacrificed and spleens collected for ELISPOT assay. A. Images of antibody-producing B cell spots (brown) in wells incubated with spleen cells from the mice. An ELISPOT reader was used to take the image. The number of brown colored dots represented the number of antibody producing B cells. M1, M2 and M3 were spleen cells from three mice in each group. B. Quantification of the amount of ScFvEGFR specific IgG or IgM producing B cells in mouse spleen. A total of 3x105 of spleen cells were added in each well for detection of targeting ligand specific antibody. The number was the mean of three mice in each group. Ab: antibody.
Mentions: To further determine the mechanisms of action of PEG-modified nanoparticles on enhanced antibody production and inhibition of antibody production by theranostic IONPs carrying Dox, we collected splenocytes from mice that received three systemic deliveries of control IONP, ScFvEGFR-IONP, ScFvEGFR-IONP-Dox, ScFvEGFR-PEG-IONP, or ScFvEGFR-PEG-IONP-Dox. ELISPOT assay was performed in a 96-well plate coated with ScFvEGFR, which allows the capture of B lymphocytes that produce ScFvEGFR specific IgM or IgG antibodies onto the plate. We found ScFvEGFR specific IgM or IgG antibody producing B cells in the spleens of mice that received systemic deliveries of ScFvEGFR-IONPs or ScFvEGFR-PEG-IONPs, but not in mice that received IONPs without any ligands (Figure 7A). Furthermore, the highest level of ScFvEGFR specific IgM or IgG producing B cells was detected in the spleens of mice that received ScFvEGFR-PEG-IONPs (Figure 7A & B). The mice that received ScFvEGFR-IONP-Dox or ScFvEGFR-PEG-IONP-Dox had significantly fewer ScFvEGFR specific IgG or IgM-producing B cells than that of the mice injected with ScFvEGFR-IONPs (p <0.05), or ScFvEGFR-PEG-IONPs (p <0.005). Additionally, we found that decreases in the levels of ScFvEGFR specific IgG or IgM-producing B cells in the mice that received the targeted IONP-Dox were not due to non-specific immune suppression effects or cytotoxic effect of Dox on B lymphocytes since ELISPOT assay revealed that the total numbers of IgG producing B cells were not decreased in the spleen (Figure 7A).

Bottom Line: Understanding the effects of immune responses on targeted delivery of nanoparticles is important for clinical translations of new cancer imaging and therapeutic nanoparticles.However, the production of ligand specific antibodies was markedly inhibited following systemic delivery of theranostic nanoparticles carrying a chemotherapy drug, doxorubicin.Targeted imaging and histological analysis revealed that lack of the ligand specific antibodies led to an increase in intratumoral delivery of targeted nanoparticles.

View Article: PubMed Central - PubMed

Affiliation: 1. Departments of Surgery, Emory University School of Medicine, Atlanta, GA 30322;

ABSTRACT
Understanding the effects of immune responses on targeted delivery of nanoparticles is important for clinical translations of new cancer imaging and therapeutic nanoparticles. In this study, we found that repeated administrations of magnetic iron oxide nanoparticles (IONPs) conjugated with mouse or human derived targeting ligands induced high levels of ligand specific antibody responses in normal and tumor bearing mice while injections of unconjugated mouse ligands were weakly immunogenic and induced a very low level of antibody response in mice. Mice that received intravenous injections of targeted and polyethylene glycol (PEG)-coated IONPs further increased the ligand specific antibody production due to differential uptake of PEG-coated nanoparticles by macrophages and dendritic cells. However, the production of ligand specific antibodies was markedly inhibited following systemic delivery of theranostic nanoparticles carrying a chemotherapy drug, doxorubicin. Targeted imaging and histological analysis revealed that lack of the ligand specific antibodies led to an increase in intratumoral delivery of targeted nanoparticles. Results of this study support the potential of further development of targeted theranostic nanoparticles for the treatment of human cancers.

Show MeSH
Related in: MedlinePlus