Humanization of JAA-F11, a Highly Specific Anti-Thomsen-Friedenreich Pancarcinoma Antibody and InVitro Efficacy Analysis

JAA-F11 is a highly specific mouse monoclonal to the Thomsen-Friedenreich Antigen (TF-Ag) which is an alpha-O-linked disaccharide antigen on the surface of ~80% of human carcinomas, including breast, lung, colon, bladder, ovarian, and prostate cancers, and is cryptic on normal cells. JAA-F11 has potential, when humanized, for cancer immunotherapy for multiple cancer types. Humanization of JAA-F11, was performed utilizing complementarity determining regions grafting on a homology framework. The objective herein is to test the specificity, affinity and biology efficacy of the humanized JAA-F11 (hJAA-F11). Using a 609 target glycan array, 2 hJAA-F11 constructs were shown to have excellent chemical specificity, binding only to TF-Ag alpha-linked structures and not to TF-Ag beta-linked structures. The relative affinity of these hJAA-F11 constructs for TF-Ag was improved over the mouse antibody, while T20 scoring predicted low clinical immunogenicity. The hJAA-F11 constructs produced antibody-dependent cellular cytotoxicity in breast and lung tumor lines shown to express TF-Ag by flow cytometry. Internalization of hJAA-F11 into cancer cells was also shown using a surface binding ELISA and confirmed by immunofluorescence microscopy. Both the naked hJAA-F11 and a maytansine-conjugated antibody (hJAA-F11-DM1) suppressed in vivo tumor progression in a human breast cancer xenograft model in SCID mice. Together, our results support the conclusion that the humanized antibody to the TF-Ag has potential as an adjunct therapy, either directly or as part of an antibody drug conjugate, to treat breast cancer, including triple negative breast cancer which currently has no targeted therapy, as well as lung cancer.

Abstract 576: Immunohistochemistry and radioimaging with hJAA-11 antibody to the Thomsen-Friedenreich antigen: Potential theranostic application for breast cancer

Theranostics through the utilization of immunohistochemistry followed by radioimaging to determine if metastatic foci will react with a therapeutic antibody will allow for the selection of the patient population that will most benefit from this immunotherapy. The Thomsen-Friedenreich antigen (TF-Ag) has been shown to be involved in ∼90% of carcinomas, specifically breast carcinomas, making it a suitable target for radioimaging and therapy. The anti-TF-Ag antibody, JAA-F11, a mouse monoclonal antibody (mAb), has had success in localization, blocking metastasis, and inhibiting cell proliferation, and binds to ∼80% of breast cancer cell lines, without preference to receptor status. This is significant since the triple negative breast cancer (ER-/PR-/HER2-) has no current targeted treatment. Studies are extended to human breast cancer tissue microarray immunohistochemical (IHC) analysis, which was scored blindly by a pathologist on a semi- quantitative scale. JAA-F11 stained approximately 76% of all breast cancer specimens, which included cases of mucinous, medullary, invasive ductal and neuroendocrine carcinomas. The staining observed was irrespective of receptor status, whereas in normal breast tissue, staining was either absent or very weak/weak. In addition, all available matched lymph node metastasis stained, with greater intensity observed in 39% of cases. JAA-F11 IHC studies performed on human normal organ tissue arrays, showed staining that for the most part was not significantly different from staining obtained with isotype control antibody, or was observed in areas that would not be therapeutically accessible. Furthermore, in an additional IHC study, preliminary results suggest that JAA-F11 significantly stained other carcinomas including those of the colon, bladder, ovary and prostate. In vitro studies show that the humanized JAA-F11 (hJAA-F11) has similar chemical specificity and higher affinity towards the TF-Ag. Imaging studies were performed in a BALB/c mouse breast cancer model with the hJAA-F11 to determine biological reactivity and to predict the feasibility of theranostic imaging prior to therapy. After ∼10 days of tumor growth, mice pretreated with cold iodine water and rabbit IgG to inhibit binding to Fc receptors, were given tail vein injections of hJAA-F11 conjugated with [124]-I. Clear tumor images were obtained up to 144 hours post injection. Biodistribution analysis has provided further results indicating increased%ID/g (7.0±3.9%) in tumor tissue as compared to healthy tissues (brain%ID/g to be 0.21±.09, stomach 0.80±0.19%, and bone 0.90±2.4%). Results support that the hJAA-F11 antibody can be used in a multi-step theranostic approach, with analysis of tumor binding in IHC, followed by imaging to determine in vivo tumor targeting prior to direct immunotherapy or antibody drug conjugate therapy with hJAA-F11.

Citation Format: Loukia Karacosta, Holly Johnson, Julia Abdullah, Taylor Chrisikos, Rachel Ludwig, Bradley Turner, Swetha Tati, Diala Ghazal, Munnawar Sajjad, Stephen Koury, Susan Morey, Julie Adams, Kate Rittenhouse-Olson. Immunohistochemistry and radioimaging with hJAA-11 antibody to the Thomsen-Friedenreich antigen: Potential theranostic application for breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 576.

Preclinical studies with JAA-F11 anti-Thomsen-Friedenreich monoclonal antibody for human breast cancer

ABSTRACT: 

Aim: The Thomsen-Friedenreich antigen (TF-Ag) is a disaccharide hidden on normal cells, but selectively exposed on the surface of breast, colon, prostate and bladder cancer cells. JAA-F11, a highly specific monoclonal antibody to TF-Ag, reduces metastasis and prolongs survival in a mouse model. In addition,124I-JAA-F11 localizes 4T1 tumors in mice. These studies continue translation of JAA-F11 to human breast cancer. Materials & methods & results: Of the 41 human breast cancer cell lines tested, 78% were positive for reactivity with JAA-F11 by whole-cell enzyme immunoassay and positivity occurred unrelated to estrogen, progesterone or HER2 receptor status. JAA-F11 inhibited the growth rate of the human cancer cell lines tested. At 1 h, approximately 80% of JAA-F11 internalized in the three cell lines tested. 124I-JAA-F11 specifically imaged human triple-negative tumors in mice by microPET. Conclusion: The results highlight the potential that humanized JAA-F11 may have for immunotherapy and drug conjugate therapy in breast cancer patients.

Direct effects of conjugated linoleic acid isomers on P815 mast cells in vitro

Conjugated linoleic acid (CLA) is a dietary fatty acid which causes extensive remodeling and mast cell recruitment in the mouse mammary gland. Two CLA isomers, 9,11- and 10,12-CLA, have differing effects in vivo, with only 10,12-CLA increasing mast cell number. The purpose of this project is to test the hypothesis that CLA acts directly on the mast cell. The P815 mastocytoma cell line was assayed for the effects of CLA on mast cell number, proliferation, apoptosis, and differentiation. Both CLA isomers decreased viable mast cell number, with no effect on membrane integrity, or cell cycle distribution. 10,12-CLA induced an increase in apoptosis, assessed by Annexin-FITC binding. Both isomers increased mast cell granularity, and secretion of MMP-9. The complex effects of CLA isomers on mast cells in the mammary gland are distinct from direct effects on mast cells in vitro, and may require interactions between multiple cell types present in vivo.

Differential gene expression during terminal erythroid differentiation

Terminal erythroid differentiation in mammals is the process whereby nucleated precursor cells accumulate erythroid-specific proteins such as hemoglobin, undergo extensive cellular and nuclear remodeling, and ultimately shed their nuclei to form reticulocytes, which then become mature erythrocytes in the circulation. Little is known about the mechanisms that enable erythroblasts to undergo such a transformation. We hypothesized that genes involved in these mechanisms were likely expressed at restricted times during the differentiation process and used differential display reverse transcriptase polymerase chain reaction as a first step in identifying such genes. We identified three differentially expressed cDNAs that we termed late erythroblast (LEB) 1-3. None of these cDNAs were previously identified as being expressed in erythroblasts and their patterns of expression indicated they are likely to be involved in the differentiation process. LEB-1 cDNA was derived from the gene A330102K04Rik (approved gene symbol Apoll1), and shares homology with members of the apolipoprotein L family in humans. LEB-3 cDNA was derived from the novel gene D930015E06Rik, that has no known function. LEB-2 cDNA was derived from the gene ranBP16 (approved gene symbol Xpo7), a nuclear exportin. D930015E06Rik mRNA is also strongly expressed in the testis and was localized to a region of the seminiferous tubule where secondary spermatocytes and early spermatids are found, suggesting a role for D930015E06Rik in spermatogenesis as well as terminal erythroid differentiation. We have thus identified three genes not previously described as being expressed in erythroblasts that could be relevant in elucidating mechanisms involved in terminal erythroid differentiation.

Tumor immunolocalization using 124 I-iodine-labeled JAA-F11 antibody to Thomsen-Friedenreich alpha-linked antigen

Clinical immunolocalization has been attempted by others with an anti-Thomsen-Friedenreich antigen (TF-Ag) mAb that bound both alpha- and beta-linked TF-Ag. In this report, 124 I-labeled mAb JAA-F11 specific for alpha-linked TF-Ag showed higher tumor specificity in in vivo micro-positron emission tomography (micro-PET) of the mouse mammary adenocarcinoma line, 4T1, showing no preferential uptake by the kidney. Labeled product remained localized in the tumor for at least 20 days. Glycan array analysis showed structural specificity of the antibody.

Erythropoietin production by interstitial cells of hypoxic monkey kidneys

Previous studies which demonstrated that interstitial cells of the peritubular capillary bed of the kidneys are the site of erythropoietin (Epo) production have been performed in non-primate species. In this study, kidneys from adult rhesus monkeys exposed to 18 h hypoxia (0.42 atm) with high serum (5685 mU/ml) and kidney (814 mU/g. includes serum EPO in the kidney) levels of Epo were compared with a kidney from a nonhypoxic normal rhesus monkey. Localization of Epo mRNA by in situ hybridization was carried out with either anti-sense or sense RNA probes generated from a 645 base pair KpnI-BgIII fragment of a monkey Epo cDNA. Epo mRNA was demonstrated only in interstitial cells in the peritubular capillary bed of the hypoxic and normal monkey kidneys utilizing the antisense probe. The finding that the same type of cell that produces EPO in mice, rats and sheep also produces EPO in a higher primate species strongly supports the contention that renal interstitial cells also produce EPO in the human.

Teaching dietetic interns to write for lay and professional audiences

The University of Iowa Hospitals and Clinics Dietetic Internship Program has developed a series of workshops and assignments to enhance the writing skills of interns. Three workshops cover basic writing skills, development of materials for the lay public, and basic elements of journalistic writing for professional audiences. The interns received a variety of assignments throughout the year to build competencies learned in these workshops. Evaluation forms have been developed to make assessing the assignments easier for the instructors and to give feedback to the interns. Evaluation reports from interns and graduates indicate that the program is effective and appreciated.