Abstract: Described herein is the use of phage display antibody engineering technology and synthetic peptide screening to identify SD1 and SD2, human single-domain antibodies to mesothelin. SD1 recognizes a conformational epitope at the C-terminal end (residues 539-588) of human mesothelin close to the cell surface. SD2 binds full-length mesothelin. To investigate SD1 as a potential therapeutic agent, a recombinant human Fc (SD1-hFc) fusion protein was generated. The SD1-hFc protein exhibits strong complement-dependent cytotoxicity (CDC), in addition to antibody-dependent cellular cytotoxicity (ADCC), against mesothelin-expressing tumor cells. Furthermore, the SD1-hFc protein causes significant tumor growth inhibition of tumor xenografts in nude mice. SD1 and SD2 are the first human single-domain antibodies targeting mesothelin-expressing tumors.

Abstract: Described herein is the use of rabbit hybridoma technology, along with a panel of truncated mesothelin domain fragments, to identify anti-mesothelin mAbs that bind specific regions of mesothelin. In one aspect of the present disclosure, the rabbit mAbs bind an epitope that is not part of Region I. In particular, the identified mAbs (YP187, YP223, YP218 and YP3) bind either Region II (391-486), Region III (487-581) or a native conformation of mesothelin with subnanomolar affinity. These antibodies do not compete for binding with the mesothelin-specific immunotoxin SS 1P or mesothelin-specific antibody MORAb-009. In another aspect, disclosed is a high-affinity rabbit mAb that binds Region I of mesothelin (YP158). YP158 binds native mesothelin protein in cancer cells and tissues with high affinity and specificity.

Abstract: The invention provides high affinity antibodies suitable for forming immunotoxins that inhibit the growth of cells expressing human glycoprotein NMB, including glioblastoma multiforme cells, anaplastic astrocytoma cells, anaplastic oligodendroglioma cells, oligodendroglioma cells, and melanoma cells. The antibodies may be formed in cells transformed with an isolated nucleic acid encoding a polypeptide comprising an antibody heavy chain variable region (“VH”) and an antibody light chain variable region (“VL”). Such nucleic acids are provided.

Abstract: We have constructed bispecific antibody engaging molecules which have one arm that specifically engages a tumor cell which expresses the human EGFRvIII mutant protein on its surface, and a second arm that specifically engages T cell activation ligand CD3. The engaging molecules are highly cytotoxic and antigen-specific. These are promising therapeutic agents.

Abstract: The invention provides a Pseudomonas exotoxin A (PE) comprising an amino acid sequence having a substitution of one or more B-cell and/or T-cell epitopes. The invention further provides related chimeric molecules, as well as related nucleic acids, recombinant expression vectors, host cells, populations of cells, and pharmaceutical compositions. Methods of treating or preventing cancer in a mammal, methods of inhibiting the growth of a target cell, methods of producing the PE, and methods of producing the chimeric molecule are further provided by the invention.

Abstract: The invention provides a chimeric antigen receptor (CAR) (a) an antigen binding domain of HN1 or SS, a transmembrane domain, and an intracellular T cell signaling domain, or (b) an antigen binding domain of SS1, a transmembrane domain, an intracellular T cell signaling domain, and a granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor 2 leader. Nucleic acids, recombinant expression vectors, host cells, populations of cells, antibodies, or antigen binding portions thereof, and pharmaceutical compositions relating to the CARs are disclosed. Methods of detecting the presence of cancer in a mammal and methods of treating or preventing cancer in a mammal are also disclosed.

Abstract: The present invention provides improved Pseudomonas Exotoxin A (PE) molecules with high cytotoxicity and reduced immunogenicity, compositions containing the improved (PE), and methods of use.

Abstract: POTE has recently been identified as a tumor antigen expressed in a variety of human cancers, including colon, ovarian, breast, prostate, lung and pancreatic cancer. Described herein are immunogenic POTE polypeptides, including modified POTE polypeptides, that bind MHC class I molecules. The immunogenic POTE polypeptides are capable of inducing an immune response against POTE-expressing tumor cells. Thus, provided herein is a method of eliciting an immune response in a subject, such as a subject having a type of cancer that expresses POTE.

Abstract: The invention provides mutated Pseudomonas exotoxins (PE) that have reduced immunogenicity compared to PEs containing the native sequence. The PEs of the invention have one or more individual mutations of positions of the native sequence of PE that reduce antibody binding to one or more PE epitopes. Nucleic acids encoding the mutated PEs, chimeric molecules comprising them, compositions comprising the chimeric molecules and methods of using them, are also provided.

Abstract: We tested the in vitro and in vivo efficacy of a recombinant bispecific immunotoxin that recognizes both EGFRwt and tumor-specific EGFRvIII receptors. A single chain antibody was cloned from a hybridoma and fused to toxin, carrying a C-terminal peptide which increases retention within cells. The binding affinity and specificity of the recombinant bispecific immunotoxin for the EGFRwt and the EGFRvIII proteins was measured. In vitro cytotoxicity was measured. In vivo activity of the recombinant bispecific immunotoxin was evaluated in subcutaneous models and compared to that of an established monospecific immunotoxin. In our preclinical studies, the bispecific recombinant immunotoxin, exhibited significant potential for treating brain tumors.

Abstract: POTE has recently been identified as a tumor antigen expressed in a variety of human cancers, including colon, ovarian, breast, prostate, lung and pancreatic cancer. Described herein are immunogenic POTE polypeptides, including modified POTE polypeptides, that bind MHC class I molecules. The immunogenic POTE polypeptides are capable of inducing an immune response against POTE-expressing tumor cells. Thus, provided herein is a method of eliciting an immune response in a subject, such as a subject having a type of cancer that expresses POTE.

Abstract: The invention provides mutated, cytotoxic forms of Pseudomonas exotoxin A (PE) comprising a furin cleavage sequence conjugated or fused directly to residues 395-613 of PE or variants of that sequence. These minimal forms of PE are smaller than previous cytotoxic forms of PE, reduce non-specific toxicity, and reduce immunogenicity due to domain II or domain Ib of PE. The invention further provides nucleic acids encoding said PEs, chimeric molecules containing them, and methods of use thereof.

Abstract: The invention provides a peptide comprising a human cytolytic T lymphocyte (CTL) epitope from the human tumor-associated antigen (TAA) New Gene Expressed in Prostate (NGEP), which can be used in vaccine prevention or therapy of prostate cancer, as well as a nucleic acid encoding the peptide, a vector comprising the nucleic acid, a cell comprising the peptide, nucleic acid, or vector, and compositions thereof.

Abstract: The disclosure provides a chimeric antigen receptor (CAR) comprising a) an antigen binding domain of HA22, a transmembrane domain, and an intracellular T cell signaling domain; or b) an antigen binding domain of BL22, a transmembrane domain, and an intracellular T cell signaling domain comprising CD28 and/or CD137. Nucleic acids, recombinant expression vectors, host cells, populations of cells, antibodies, or antigen binding portions thereof, and pharmaceutical compositions relating to the CARs are disclosed. Methods of detecting the presence of cancer in a mammal and methods of treating or preventing cancer in a mammal are also disclosed.

Abstract: The invention provides a Pseudomonas exotoxin A (PE) comprising an amino acid sequence having a substitution of one or more of amino acid residues E420, D463, Y481, L516, R563, D581, D589, and K606, wherein the amino acid residues are defined by reference to SEQ ID NO: 1. The invention further provides related chimeric molecules, as well as related nucleic acids, recombinant expression vectors, host cells, populations of cells, and pharmaceutical compositions. Methods of treating or preventing cancer in a mammal, methods of inhibiting the growth of a target cell, methods of producing the PE, and methods of producing the chimeric molecule are further provided by the invention.

Abstract: Mesothelin is a differentiation antigen present on the surface of ovarian cancers, mesotheliomas and several other types of human cancers. Because among normal tissues, mesothelin is only present on mesothelial cells, it represents a good target for antibody mediated delivery of cytotoxic agents. The present invention is directed to improved recombinant immunotoxins comprising anti-mesothelin antibodies, including Fv molecules with particularly high affinity for mesothelin, and a Pseudomonas Exotoxin moiety which has been modified to reduce its immunogenicity and protease sensitivity and providing a better cytotoxicity for cells which express mesothelin. The RITs are well-suited for the treatment of cancers of the ovary, stomach, squamous cells, mesotheliomas and other malignant cells expressing mesothelin.

Abstract: The invention provides a Pseudomonas exotoxin A (PE) comprising an amino acid sequence having a substitution of one or more B-cell and/or T-cell epitopes. The invention further provides related chimeric molecules, as well as related nucleic acids, recombinant expression vectors, host cells, populations of cells, and pharmaceutical compositions. Methods of treating or preventing cancer in a mammal, methods of inhibiting the growth of a target cell, methods of producing the PE, and methods of producing the chimeric molecule are further provided by the invention.

Abstract: Recombinant scFv-immunotoxins target tumor cells expressing human podoplanin but not podoplanin-negative or normal cells. The immunotoxins can be used for treatment of malignant glioma patients or any malignant tumor expressing podoplanin. One such immunotoxin comprises a modified Pseudomonas exotoxin (PE38) attached to the scFv antibody fragment. This immunotoxin can be used as a therapeutic drug for the treatment of malignant gliomas and other cancers.

Abstract: High affinity antibodies were made to gangliosides expressed on tumor cells. The antibodies can be used analytically, diagnostically, therapeutically, and theranostically. The antibodies may be used to target cytotoxic reagents to tumor cells, thus minimizing full-body toxicity. The antibodies may also be used with out added cytotoxin. The antibodies may be detectably labeled or labelable for analytic and diagnostic purposes. The combination of specificity and affinity of the antibodies render them particularly useful.

Abstract: Disclosed herein are isolated human monoclonal antibodies that specifically bind human CD22 with a dissociation constant (Kd) of 25 nM or less. Nucleic acids encoding these antibodies, expression vectors including these nucleic acid molecules, and isolated host cells that express the nucleic acid molecules are also disclosed. The antibodies can be used to detect human CD22 in a sample. In some cases, CD22 is soluble CD22. Methods of diagnosing a B-cell malignancy, or confirming a B-cell malignancy diagnosis, are disclosed herein that utilize these antibodies. Methods of treating a subject with a B-cell malignancy are also disclosed.