Immunoprotective primary mesenchymal stem cells and methods

Abstract

Immunoprotective primary mesenchymal stems cells (IP-MSC) which episomally express immunoreactive polypeptides that specifically target a pathogen (e.g., an infectious species of virus, bacterium, or parasite) or toxin are described herein. The immunoreactive polypeptides can be, e.g., full antibodies, single-chain antibodies (ScFV), Fab or F(ab)2 antibody fragments, diabodies, tribodies, and the like). Optionally IP-MSC are trasfected to express one or more other immunomodulating polypeptides, e.g., a cytokine such as an interleukin (e.g., IL-2, IL-4, IL-6, IL-7, IL-9, and IL-12), an interferon (e.g., IFNα, IFβ, or IFNω), and the like, which can enhance the effectiveness of the immunoreactive polypeptides.

We claim: 
     
         1 . Immunoprotective primary mesenchymal stems cells (IP-MSC) that episomally express immunoreactive polypeptides that specifically target a pathogen or toxin; the IP-MSC being adipose-derived mesenchymal stem cells transfected with one or more episomal vectors encoding expressible immunoreactive polypeptides that specifically target the pathogen or toxin; wherein the immunoreactive polypeptides comprise amino acid sequences from an antigen-binding region of a neutralizing antibody specific for the pathogen or toxin; the antigen-binding region amino acid sequences being arranged to specifically bind to and neutralize the pathogen or toxin; wherein the pathogen is selected from the group consisting of a bacterial pathogen and a parasitic pathogen; the episomal vector includes an inducible apoptosis gene; the immunoreactive polypeptides comprise the complementarity determining regions of the antibody; and the one or more episomal vectors are non-infective, non-integrative, circular episomal vectors. 
     
     
         2 . The IP-MSC of  claim 1 , wherein the IP-MSC also express one or more immunomodulating agents selected from the group consisting of interleukins and interferons. 
     
     
         3 . The IP-MSC of  claim 2 , wherein the one or more immunomodulating agents are selected from the group consisting of IL-2, IL-4, IL-6, IL-7, IL-9, IL-12, IFNα, IFNβ, and IFNω. 
     
     
         4 . The IP-MSC of  claim 1 , wherein the immunoreactive polypeptides are selected from the group consisting of a full-length antibody, an antibody single-chain variable antibody fragment (ScFV), a monovalent antibody antigen-binding fragment (Fab), a divalent antibody antigen-binding fragment (F(ab′)2), a diabody, and a tribody. 
     
     
         5 . The IP-MSC of  claim 1 , wherein the one or more episomal vectors also encode a tetracycline-controlled transcriptional activation system for activating the inducible apoptosis gene. 
     
     
         6 . The IP-MSC of  claim 1 , wherein the immunoreactive polypeptides specifically target a bacterial pathogen from a genus selected from the group consisting of:  Bacillus, Bordetella, Borrelia, Brucella, Burkholderia, Campylobacter, Chlamydia, Chlamydophila, Clostridium, Corynebacterium, Enterococcus, Escherichia, Francisella, Haemophilus, Helicobacter, Legionella, Leptospira, Listeria, Mycobacterium, Mycoplasma, Neisseria, Pseudomonas, Rickettsia, Salmonella, Shigella, Staphylococcus, Streptococcus, Treponema, Vibrio , and  Yersinia.    
     
     
         7 . The IP-MSC of  claim 6 , wherein the immunoreactive polypeptides specifically target a protein from the bacterial pathogen selected from the group consisting of: outer membrane protein assembly factor BamA, translocation assembly module protein TamA, polypeptide-transport associated protein domain protein, a bacterial surface antigen D15, anthrax protective protein, anthrax lethal factor, anthrax edema factor;  Salmonella typhii  S1 Da,  Salmonella typhii  S1Db, cholera toxin, cholera heat shock protein,  Clostridium botulinum  antigen S, botulinum toxin,  Yersina pestis  F1 , Yersina pestis  V antigen,  Yersina pestis  YopH,  Yersina pestis  YopM,  Yersina pestis  YopD, and a bacterial plasminogen activation factor (Pla). 
     
     
         8 . The IP-MSC of  claim 1 , wherein the immunoreactive polypeptides specifically target a parasitic pathogen selected from the group consisting of:  Acanthamoeba, Anisakis, Ascaris lumbricoides, Balantidium coli , Cestoda (tapeworm), Chiggers,  Cochliomyia hominivorax, Entamoeba histolytica, Fasciola hepatica, Giardia lamblia , Hookworm,  Leishmania, Linguatula serrata , Liver fluke,  Loa loa, Paragonimus  (lung fluke), Pinworm,  Plasmodium falciparum, Schistosoma, Strongyloides stercoralis , Tapeworm,  Toxoplasma gondii, Trypanosoma , Whipworm, and  Wuchereria bancrofti.    
     
     
         9 . The IP-MSC of  claim 8 , wherein the immunoreactive polypeptides specifically target a protein from the parasitic pathogen selected from the group consisting of circumsporozoite protein (CSP), sporozoite surface protein (SSP2/TRAP), liver stage antigen 1 (LSA1), exported protein 1 (EXP 1), erythrocyte binding antigen 175 (EBA-175), cysteine-rich protective antigen (cyRPA),  Plasmodium  heat shock protein 70 (hsp70),  Schistosoma  Sm29, and  Schistosoma  signal transduction protein 14-3-3. 
     
     
         10 . The IP-MSC of  claim 1 , wherein the immunoreactive polypeptides specifically target a toxin selected from the group consisting of cholera toxin, botulinum toxin, anthrax lethal factor, and anthrax edema factor. 
     
     
         11 . A pharmaceutical composition for treating or preventing an infection caused by a bacterial pathogen, an infection caused by a parasitic pathogen, or toxicity caused by exposure to a toxin, the composition comprising the IP-MSC of  claim 1  in a pharmaceutically acceptable carrier. 
     
     
         12 . The composition of  claim 11 , wherein the immunoreactive polypeptides are selected from a full-length antibody, an antibody single-chain variable antibody fragment (ScFV), a monovalent antibody antigen-binding fragment (Fab), a divalent antibody antigen-binding fragment (F(ab′)2), a diabody, and a tribody. 
     
     
         13 . A method for treating or preventing an infection caused by a bacterial pathogen, the method comprising administering to a subject an effective dosage of the IP-MSC of  claim 1 , wherein the immunoreactive polypeptides specifically target the bacterial pathogen. 
     
     
         14 . The method of  claim 13 , wherein the bacterial pathogen is from a genus selected from the group consisting of:  Bacillus, Bordetella, Borrelia, Brucella, Burkholderia, Campylobacter, Chlamydia, Chlamydophila, Clostridium, Corynebacterium, Enterococcus, Escherichia, Francisella, Haemophilus, Helicobacter, Legionella, Leptospira, Listeria, Mycobacterium, Mycoplasma, Neisseria, Pseudomonas, Rickettsia, Salmonella, Shigella, Staphylococcus, Streptococcus, Treponema, Vibrio , and  Yersinia.    
     
     
         15 . The method of  claim 13 , wherein the immunoreactive polypeptides specifically target a protein selected from the group consisting of outer membrane protein assembly factor BamA, translocation assembly module protein TamA, polypeptide-transport associated protein domain protein, a bacterial surface antigen D15, anthrax protective protein, anthrax lethal factor, anthrax edema factor;  Salmonella typhii  S1 Da,  Salmonella typhii  S1Db, cholera toxin, cholera heat shock protein,  Clostridium botulinum  antigen S, botulinum toxin,  Yersina pestis  F1 , Yersina pestis  V antigen,  Yersina pestis  YopH,  Yersina pestis  YopM,  Yersina pestis  YopD, and a bacterial plasminogen activation factor (Pla). 
     
     
         16 . A method for treating or preventing an infection caused by a parasitic pathogen, the method comprising administering to a subject an effective dosage of the IP-MSC of  claim 1 , wherein the immunoreactive polypeptides specifically target the parasitic pathogen. 
     
     
         17 . The method of  claim 16 , wherein the parasitic pathogen is selected from the group consisting of:  Acanthamoeba, Anisakis, Ascaris lumbricoides, Balantidium coli , Cestoda (tapeworm), Chiggers,  Cochliomyia hominivorax, Entamoeba histolytica, Fasciola hepatica, Giardia lamblia , Hookworm,  Leishmania, Linguatula serrata , Liver fluke,  Loa loa, Paragonimus  (lung fluke), Pinworm,  Plasmodium falciparum, Schistosoma, Strongyloides stercoralis , Tapeworm,  Toxoplasma gondii, Trypanosoma , Whipworm, and  Wuchereria bancrofti.    
     
     
         18 . The method of  claim 16 , wherein the immunoreactive polypeptides specifically target a protein selected from the group consisting of circumsporozoite protein (CSP), sporozoite surface protein (SSP2/TRAP), liver stage antigen 1 (LSA1), exported protein 1 (EXP 1), erythrocyte binding antigen 175 (EBA-175), cysteine-rich protective antigen (cyRPA),  Plasmodium  heat shock protein 70 (hsp70),  Schistosoma  Sm29, and  Schistosoma  signal transduction protein 14-3-3. 
     
     
         19 . A method for treating or preventing toxicity caused by exposure to a toxin, the method comprising administering to a subject an effective dosage of the IP-MSC of  claim 1 , wherein the immunoreactive polypeptides specifically target the toxin. 
     
     
         20 . The method of  claim 19 , wherein the immunoreactive polypeptides specifically target a toxin selected from the group consisting of cholera toxin, botulinum toxin, anthrax lethal factor, and anthrax edema factor.