Compositions and Methods Related to Multimodal Therapeutic Cell Systems for Cancer Indications

Abstract

The invention includes compositions and methods related to multimodal therapies, e.g., for treating a cancer. A multimodal therapy described herein provides and/or administers a plurality of agents that function in a coordinated manner to provide a therapeutic benefit to a subject in need thereof, e.g., a subject having a cancer.

1 . An enucleated red blood cell, e.g., a reticulocyte, comprising a plurality of exogenous polypeptides, wherein a first and a second exogenous polypeptide of the plurality have agent-additive, agent-synergistic, multiplicative, independent function, localization-based, proximity-dependent, scaffold-based, multimer-based, or compensatory activity. 
     
     
         2 . An enucleated red blood cell, e.g., a reticulocyte, comprising a first exogenous polypeptide, a second exogenous polypeptide, and a third exogenous polypeptide. 
     
     
         3 . An enucleated red blood cell, e.g., a reticulocyte, comprising a first exogenous polypeptide and a second exogenous polypeptide, wherein:
 a) the first and second exogenous polypeptides act on the same target, wherein optionally the target is a cell surface receptor and/or an endogenous human protein;   b) the first exogenous polypeptide binds to a first endogenous human protein and the second exogenous polypeptide binds to a second endogenous human target protein, e.g., with a Kd of less than 500, 200, 100, 50, 20, 10, 5, 2, or 1 nM;   c) the first exogenous polypeptide acts on (e.g., binds) a first target, and the second exogenous polypeptide act on (e.g., binds) a second target, wherein the first and second targets are members of the same biological pathway, wherein optionally the targets are cell surface receptors, endogenous human proteins, or both;   d) the first exogenous polypeptide comprises a first pro-apoptotic polypeptide and the second exogenous polypeptide comprises a second pro-apoptotic polypeptide, e.g., a TRAIL receptor ligand, e.g., a TRAIL polypeptide;   e) the first and second exogenous polypeptides are in close proximity to each other, e.g., are less than 10, 7, 5, 4, 3, 2, 1, 0.5, 0.2, or 0.1 nm apart for a duration of at least 1, 2, 5, 10, 30, or 60 seconds; 1, 2, 5, 10, 30, or 60 minutes, or 1, 2, 3, 6, 12, or 14 hours;   f) the first and second exogenous polypeptides have a Kd of less than 500, 200, 100, 50, 20, 10, 5, 2, or 1 nM for each other;   g) the first exogenous polypeptide comprises an antigen-presenting polypeptide, e.g., an MHC molecule, e.g., an MHC class II molecule, and the second exogenous polypeptide comprises an antigen, e.g., a cancer antigen;   h) the first and second exogenous polypeptides act on different targets, wherein optionally at least one of the targets is a cell surface receptor and/or an endogenous human protein, e.g., the first exogenous polypeptide binds a first cell type, e.g., a cancer cell, and the second exogenous polypeptide binds a second cell type, e.g., an immune effector cell, e.g., a T cell;   i) the first exogenous polypeptide and the second exogenous polypeptide have an abundance ratio of about 1:1, from about 2:1 to 1:2, from about 5:1 to 1:5, from about 10:1 to 1:10, from about 20:1 to 1:20, from about 50:1 to 1:50, from about 100:1 to 1:100 by weight or by copy number;   j) the first exogenous polypeptide and the second exogenous polypeptide have a Kd for a first target and a second target, respectively, with a ratio of about 1:1, from about 2:1 to 1:2, from about 5:1 to 1:5, from about 10:1 to 1:10, from about 20:1 to 1:20, from about 50:1 to 1:50, from about 100:1 to 1:100;   k) the first exogenous polypeptide has a first activity (e.g., binding) towards a first target, and the second exogenous polypeptide has a second activity (e.g., binding) towards the first target, e.g., the first and second exogenous polypeptides bind a single target;   l) the first exogenous polypeptide acts on (e.g., binds) a first target and the second exogenous polypeptide acts on (e.g., binds) a second target, and the first and second targets are part of the same pathway, wherein optionally the first exogenous polypeptide acts on the first target and the second exogenous polypeptide acts on the second target simultaneously;   m) the first exogenous polypeptide acts on (e.g., binds) a first target and the second exogenous polypeptide acts on (e.g., binds) a second target, and the first and second targets are part of different pathways, wherein optionally the first and second pathways both act to promote a given cellular response;   n) the first exogenous polypeptide localizes the enucleated red blood cell to a desired site, e.g., a human cell, and the second exogenous polypeptide has a therapeutic activity, e.g., an immunomodulation activity such as a T cell activation activity, T cell inhibition activity, or antigen presenting activity;   o) the first exogenous polypeptide binds a first cell, e.g., a first cell type, e.g., a cancer cell, and the second exogenous polypeptide binds a second cell, e.g., a second cell type, e.g., an immune effector cell, e.g., a T cell;   p) the first exogenous polypeptide and the second exogenous polypeptide are non-human proteins;   q) the first exogenous polypeptide and the second exogenous polypeptide are both enzymes, e.g., biosynthetic enzymes;   r) the first exogenous polypeptide promotes formation of an intermediate molecule and the second exogenous polypeptide acts on the intermediate molecule; or   s) the first exogenous polypeptide and the second exogenous polypeptide act on successive steps of a pathway.   
     
     
         4 . The enucleated red blood cell of any of the preceding  claims , wherein the first and second exogenous polypeptides have agent-additive activity. 
     
     
         5 . The enucleated red blood cell of  claim 4 , wherein the first polypeptide binds a cancer cell (e.g., comprises an anti-EPCAM molecule) and the second exogenous polypeptide binds a cancer cell (e.g., comprises an anti-CD45 antibody molecule). 
     
     
         6 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have agent-synergistic activity. 
     
     
         7 . The enucleated red blood cell of  claim 6 , wherein the first exogenous polypeptide comprises a ligand for a first cellular receptor that mediates apoptosis (e.g., is a ligand for a TRAIL receptor, e.g., comprises a TRAIL polypeptide), and the second exogenous polypeptide comprises a ligand for a first cellular receptor that mediates apoptosis (e.g., is a ligand for a TRAIL receptor, e.g., comprises a TRAIL polypeptide). 
     
     
         8 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have multiplicative activity. 
     
     
         9 . The enucleated red blood cell of  claim 8 , wherein the first exogenous polypeptide comprises a T cell activation ligand of Table 2 or a T-cell activating variant (e.g., fragment) thereof, and the second exogenous polypeptide comprises a second T cell activation ligand of Table 2 or a T-cell activating variant (e.g., fragment) thereof. 
     
     
         10 . The enucleated red blood cell of  claim 8 , wherein the first exogenous polypeptide comprises an inhibitor of an inhibitory ligand of Table 3, or an inhibitory fragment or variant thereof, and the second exogenous polypeptide comprises a second inhibitor of an inhibitory ligand of Table 3, or an inhibitory fragment or variant thereof. 
     
     
         11 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have independent function activity. 
     
     
         12 . The enucleated red blood cell of  claim 11 , wherein the first exogenous polypeptide binds a first cytokine and the second exogenous polypeptide binds a second cytokine. 
     
     
         13 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have localization-based activity. 
     
     
         14 . The enucleated red blood cell of  claim 13 , wherein the first exogenous polypeptide comprises a targeting moiety that binds at or near a cancer cell (e.g., binds tumor neovasculature), and the second exogenous polypeptide has an anti-cancer function (e.g., comprises an enzyme, an inhibitor of angiogenesis, an immunostimulatory molecule, or a pro-apoptotic agent). 
     
     
         15 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have proximity-dependent activity. 
     
     
         16 . The enucleated red blood cell of  claim 15 , wherein proximity between the plurality of polypeptides, before, during, or after, interaction with a target moiety or moieties, confers a property or result which is not seen in the absence of such proximity in vivo or in vitro. 
     
     
         17 . The enucleated red blood cell of  claim 15 , wherein the first exogenous polypeptide interacts with, e.g., binds, a first target moiety, e.g., a first target cell polypeptide on a target cell (e.g., an immune effector cell, e.g., a T cell), and the second exogenous polypeptide interacts with, e.g., binds, a second target moiety, e.g., a second target cell polypeptide on the target cell (e.g., wherein binding of the first and second target cell polypeptide alters a biological property of the target cell). 
     
     
         18 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have scaffold-based activity. 
     
     
         19 . The enucleated red blood cell of  claim 18 , wherein the first polypeptide binds a cell surface marker of a cancer cell (e.g., CD19, EpCAM, CD20, CD45, EGFR, or HER2) and the second polypeptide binds a cell surface marker of an immune effector cell (e.g., CD3). 
     
     
         20 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have multimer-based activity. 
     
     
         21 . The enucleated red blood cell of  claim 20 , wherein the first exogenous polypeptide comprises an MHCII alpha chain and the second exogenous polypeptide comprises an MHCII beta chain polypeptide. 
     
     
         22 . The enucleated red blood cell of any of  claims 1-3 , wherein the first and second exogenous polypeptides have compensatory activity. 
     
     
         23 . The enucleated red blood cell of  claim 22 , wherein the first exogenous polypeptide is a therapeutic protein and the second exogenous polypeptide is an inhibitor of the first exogenous polypeptide, e.g., wherein the first exogenous polypeptide binds to a target more strongly than the first exogenous polypeptide binds to the second exogenous polypeptide. 
     
     
         24 . The enucleated red blood cell of  claim 22 , wherein the first exogenous polypeptide comprises an anti-CD40 antibody molecule and the second exogenous polypeptide comprises CD40 or a fragment or variant thereof. 
     
     
         25 . The enucleated red blood cell of any of the preceding  claims , wherein the first exogenous polypeptide promotes fusion of the red blood cell with a target cell and the second exogenous polypeptide is a polypeptide of any of Table 1, Table 2, or Table 3. 
     
     
         26 . The enucleated red blood cell of any of the preceding  claims , wherein the first and second exogenous polypeptides interact with one another, e.g., the first modifies, e.g., by cleavage or phosphorylation the second. 
     
     
         27 . The enucleated red blood cell of any of the preceding  claims , wherein the first and second exogenous polypeptides form a dimeric or multimeric protein. 
     
     
         28 . The enucleated red blood cell of any of the preceding  claims , which comprises at least 2 but no more than 5, 6, 7, 8, 9, or 10 different exogenous polypeptides, e.g., exogenous polypeptides that are encoded by one or more exogenous nucleic acids that are not retained by the enucleated red blood cell. 
     
     
         29 . The enucleated red blood cell of any of the preceding  claims , wherein the exogenous polypeptides are encoded by one or more exogenous nucleic acids that are not retained by the enucleated red blood cell. 
     
     
         30 . The enucleated red blood cell of any of the preceding  claims , wherein one or more (e.g., two or three) of the first, second, and optionally third exogenous polypeptides are transmembrane polypeptides or surface-anchored polypeptides. 
     
     
         31 . The enucleated red blood cell of any of the preceding  claims , wherein the first exogenous polypeptide interacts with, e.g., binds, a moiety on a target cell, and the second exogenous polypeptide alters a property of the target cell, e.g., kills or activates the target cell. 
     
     
         32 . The enucleated red blood cell of any of the preceding  claims , wherein the first exogenous polypeptide and the second exogenous polypeptide have an abundance ratio of about 1:1, from about 2:1 to 1:2, from about 5:1 to 1:5, from about 10:1 to 1:10, from about 20:1 to 1:20, from about 50:1 to 1:50, or from about 100:1 to 1:100 by weight or by copy number. 
     
     
         33 . The enucleated red blood cell of any of the preceding  claims , wherein both the first and second polypeptides have a stoichiometric mode of action, or both have a catalytic mode of action, and both are present at a similar abundance, e.g., about 1:1 or from about 2:1 to 1:2. 
     
     
         34 . The enucleated red blood cell of any of the preceding  claims , wherein the first exogenous polypeptide is more abundant than the second exogenous polypeptide by at least about 10%, 20%, 30%, 50%, or a factor of 2, 3, 4, 5, 10, 20, 50, or 100 (and optionally up to 10 or 100 fold) by weight or copy number. 
     
     
         35 . The enucleated red blood cell of any of the preceding  claims , wherein the first polypeptide has a stoichiometric mode of action and the second polypeptide has a catalytic mode of action, and the first polypeptide is more abundant than the second polypeptide. 
     
     
         36 . The enucleated red blood cell of any of the preceding  claims , which has one or more of the following characteristics:
 a) an osmotic fragility of less than 50% cell lysis at 0.3%, 0.35%, 0.4%, 0.45%, or 0.5% NaCl;   b) a cell volume of about 10-200 fL or a cell diameter of between about 1 micron and about 20 microns, between about 2 microns and about 20 microns, between about 3 microns and about 20 microns, between about 4 microns and about 20 microns, between about 5 microns and about 20 microns, between about 6 microns and about 20 microns, between about 5 microns and about 15 microns, or between about 10 microns and about 30 microns;   c) greater than 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% fetal hemoglobin; or at least about 20, 25, or 30 pg/cell of hemoglobin; or   d) phosphatidylserine content of the outer leaflet is less than 30%, 25%, 20%, 15%, 10%, or 5% as measured by Annexin V staining.   
     
     
         37 . The enucleated red blood cell of any of the preceding  claims , wherein at least one, e.g., all, of the plurality of exogenous polypeptides are glycosylated. 
     
     
         38 . The enucleated red blood cell of any of the preceding  claims , which is a reticulocyte. 
     
     
         39 . The enucleated red blood cell of any of the preceding  claims , wherein the exogenous polypeptide or polypeptides lack a sortase transfer signature such as LPXTG (SEQ ID NO: 17). 
     
     
         40 . The enucleated red blood cell of any of the preceding  claims , wherein an exogenous polypeptide, e.g., a fusion protein:
 i) at least 50, 60, 70, 80, 90, 95, or 99% of the fusion proteins on the surface of the erythroid cell have an identical sequence,   ii) at least 50, 60, 70, 80, 90, 95, or 99% of the fusion protein have the same transmembrane region,   iii) the fusion protein does not include a full length endogenous membrane protein, e.g., comprises a segment of a full length endogenous membrane protein, which segment lacks at least 1, 2, 3, 4, 5, 10, 20, 50, 100, 200, or 500 amino acids of the full length endogenous membrane protein;   iv) at least 50, 60, 70, 80, 90, 95, or 99 % of the fusion proteins do not differ from one another by more than 1, 2, 3, 4, 5, 10, 20, or 50 amino acids,   v) the exogenous polypeptide lacks a sortase transfer signature,   vi) the exogenous polypeptide comprises a moiety that is present on less than 1, 2, 3, 4, or 5 sequence distinct fusion polypeptides;   vii) the exogenous polypeptide is present as a single fusion polypeptide;   viii) the fusion protein does not contain Gly-Gly at the junction of an endogenous transmembrane protein and the moiety;   ix) the fusion protein does not contain Gly-Gly, or the fusion protein does not contain Gly-Gly, or does not contain Gly-Gly in an extracellular region, does not contain Gly-Gly in an extracellular region that is within 1, 2, 3, 4, 5, 10, 20, 50, or 100 amino acids of a transmembrane segment; or a combination thereof.   
     
     
         41 . An enucleated erythroid cell comprising:
 a first exogenous polypeptide that interacts with a target, and   a second exogenous polypeptide that modifies the target;   wherein one or more of:
 (a) the second exogenous polypeptide comprises a moiety that cleaves an antibody, e.g., that cleaves at a hinge region, a CH2 region, or between a hinge and CH2 region, e.g., an IdeS polypeptide; 
 (b) the second exogenous polypeptide comprises an enzyme (e.g., a protease) that modifies, e.g., is specific, e.g., binds to a site on target, binds (e.g., specifically) and modifies, e.g., covalently modifies, e.g., cleaves, or removes or attaches a moiety to, the target, wherein the target is optionally an antibody; 
 (c) the second exogenous polypeptide comprises a polypeptide, e.g., an enzyme, e.g., a protease, that modifies the secondary, tertiary, or quaternary structure of the target, and, in embodiments, alters, e.g., decreases or increases, the ability of the target to interact with another molecule, e.g., the first exogenous polypeptide or a molecule other than the first exogenous polypeptide, wherein optionally the target comprises an antibody; 
 (d) the second exogenous polypeptide comprises a polypeptide, e.g., an enzyme (e.g., a protease) that cleaves the target, e.g., a polypeptide, between a first target domain and a second target domain, e.g., a first target domain that binds a first substrate and a second target domain that binds a second substrate; 
 (e) the target is a polypeptide, a carbohydrate (e.g., a glycan), a lipid (e.g., a phospholipid), or a nucleic acid (e.g., DNA, or RNA); 
 (f) the first exogenous polypeptide binds a target, e.g., an antibody, but does not cleave, and the second exogenous polypeptide cleaves a bond e.g., a covalent bond, e.g., a covalent bond in the antibody; 
 (g) the target comprises an antibody and the first exogenous polypeptide binds the variable region of the antibody target; 
 (h) the target comprises an antibody and first exogenous polypeptide binds the constant region of the antibody target; 
 (i) the first exogenous polypeptide has an affinity for the target that is about 1-2 pM, 2-5 pM, 5-10 pM, 10-20 pM, 20-50 pM, 50-100 pM, 100-200 pM, 200-500 pM, 500-1000 pM, 1-2 nM, 2-5 nM, 5-10 nM, 10-20 nM, 20-50 nM, 50-100 nM, 100-200 nM, 200-500 nM, 500-1000 nM, 1-2 µM, 2-5 µM, 5-10 µM, 10-20 µM, 20-50 µM, or 50-100 µM; 
 (j) the second exogenous polypeptide has a K M  for the target of about 10 -1  - 10 -7  M, 10 -1  -10 -2  M, 10 -2  - 10 -3  M, 10 -3  - 10 -4  M, 10 -4  - 10 -5  M, 10 -5  - 10 -6  M, or 10 -6  - 10 -7  M; 
 (k) a ratio of the K d  of the first exogenous polypeptide for the target (measured in M) divided by the K M  of the second exogenous polypeptide for the target (measured in M) is about 1×10 -9  - 2×10 -9 , 2×10 -9  - 5×10 -9 , 5×10 -9  - 1×10 -8 , 1×10 -8  - 2×10 -8 , 2×10 -8  - 5×10 -8 , 5×10 -8 -1×10 -7 , 1×10 -7  - 2×10 -7 , 2×10 -7  - 5×10 -7 , 5×10 -7  - 1×10 -6 , 1×10 -6  - 2×10 -6 , 2×10 -6  - 5×10 -6 , 5×10 -6  - 1×10 -5 , 1×10 -5  - 2×10 -5 , 2×10 -5  - 5×10 -5 , 5×10 -5  - 1×10 -4 , 1x10 -4 , - 2x10 -4 , 2×10 -4 -5×10 -4 , 5×10 -4 - 1×10 -3 , 1×10 -3  - 2×10 -3 , 2×10 -3  - 5×10 -3 , 5×10 -3  - 1×10 -2 , 1×10 -2  - 2x10 -2 , 2×10 -2  - 5×10 -2 , 5×10 -2  - 1×10 -1 , 1×10 -1  - 2×10 -1 , 2×10 -1  - 5×10 -1 , or 5×10 -1  - 1; 
 (l) the observed reaction rate of the second exogenous polypeptide modifying the target is greater than the reaction rate of an enucleated cell which is similar but which lacks the first exogenous polypeptide under otherwise similar reaction conditions; 
 (m) a ratio of the average number of the first exogenous polypeptide on the erythroid cell to the average number of the second exogenous polypeptide on the erythroid cell is about 50:1, 20:1, 10:1, 8:1, 6:1, 4:1, 2:1, 1:1, 1:2, 1:4, 1:6, 1:8, 1:10, 1:20, or 1:50; 
 (n) affinity of the first exogenous polypeptide for the target is greater than the affinity of the first exogenous polypeptide for the modified (e.g., cleaved) target; 
 (o) a therapeutically effective dose of the enucleated erythroid cell is less than stoichiometry (e.g., less by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.9%, or 99.99%) to the amount of target in a subject’s peripheral blood at the time of administration; 
 (p) the number of enucleated erythroid cells in an effective dose, is less than (e.g., less by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.9%, or 99.99%) the number of targets, e.g., target molecules, in the subject’s peripheral blood at the time of administration; 
 (q) the number of second exogenous polypeptides comprised by a preselected amount of enucleated erythroid cells, e.g., an effective dose, or in vitro effective amount of enucleated erythroid cells, is less than (e.g., less by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.9%, or 99.99%) a reference value for targets, e.g., less than the number of targets in the peripheral blood of the subject at the time of administration; 
 (r) the number of first exogenous polypeptides comprised by a preselected amount of enucleated erythroid cells, e.g., an effective dose, or in vitro effective amount of enucleated erythroid cells, is less than (e.g., less by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.9%, or 99.99%) a reference value for targets, e.g., less than the number of targets in the peripheral blood of the subject at the time of administration; 
 (s) the number of first exogenous polypeptides and the number of second exogenous polypeptides comprised by a preselected amount of enucleated erythroid cells, e.g., an effective dose, enucleated erythroid cells, is each less than (e.g., less by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.9%, or 99.99%) a reference value for targets, e.g., less than the number of targets in the peripheral blood of the subject at the time of administration; 
 (t) the second exogenous polypeptide modifies (e.g. cleaves) the target with a K M  of at least 10 -1  M, 10 -2  M, 10 -3  M, 10 -4  M, 10 -5  M, 10 -6  M, or 10 -7  M; 
 (u) the second exogenous polypeptide comprises a chaperone; 
 (v) the first exogenous polypeptide comprises a surface-exposed portion and the second exogenous polypeptide comprises a surface exposed portion; or 
 (w) an effective amount of the enucleated erythroid cells is less than (e.g., less by 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 98%, 99%, 99.5%, 99.9%, or 99.99%) an effective amount of otherwise similar enucleated erythroid cells that lack the second exogenous polypeptide. 
   
     
     
         42 . The enucleated erythroid cell of  claim 41 , wherein (b) the second exogenous polypeptide comprises an enzyme (e.g., a protease) that modifies, e.g., is specific, e.g., binds to a site on target, binds (e.g., specifically) and modifies, e.g., covalently modifies, e.g., cleaves, or removes or attaches a moiety to, the target, wherein the target is optionally an antibody, e.g., an anti-drug antibody. 
     
     
         43 . The enucleated erythroid cell of  claim 41  or  42 , wherein the modification alters, e.g., increases or decreases, the ability of the target to interact with another molecule, e.g., the first exogenous polypeptide or a molecule other than the first exogenous polypeptide. 
     
     
         44 . The enucleated erythroid cell of any of  claims 41-43 , wherein (d) the second exogenous polypeptide comprises a polypeptide, e.g., an enzyme (e.g., a protease) that cleaves the target, e.g., a polypeptide, between a first target domain and a second target domain, e.g., a first target domain that binds a first substrate and a second target domain that binds a second substrate. 
     
     
         45 . The enucleated erythroid cell of  claim 44 , wherein the first target domain is released from the second target domain. 
     
     
         46 . The enucleated erythroid cell of  claim 44  or  45 , wherein cleavage alters the affinity of one or both of the first target domain for a first substrate and the affinity of the second target domain for a second substrate. 
     
     
         47 . The enucleated erythroid cell of any of  claims 41-46 , wherein the target comprises an antibody and the first target domain comprises one or more CDRs and the second target domain comprises a portion of the constant region, e.g., a Fc region. 
     
     
         48 . The enucleated erythroid cell of any of  claims 41-47 , wherein the target is other than an infectious component, e.g., other than a bacterial component, a viral component, a fungal component, or a parasitic component. 
     
     
         49 . The enucleated erythroid cell of any of  claims 41-48 , wherein the first exogenous polypeptide comprises a target-binding domain. 
     
     
         50 . The enucleated erythroid cell of any of  claims 41-49 , wherein the surface-exposed portion of the first exogenous polypeptide binds the target. 
     
     
         51 . The enucleated erythroid cell of any of  claims 41-50 , wherein the surface-exposed portion of the second exogenous polypeptide comprises enzymatic activity, e.g., protease activity. 
     
     
         52 . The enucleated erythroid cell of any of  claims 41-51 , wherein the surface-exposed portion of the second exogenous polypeptide enzymatically modifies, e.g., cleaves, the target. 
     
     
         53 . The enucleated erythroid cell of any of  claims 41-52 , wherein the target comprises an anti-drug antibody, the first exogenous polypeptide comprises a polypeptide to which the anti-drug antibody binds, and the second exogenous polypeptide comprises a protease that cleaves the anti-drug antibody to produce a Fab portion and an Fc portion. 
     
     
         54 . The enucleated erythroid cell of any of  claims 41-53 , wherein the enucleated red blood cell is capable of clearing the target from a subject’s body at a faster rate than an otherwise similar enucleated red blood cell that lacks the second exogenous polypeptide. 
     
     
         55 . The enucleated erythroid cell of any of  claims 41-54 , wherein the enucleated red blood cell is complexed with the target or a reaction product of the second exogenous protein acting on the target, e.g., during cleavage. 
     
     
         56 . An enucleated erythroid cell comprising:
 a first exogenous polypeptide comprising a transmembrane domain and a surface-exposed polypeptide capable of binding an anti-drug antibody, and   a second exogenous polypeptide comprising a transmembrane domain and a surface-exposed IdeS polypeptide.   
     
     
         57 . A preparation, e.g, a pharmaceutical preparation comprising a plurality of cells of any of  claims 1-56 , e.g., at least 10 8 , 10 9 , 10 10 , 10 11 , or 10 12  cells. 
     
     
         58 . A cell of any of  claims 1-56 , for treating a cancer. 
     
     
         59 . The cell of  claim 58 , wherein the cancer is selected from (ALL), acute myeloid leukaemia (AML), anal cancer, bile duct cancer, bladder cancer, bone cancer, bowel cancer, brain tumours, breast cancer, cancer of unknown primary, cancer spread to bone, cancer spread to brain, cancer spread to liver, cancer spread to lung, carcinoid, cervical cancer, choriocarcinoma, chronic lymphocytic leukaemia (CLL), chronic myeloid leukaemia (CML), colon cancer, colorectal cancer, endometrial cancer, eye cancer, gallbladder cancer, gastric cancer, gestational trophoblastic tumours (GTT), hairy cell leukaemia, head and neck cancer, Hodgkin lymphoma, kidney cancer, laryngeal cancer, leukaemia, liver cancer, lung cancer, NSCLC, lymphoma, melanoma skin cancer, mesothelioma, men’s cancer, molar pregnancy, mouth and oropharyngeal cancer, myeloma, nasal and sinus cancers, nasopharyngeal cancer, non-Hodgkin lymphoma (NHL), oesophageal cancer, ovarian cancer, pancreatic cancer, penile cancer, prostate cancer, rare cancers, rectal cancer, salivary gland cancer, secondary cancers, skin cancer (non-melanoma), soft tissue sarcoma, stomach cancer, testicular cancer, thyroid cancer, unknown primary cancer, uterine cancer, vaginal cancer, and vulval cancer.