Abstract: The present invention provides a clinically applicable method of stem cell transplantation that facilitates engraftment and reconstitutes immunocompetence of the recipient without requiring radiotherapy or chemotherapy, and without development of GVHD or graft rejection. Aspects of the present invention are based on the discovery that the depletion of the endogenous stem cell niche facilitates efficient engraftment of stem cells into that niche. In particular, the present invention combines the use of selective ablation of endogenous stem cells with a combination of antibodies specific for CD117, and agents that modulate immunoregulatory signaling pathways, e.g. agonists of immune costimulatory molecules, in combination with the administration to the recipient of exogenous stem cells, resulting in efficient, long-term engraftment, even in immunocompetent recipients.

Abstract: Methods are provided for targeting cells for depletion, including without limitation tumor cells, in a regimen comprising contacting the targeted cells with a combination of agents that modulate immunoregulatory signaling. Immunoregulatory modulating agents include (i) an agent that blockades CD47 activity; and (ii) an agent that agonizes an immune costimulatory molecule, e.g. CD137. The regimen may further comprise an agent that specifically binds to the target cell, e.g. an antibody or biologically active fragment or derivative thereof. The level of depletion of the targeted cell is enhanced relative to a regimen in which a single immunoregulatory modulating agent is used; and the effect may be synergistic relative to a regimen in which a single immunoregulatory modulating agent is used.

Abstract: Methods are provided for targeting cells for depletion, including without limitation tumor cells, in a regimen comprising contacting the targeted cells with a combination of agents that modulate immunoregulatory signaling. Immunoregulatory modulating agents include (i) an agent that blockades CD47 activity; and (ii) an agent that agonizes an immune costimulatory molecule, e.g. CD137. The regimen may further comprise an agent that specifically binds to the target cell, e.g. an antibody or biologically active fragment or derivative thereof. The level of depletion of the targeted cell is enhanced relative to a regimen in which a single immunoregulatory modulating agent is used; and the effect may be synergistic relative to a regimen in which a single immunoregulatory modulating agent is used.

Abstract: Methods are provided for targeting cells for depletion, including without limitation tumor cells, in a regimen comprising contacting the targeted cells with a combination of agents that modulate immunoregulatory signaling. Immunoregulatory modulating agents include (i) an agent that blockades CD47 activity; and (ii) an agent that agonizes an immune costimulatory molecule, e.g. CD137. The regimen may further comprise an agent that specifically binds to the target cell, e.g. an antibody or biologically active fragment or derivative thereof. The level of depletion of the targeted cell is enhanced relative to a regimen in which a single immunoregulatory modulating agent is used; and the effect may be synergistic relative to a regimen in which a single immunoregulatory modulating agent is used.

Abstract: The present invention provides a clinically applicable method of stem cell transplantation that facilitates engraftment and reconstitutes immunocompetence of the recipient without requiring radiotherapy or chemotherapy, and without development of GVHD or graft rejection. Aspects of the present invention are based on the discovery that the depletion of the endogenous stem cell niche facilitates efficient engraftment of stem cells into that niche. In particular, the present invention combines the use of selective ablation of endogenous stem cells with a combination of antibodies specific for CD117, and agents that modulate immunoregulatory signaling pathways, e.g. agonists of immune costimulatory molecules, in combination with the administration to the recipient of exogenous stem cells, resulting in efficient, long-term engraftment, even in immunocompetent recipients.

Abstract: The present invention provides a clinically applicable method of stem cell transplantation that facilitates engraftment and reconstitutes immunocompetence of the recipient without requiring radiotherapy or chemotherapy, and without development of GVHD or graft rejection. Aspects of the present invention are based on the discovery that the depletion of the endogenous stem cell niche facilitates efficient engraftment of stem cells into that niche. In particular, the present invention combines the use of selective ablation of endogenous stem cells with a combination of antibodies specific for CD117, and agents that modulate immunoregulatory signaling pathways, e.g. agonists of immune costimulatory molecules, in combination with the administration to the recipient of exogenous stem cells, resulting in efficient, long-term engraftment, even in immunocompetent recipients.

Abstract: Methods are provided for targeting cells for depletion, including without limitation tumor cells, in a regimen comprising contacting the targeted cells with a combination of agents that modulate immunoregulatory signaling. Immunoregulatory modulating agents include (i) an agent that blockades CD47 activity; and (ii) an agent that agonizes an immune costimulatory molecule, e.g. CD137. The regimen may further comprise an agent that specifically binds to the target cell, e.g. an antibody or biologically active fragment or derivative thereof. The level of depletion of the targeted cell is enhanced relative to a regimen in which a single immunoregulatory modulating agent is used; and the effect may be synergistic relative to a regimen in which a single immunoregulatory modulating agent is used.

Abstract: Methods are provided for targeting cells for depletion, including without limitation tumor cells, in a regimen comprising contacting the targeted cells with a combination of agents that modulate immunoregulatory signaling. Immunoregulatory modulating agents include (i) an agent that blockades CD47 activity; and (ii) an agent that agonizes an immune costimulatory molecule, e.g. CD137. The regimen may further comprise an agent that specifically binds to the target cell, e.g. an antibody or biologically active fragment or derivative thereof. The level of depletion of the targeted cell is enhanced relative to a regimen in which a single immunoregulatory modulating agent is used; and the effect may be synergistic relative to a regimen in which a single immunoregulatory modulating agent is used.

Abstract: The present invention provides a clinically applicable method of stem cell transplantation that facilitates engraftment and reconstitutes immunocompetence of the recipient without requiring radiotherapy or chemotherapy, and without development of GVHD or graft rejection. Aspects of the present invention are based on the discovery that the depletion of the endogenous stem cell niche facilitates efficient engraftment of stem cells into that niche. In particular, the present invention combines the use of selective ablation of endogenous stem cells with a combination of antibodies specific for CD117, and agents that modulate immunoregulatory signaling pathways, e.g. agonists of immune costimulatory molecules, in combination with the administration to the recipient of exogenous stem cells, resulting in efficient, long-term engraftment, even in immunocompetent recipients.

Abstract: The present invention provides a clinically applicable method of stem cell transplantation that facilitates engraftment and reconstitutes immunocompetence of the recipient without requiring radiotherapy or chemotherapy, and without development of GVHD or graft rejection. Aspects of the present invention are based on the discovery that the depletion of the endogenous stem cell niche facilitates efficient engraftment of stem cells into that niche. In particular, the present invention combines the use of selective ablation of endogenous stem cells with a combination of antibodies specific for CD117, and agents that modulate immunoregulatory signaling pathways, e.g. agonists of immune costimulatory molecules, in combination with the administration to the recipient of exogenous stem cells, resulting in efficient, long-term engraftment, even in immunocompetent recipients.

Abstract: The present invention provides a clinically applicable method of stem cell transplantation that facilitates engraftment and reconstitutes immunocompetence of the recipient without requiring radiotherapy or chemotherapy, and without development of GVHD or graft rejection. Aspects of the present invention are based on the discovery that the depletion of the endogenous stem cell niche facilitates efficient engraftment of stem cells into that niche. In particular, the present invention combines the use of selective ablation of endogenous stem cells with a combination of antibodies specific for CD117, and agents that modulate immunoregulatory signaling pathways, e.g. agonists of immune costimulatory molecules, in combination with the administration to the recipient of exogenous stem cells, resulting in efficient, long-term engraftment, even in immunocompetent recipients.

Abstract: Purchase of information items from a merchant over the Internet or other network is implemented so as to ensure that the merchant is unable to identify the particular information item(s) purchased by a user. The user when considering purchase of a given information item is permitted to access a corresponding signed ciphertext of that item. The signed ciphertext in an illustrative embodiment includes a first ciphertext portion in the form of a symmetric key encrypted using a public key associated with the merchant, a second ciphertext portion corresponding to the information item encrypted using the symmetric key, an unencrypted description of the information item, and a tag corresponding to a signature. The user requests purchase of the information item by sending a blinded version of the first ciphertext portion to a payment server along with an appropriate payment. The payment server decrypts the blinded version of the first ciphertext portion and returns the resulting symmetric key to the user.

Abstract: A fast encryption method particularly useful for long message lengths is provided. A message m is encrypted using a transmitter secret key z to form a quantity E. A transmitter processor prepares a quadruplet (anew, bnew,snew, E) where: anew=z*ycmodulo p; bnew=gcmodulo p; snew=signaturec(anew,bnew,E). As in previous embodiments y=gxmodulo p is the public key and x is the receiver secret key. The parameters g, x, and p according to methods known to a person skilled in the art and the parameter g is a generator of the group Gp. The parameter c is a random number. The transmitter processor sends the quadruplet (anew, bnew,snew, E) to a receiver processor. The receiver processor verifies the signature on snew using methods known in the art. The receiver processor then decrypts anew and bnew using the receiver secret key x to get the transmitter secret key z, i.e. in the following manner z=anew/bnewx. The receiver processor uses the transmitter secret key z to decrypt E to get the message M.

Abstract: Purchase of information items from a merchant over the Internet or other network is implemented so as to ensure that the merchant is unable to identify the particular information item(s) purchased by a user. The user when considering purchase of a given information item is permitted to access a corresponding signed ciphertext of that item. The signed ciphertext in an illustrative embodiment includes a first ciphertext portion in the form of a symmetric key encrypted using a public key associated with the merchant, a second ciphertext portion corresponding to the information item encrypted using the symmetric key, an unencrypted description of the information item, and a tag corresponding to a signature. The user requests purchase of the information item by sending a blinded version of the first ciphertext portion to a payment server along with an appropriate payment. The payment server decrypts the blinded version of the first ciphertext portion and returns the resulting symmetric key to the user.