Abstract: The invention features methods for altering the immunomodulatory activity of compositions containing peripheral blood mononuclear cells. The methods include the steps of contacting PBMCs with an amount of an aziridino-containing compound effective to react with and modify the PBMC nucleic acid.

Abstract: Methods of inactivating contaminants of a biological matrix are disclosed. The methods include the steps of: (a) contacting a biological matrix with an inactivating agent including an aziridino moiety, where a portion of the agent reacts with and inactivates the contaminant, and a portion of the agent remains unreacted; (b) contacting the product of step (a) with a solid support including at least 1 quenching moiety attached to the solid support through covalent bonds, under conditions and for a time sufficient to allow the unreacted agent to bond covalently to the quenching moiety; and (c) separating the solid support and the unreacted agent from the biological matrix, where the unreacted agent is attached to the solid support through covalent bonds.

Abstract: Disclosed is a method for reducing the amount of extracellular fluid in a blood cell suspension. The method includes providing a large volume of a blood cell suspension that includes blood cells and extracellular fluid. The blood cell suspension is washed with a wash solution under conditions sufficient to lower the concentration of the extracellular fluid in the blood cell composition at least 103-fold relative to the amount of extracellular fluid in the blood cell suspension. The method can also be used to lower the concentration of analytes (such as prions) in the blood cell suspension. Also provided is a blood cell suspension produced by the washing method.

Abstract: The invention features a method of inactivating a contaminant, such as a virus, of a biological composition. The method includes the steps of: (a) contacting the biological composition with an inactivating agent including an aziridino moiety or a haloderivative salt thereof, where a portion of the agent reacts with and inactivates the contaminant, and a portion of the agent remains unreacted; (b) contacting the product of step (a) with a composition which includes one quenching moiety under conditions and for a time sufficient to allow the inactivating agent to bond covalently to the quenching moiety; and (c) separating the quenching moiety and the quenched inactivating agent from the biological composition.

Abstract: Methods of inactivating contaminants of a biological matrix are disclosed. The methods include the steps of: (a) contacting a biological matrix with an inactivating agent including an aziridino moiety, where a portion of the agent reacts with and inactivates the contaminant, and a portion of the agent remains unreacted; (b) contacting the product of step (a) with a solid support including at least 1 quenching moiety attached to the solid support through covalent bonds, under conditions and for a time sufficient to allow the unreacted agent to bond covalently to the quenching moiety; and (c) separating the solid support and the unreacted agent from the biological matrix, where the unreacted agent is attached to the solid support through covalent bonds.

Abstract: Methods and compositions for selectively inactivating viruses in biological compositions, including contacting the composition with an organic solvent and an ethyleneimine oligomer inactivating agent, are disclosed.

Abstract: The invention features a method for inactivating microorganisms such as viruses and bacteria in a preparation of purified mammalian cells which, when mature, lack a nucleus (e.g., red blood cells or platelets). The method includes contacting the preparation with ethyleneimine dimer under viral inactivating conditions for a period of time sufficient to inactivate at least some of the microorganismsin the preparation. Also disclosed is a method for removing ethyleneimine dimer from a treated biological composition following inactivation, without the addition of any quenching agent.

Abstract: Methods and compositions for selectively modifying nucleic acid molecules in biological compositions, including contacting the composition with an inactivating agent having the formula: where each of R1, R2, R3, R4, R6, R7, and R8 is, independently, H or a monovalent hydrocarbon moiety containing between 1 and 4 carbon atoms, inclusive, provided that R1, R2, R3, R4, R6, R7, and R8 cannot all be H; R5 is a divalent hydrocarbon moiety containing between 2 and 4 carbon atoms, inclusive; X is a pharmaceutically acceptable counter-ion; and n is an integer between 2 and 10, inclusive are disclosed.

Abstract: Methods and compositions for the inactivation and removal of contaminants of a biological composition are disclosed. The methods include the steps of: (a) contacting the biological composition with an inactivating agent including an aziridino moiety, such as ethyleneimine, an oligomer of ethyleneimine, or a haloderivative salt of either ethyleneimine or an oligomer of ethyleneimine, where a portion of the agent reacts with and inactivates the contaminant, and a portion of the agent remains unreacted; (b) contacting the product of step (a) with a lipophilic quenching agent including at least one quenching moiety attached to a lipophilic moiety, under conditions and for a time sufficient to allow the unreacted agent to bond covalently to the quenching moiety; and (c) separating the lipophilic quenching agent and the quenched inactivating agent from the biological composition.

Abstract: Methods and compositions for selectively modifying nucleic acid molecules in biological compositions, including contacting the composition with an inactivating agent having the formula: ##STR1## where each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.6, R.sub.7, and R.sub.8 is, independently, H or a monovalent hydrocarbon moiety containing between 1 and 4 carbon atoms, inclusive, provided that R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.6, R.sub.7, and R.sub.8 cannot all be H; R.sub.5 is a divalent hydrocarbon moiety containing between 2 and 4 carbon atoms, inclusive; X is a pharmaceutically acceptable counter-ion; and n is an integer between 1 and 10, inclusive are disclosed.