Chimeric cell-targeting pathogenic organism and method of therapeutic use

A chimeric pathogenic C. albicans comprising:

• an integrin1 (INT1) fusion protein in which the I domain is replaced by an antibody fragment that binds to a disease-associated antigen on a diseased cell,
• a disabled wild-type high affininity iron transporter (CAFTR) gene, and
• a DNA construct comprising a wild-type CAFTR gene under the control of an enhanced filamentous growth protein (EFG1p) response element, wherein binding of the antibody to the disease-associated antigen triggers expression of the CAFTR gene in the DNA construct and filamentous transformation in the chimeric pathogenic C albicans.

A method for generating a chimeric therapeutic organism from a pathogenic organism that possesses in the wild-type an integrin-like protein with an I domain, said method comprising:

• replacing the I domain in the integrin-like protein of the pathogenic organism with an antibody fragment that binds to a disease-associated antigen on a diseased cell;
• wherein the wild-type pathogenic organism undergoes virulent transformation by binding of the I domain of the surface integrin-like protein to a cell, and wherein the chimeric therapeutic organism undergoes virulent transformation by binding of the antibody fragment to the disease-associated antigen on the cell.