The present invention relates to pharmaceutical compositions and methods for the prevention and treatment of autoimmune diseases, infectious diseases, neurodegenerative diseases, and primary and metastatic neoplastic diseases. In the practice of the invention, the compositions are employed comprising: (a) a
heat shock protein (hsp) or an alpha(2)
macroglobulin (alpha2M); (b) a
saponin; and, optionally, (c) an antigenic molecule. The antigenic molecule displays the
antigenicity of an
antigen of: (a) a
cell that elicits an autoimmune response; (b) an agent of an infectious
disease; (c) a cancerous
cell; or (d) a
cell or structure associated with a neurodegenerative or
amyloid disease. The hsps that can be used in the practice of the invention include but are not limited to hsp70, hsp90, gp96,
calreticulin, hsp 110, grp 170, and PDI, alone or in combination with each other. The antigenic molecule can be covalently or noncovalently bound to the hsp or alpha2M, free in solution, and / or covalently bound to the
saponin. The compositions of the invention can be administered alone or in combination with the administration of
antigen presenting cells sensitized with an hsp- or alpha2M-antigenic molecule complex.