PRIMARY: To examine the safety and potential improvement in immune responses elicited by combining rsgp120/HIV-1MN with the adjuvant QS-21. SECONDARY: To examine the role of alum in the vaccine/adjuvant formulation; to determine the optimal dose ratio of vaccine to adjuvant; and to obtain initial information on the optimal schedule of administration. AS PER AMENDMENT 07/02/97: To determine the ability of immunization with rsgp120/HV-1MN in combination with QS21 with or without alum to induce an HIV-1 envelope-specific delayed-type hypersensitivity (DTH) response in volunteers who undergo rsgp120/MN skin testing.