Inclusion Criteria

Patients must be:

• Normal, healthy, HIV-negative adults who fully comprehend the purpose and details of the study.
• Available for 2 years of follow-up.

Exclusion Criteria

Co-existing Condition:

Patients with the following conditions or symptoms are excluded:

• History of positive PPD (tuberculin test) and abnormal chest x-ray.
• Positive syphilis serology (e.g., RPR).
• Positive for circulating hepatitis B surface antigen.

Patients with the following are excluded:

• They or their sexual partners have identifiable high-risk behavior for HIV infection.
• History of immunodeficiency or chronic illness.
• Evidence of psychological or psychiatric problems that may lead to noncompliance.

Prior Medication:

Excluded:

• Immunosuppressive medications.

Prior Treatment:

Excluded:

• Blood transfusions or cryoprecipitates within the past 6 months.