Table 1 Inclusion and Exclusion Criteria

Inclusion

 1. Men and women 65 years of age or older

 2. Community-dwelling

 3. Normal range of reference laboratory for: complete blood count and differential, thyroid stimulating hormone, serum vitamin B_12, folate, vitamin E, AST/SGOT and ALT/SGPT, albumin, fasting blood glucose, blood urea nitrogen and serum creatinine

 4. Negative serum tests for hepatitis B and hepatitis C

Exclusion

 1. History or clinically apparent immunologically mediated chronic conditions (e.g., rheumatoid arthritis, lupus erythematosus). No exclusion for stable chronic non-immunologically mediated conditions (e.g., osteoarthritis, well controlled hypertension)

 2. Immunodeficiency

 3. Severe respiratory disease requiring supplemental oxygen

 4. Psychiatric disorder, untreated or not in remission

 5. Infection within 2 weeks of immunization

 6. Inflammatory processes such as known chronic infections, inflammatory bowel disease or Westergren sedimentation rate (> 50 mm/hour for men, > 60 mm/hour for women)

 7. All malignancies (excluding non-melanotic skin cancer) and lymphoproliferative disorders diagnosed or treated actively during the past 5 years

 8. Arteriosclerotic event during the 2 weeks prior to enrollment (e.g., medically documented myocardial infarction, stroke, recanalization of the femoral arteries, claudication, or transient ischemic attack)

 9. Cardiac insufficiency, if heart failure present (New York Heart Association functional class III or IV)

 10. Poorly controlled hypertension (SBP ≥180 mmHg, DPB ≥100 mmHg)

 11. Renal Insufficiency (serum creatinine ≥2.0 or BUN ≥40)

 12. Elevated or low glucose (fasting ≥140 or < 70; non-fasting > 200)

 13. Cognitive impairment: score of < 23 on the Folstein Mini-Mental State Examination.

 14. Depression or mood alteration: score of ≥6 on the Geriatric Depression Scale

 15. Malnutrition as defined by clinical judgment and by decreased serum albumin (< 3.2 g/L) or hypocholesterolemia (< 160 mg/dL), or low total lymphocyte count (< 1500/ml³).

 16. Anemia (Hct < 30%) or low serum vitamin B_12, folate_, or vitamin E level

 17. History of or current alcoholism or consuming > 1 can of beer, 1 glass wine, or 1 oz. liqueur daily; current drug abuse; currently smoking ≥10 cigarettes per day.

 18. Risk factors for hepatitis B (such as parenteral drug abuse, multiple sexual partners, commercial sex worker, health care worker)

 19. History of hepatitis B infection or vaccination.

 20. Positive test for hepatitis B surface antigen or antibody, hepatitis B core antibody, or hepatitis C antibody.

 21. Unable to attend the Baltimore VA Medical Center on a regular basis; no telephone in primary residence.

 22. Subcutaneous fat pad less than 6 mm in thickness as determined by computer tomography

 23. Medication exclusions include prednisone > 5 mg/day (or equal), colchicine, methotrexate, azathioprine, cyclophosphamide, cyclosporine, or interferon.