Improved Methods of Cell Selection for Bone Marrow Transplant Alternatives

* INCLUSION CRITERIA: * Healthy individual aged 18 to 60 years. * No active infection or history of recurrent infection. * Normal renal function: creatinine \<1.5 mg/dL or estimated glomerular filtration rate (eGFR) \>=60 mL/min/1.73 m\^2, with no significant proteinuria. Normal liver function: bilirubin \<2.0 mg/dL (when unconjugated), transaminases \<2.0x ULN in the absence of known liver disease. Normal blood count: WBC 2,500-11,000/microliter, ANC \>1,500/microliter, platelets \>150,000/microliter, hemoglobin \>12.0 g/dL. * Normal cardiovascular function, no history of chest pain, myocardial infarction, peripheral vascular disease, transient ischemic attack, or stroke. * Healthy female subjects of childbearing age should have a negative serum pregnancy test with one week of beginning G-CSF administration. * Female subjects should not be lactating. * Subject must be eligible for normal blood donation. He or she must be tested negative for syphilis (RPR), hepatitis B and C (HBsAg, Anti-HBc, Anti-HCV), HIV, HTLV-1, West Nile virus, T. Cruzi and Babesia test. * Subject must be able to comprehend the investigational nature of the study and provide informed consent to participate in the protocol. * Antecubital veins must be adequate for peripheral access during apheresis. Potential participants must be screened by an apheresis nurse to check venous access before protocol entry. EXCLUSION CRITERIA: * Active viral, bacterial, fungal or parasite infection. * Female with positive pregnancy test or lactating. * Active or moderate-to-severe autoimmune disease that is currently treated or expected to require immunosuppressive therapy. Candidates with stable, well-controlled mild autoimmune disease may be considered on a case-by-case basis. * Active or recent malignancy within the past 5 years. Individuals with remote (\>5 years) histories of low-risk malignancies in remission (e.g., localized prostate cancer) or treated basal cell carcinoma may be included. * History of any hematologic disorders. * History of clinically significant cardiovascular disease (e.g., symptomatic coronary artery disease, uncontrolled hypertension). Minor risk factors must be evaluated on a case-by-case basis (e.g., controlled hypertension). * Any positive serum screening test as listed in eligibility. * Allergy to G-CSF or bacterial E coli products. * Administration of NSAID within. 5-7 days of starting the protocol, depending on drug half-life. * History of G-CSF administration and leukapheresis within past 3 months.