This pilot study will first establish the feasibility of an in vivo methodology of assessing the utilization of glutamine into the TCA cycle of normal bone marrow plasma cells from healthy subjects while comparing it to an ex vivo approach

Twenty healthy adult study participants between the ages of 18 and 60 years will be recruited to participate in this pilot study that will include two groups: a) Ex Vivo group (10 volunteers) and b) In Vivo group (10 volunteers). Volunteers will be recruited to either group in a sequential alternating fashion.

In vivo 13C SIRM studies evaluating the utilization of glutamine into the TCA cycle of normal bone marrow plasma cells.

Inclusion Criteria:

• Ages 18-60
• Able to provide written consent

Exclusion Criteria:

• Renal Failure
• Pregnancy
• Active steroid use
• Active liver Disease
• Anemia (Hemoglobin < 12.5 g/dL in men and < 11.5 g/dL in women)
• H/O alcohol use (average > 2 drinks per day)
• BMI > 30