The rationale for the study is to determine if Campath-1H can be used in patients recently diagnosed with type I DM, to induce a state of immunological unresponsiveness such that subjects can safely preserve beta cell mass and eliminate or lower insulin requirements, preserving excellent metabolic control.

Inclusion Criteria:

• Adult subjects ages 18-35, with new onset type 1 diabetes mellitus (within 2-12 weeks of diagnosis), one or more islet autoantibody to GAD, IA2, IAA or islet cell cytoplasmic antibody (ICA) within 2 weeks of diabetes diagnosis.

Exclusion Criteria:

• Subjects under 18 years of age or over 35 years of age.
• Subjects who have previously received an organ transplant.
• Subjects who are currently receiving systemic corticosteroids for other medical diseases in which the physician feels discontinuation of corticosteroids is contraindicated.
• Subjects with a history of other medical condition(s) known to affect blood glucose values (i.e., Cushing's disease, acromegaly).
• Subjects with a history of other chronic systemic inflammatory or autoimmune disease or other severe medical condition. (A history of treated hypothyroidism with documentation of normal serum thyroid hormone levels will not be exclusionary.)
• Patients with a history of hepatitis B, hepatitis C, or HIV.
• PPD positive at the time of evaluation.
• Thrombocytopenia or neutropenia. Individuals will be considered to have thrombocytopenia if they have a platelet count <100,000 platelets/mm2 or <3,000 WBC/ml.
• Subjects with a history of renal, pulmonary, or cardiac failure
• Subjects with severe systemic infections. Only those subjects who have completed treatment and have shown a complete clinical resolution will be considered eligible for the study.