In one aspect, antibodies that specifically bind to a human triggering receptor expressed on myeloid cells 2 (TREM2) protein are provided. In some embodiments, the antibody increases levels of soluble TREM2 (sTREM2). In some embodiments, the antibody decreases levels of sTREM2. In some embodiments, the antibody enhances TREM2 activity. In some embodiments, the antibody inhibits TREM2 activity.