An antibody that is capable of binding to and blocking TREM-1, comprising: (i) a heavy chain, comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:4; (ii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:5; (iii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:6; (iv) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:7; (v) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:8; (vi) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:9; (vii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:10; (viii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:14; (ix) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 11 and a light chain comprising SEQ ID NO:3; (x) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 12 and a light chain comprising SEQ ID NO:3; (xi) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 13 and a light chain comprising SEQ ID NO:3; (xii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 15 and a light chain comprising SEQ ID NO:5; or (xiii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 16 and a light chain comprising SEQ ID NO:14; wherein the heavy chain comprises an IgG4 constant region. (i) a heavy chain, comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:4; (ii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:5; (iii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:6; (iv) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:7; (v) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:8; (vi) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:9; (vii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:10; (viii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 2 and a light chain comprising SEQ ID NO:14; (ix) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 11 and a light chain comprising SEQ ID NO:3; (x) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 12 and a light chain comprising SEQ ID NO:3; (xi) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 13 and a light chain comprising SEQ ID NO:3; (xii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 15 and a light chain comprising SEQ ID NO:5; or (xiii) a heavy chain comprising the heavy chain variable region of SEQ ID NO: 16 and a light chain comprising SEQ ID NO:14;