Sources/Clones
Axcel/Accurate (MP57), Biogenesis (AHN-10), Calbiochem (polyclonal), Chemicon (AHN10), Dako (NP57).
Fixation/Preparation
NP57 may be used on both formalin-fixed, paraffin-embedded sections and frozen sections. If other fixatives are used, e.g. acetone or methanol, there is a tendency for the antigen to diffuse from the myeloid cell cytoplasm and to localize in the cell nucleus.
Background
Neutrophil elastase is a neutral protease which plays a major role in the killing of microorganisms and the initiation of tissue injury during inflammatory reactions. The enzyme is present in the primary (azurophilic) granules of myeloid cells (Baggiolini et al, 1978). Neutrophil elastase consists of three isoenzymes with similar molecular masses (approximately 30 kD) (Ohlsson & Olsson, 1974). Monoclonal antineutrophil elastase (NP57) was raised against human neutrophil granule proteins (Pulford et al, 1988). This antibody labels neutrophils in routinely processed histological specimens and also reacts (although more weakly) with a minor population of normal blood monocytes. Other cell types, including epithelial cells, are NP57 negative (Pulford et al, 1988).
Applications
Neoplastic cells in 27/37 (73%) bone marrow specimens of acute myeloid leukemia were NP57 + (Ralfkiaer et al, 1989). The number of positive cells varied from few (5-10%) to virtually all of the cells. In routinely processed biopsy specimens from lymphoid organs with extramedullary hematopoiesis or infiltrates of chronic myeloid leukemia, NP57 was confined to neutrophils and their precursors (Ralfkiaer et al, 1989). Other studies (Van Der Schoot et al, 1990; Traweek et al, 1993) have demonstrated NP57 positivity in 53% of acute myeloid leukemia and 54% of extramedullary myeloid cell tumors respectively. These percentages appear to be slightly lower than that obtained when staining for myeloperoxidase. This probably indicates that elastase is synthesized later during myeloid maturation than myeloperoxidase. Leukemias of lymphoid origin are not stained.
Comments
The above results indicate that detection of elastase with monoclonal NP57 forms a useful supplement to other immunohistochemical markers for myeloid disorders e.g. myeloperoxidase, lysozyme, CD43 and CD15.
References
•Baggiolini M, Bretz U, Dewald B, Feigenson ME 1978. The polymorphonuclear leukocyte. Agents and Actions 8: 3-10.
•Ohlsson K, Olsson I 1974. The neutral proteases of human granulocytes. Isolation and partial characterization of granulocyte elastases. European Journal of Biochemistry 42: 519-527.
•Pulford KAF, Erber WN, Crick JA, Olsson I, Gatter KC, Mason DY 1988. Monoclonal antibody against human neutrophil elastase for the study of normal and leukaemic myeloid cells. Journal of Clinical Pathology 41: 853-860.
•Ralfiaier E, Pulford KAF, Lauritzen AF, Armstrom S, Guldhammer B, Mason DY 1989. Diagnosis of acute myeloid leukaemia with the use of monoclonal anti-neutrophil elastase (NP-57) reactive with routinely processed biopsy samples. Histopathology 14: 637-643. acute myeloid leukaemia with the use of monoclonal anti-neutrophil elastase (NP-57) reactive with routinely processed biopsy samples. Histopathology 14: 637-643.
•Traweek ST, Arber DA, Rappaport H, Brynes RK 1993. Extramedullary myeloid cell tumors: an immunohistochemical and morphologic study of 28 cases. American Journal of Surgical Pathology 17: 1011-1019.
•Van Der Schoot CE, Daams GM, Pinkster J, Vet R, Von Dem Borne AEG 1990. Monoclonal antibodies against myeloperoxidase are valuable immunological reagents for the diagnosis of acute myeloid leukaemia. British Journal of Haematology 74: 173-178.
Bibliografia
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
Axcel/Accurate (MP57), Biogenesis (AHN-10), Calbiochem (polyclonal), Chemicon (AHN10), Dako (NP57).
Fixation/Preparation
NP57 may be used on both formalin-fixed, paraffin-embedded sections and frozen sections. If other fixatives are used, e.g. acetone or methanol, there is a tendency for the antigen to diffuse from the myeloid cell cytoplasm and to localize in the cell nucleus.
Background
Neutrophil elastase is a neutral protease which plays a major role in the killing of microorganisms and the initiation of tissue injury during inflammatory reactions. The enzyme is present in the primary (azurophilic) granules of myeloid cells (Baggiolini et al, 1978). Neutrophil elastase consists of three isoenzymes with similar molecular masses (approximately 30 kD) (Ohlsson & Olsson, 1974). Monoclonal antineutrophil elastase (NP57) was raised against human neutrophil granule proteins (Pulford et al, 1988). This antibody labels neutrophils in routinely processed histological specimens and also reacts (although more weakly) with a minor population of normal blood monocytes. Other cell types, including epithelial cells, are NP57 negative (Pulford et al, 1988).
Applications
Neoplastic cells in 27/37 (73%) bone marrow specimens of acute myeloid leukemia were NP57 + (Ralfkiaer et al, 1989). The number of positive cells varied from few (5-10%) to virtually all of the cells. In routinely processed biopsy specimens from lymphoid organs with extramedullary hematopoiesis or infiltrates of chronic myeloid leukemia, NP57 was confined to neutrophils and their precursors (Ralfkiaer et al, 1989). Other studies (Van Der Schoot et al, 1990; Traweek et al, 1993) have demonstrated NP57 positivity in 53% of acute myeloid leukemia and 54% of extramedullary myeloid cell tumors respectively. These percentages appear to be slightly lower than that obtained when staining for myeloperoxidase. This probably indicates that elastase is synthesized later during myeloid maturation than myeloperoxidase. Leukemias of lymphoid origin are not stained.
Comments
The above results indicate that detection of elastase with monoclonal NP57 forms a useful supplement to other immunohistochemical markers for myeloid disorders e.g. myeloperoxidase, lysozyme, CD43 and CD15.
References
•Baggiolini M, Bretz U, Dewald B, Feigenson ME 1978. The polymorphonuclear leukocyte. Agents and Actions 8: 3-10.
•Ohlsson K, Olsson I 1974. The neutral proteases of human granulocytes. Isolation and partial characterization of granulocyte elastases. European Journal of Biochemistry 42: 519-527.
•Pulford KAF, Erber WN, Crick JA, Olsson I, Gatter KC, Mason DY 1988. Monoclonal antibody against human neutrophil elastase for the study of normal and leukaemic myeloid cells. Journal of Clinical Pathology 41: 853-860.
•Ralfiaier E, Pulford KAF, Lauritzen AF, Armstrom S, Guldhammer B, Mason DY 1989. Diagnosis of acute myeloid leukaemia with the use of monoclonal anti-neutrophil elastase (NP-57) reactive with routinely processed biopsy samples. Histopathology 14: 637-643. acute myeloid leukaemia with the use of monoclonal anti-neutrophil elastase (NP-57) reactive with routinely processed biopsy samples. Histopathology 14: 637-643.
•Traweek ST, Arber DA, Rappaport H, Brynes RK 1993. Extramedullary myeloid cell tumors: an immunohistochemical and morphologic study of 28 cases. American Journal of Surgical Pathology 17: 1011-1019.
•Van Der Schoot CE, Daams GM, Pinkster J, Vet R, Von Dem Borne AEG 1990. Monoclonal antibodies against myeloperoxidase are valuable immunological reagents for the diagnosis of acute myeloid leukaemia. British Journal of Haematology 74: 173-178.
Bibliografia
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
