Sources/Clones
Accurate (KIHPL3-489D5F3, polyclonal), American Research Products (polyclonal), Biogenesis (LIP603), Chemicon (polyclonal), Dako (polyclonal), Fitzgerald (M310198, M310199, polyclonal), Seralab (polyclonal) and Zymed (polyclonal).
Fixation/Preparation
The antigen is resistant to formalin fixation and immunoreactivity is enhanced by proteolytic digestion.
Background
Human placental lactogen (hPL) is a member of an evolutionarily related gene family that includes human growth hormone (hGH) and human prolactin. hPL human chorionic gonadotropin and pregnancy-specific b 1 glycoprotein (SP1) are the three major proteins produced by the placenta. Although its expression is limited to the placenta, the physiological actions of hPL are far reaching: it has a direct somatotropic effect on fetal tissues it alters maternal carbohydrate and lipid metabolism to provide for fetal nutrient requirements and aids in the stimulation of mammary cell proliferation. Two hPL genes (hPL3 and hPL4), encoding identical proteins, are responsible for the production of up to 1 — 3 g hPL hormone/day (Walker et al, 1991; Wright et all, 1991).
Applications
Several studies have employed hPL and other placental markers for the distinction of intrauterine from extrauterine pregnancies. The presence of cytokeratin and hPL was found to be useful in identifying trophoblastic elements in endometrial curettings (Sorensen et al, 1991; Khong et al, 1994), with a sensitivity of 73% in one study (Kaspar et al, 1991). hPL can also be employed in a panel for the distinction of trophoblastic proliferations (see Appendices 1.5, 1.29, 1.30, 1.31). Complete hydatidiform mole showed strong expression of human chorionic gonadotropin (hCG) and weak expression of placental alkaline phosphatase (PLAP), whereas partial mole showed weak hCG and strong PLAP.
Choriocarcinoma, on the other hand, showed strong hCG and weak hPL and PLAP. All tissues were positive for cytokeratin but negative for vimentin (Losch & Kainz, 1996). Focal expression of hCG and diffuse expressions of hPL and PLAP was a profile not observed in complete moles (Brescia et al, 1987; Cheah & Looi, 1994). hPL has also been employed as a marker of intermediate trophoblasts although the expression of pregnancy-specific glycoprotein, cytokeratin and vimentin is a more reliable marker (Yeh et al, 1990; Shibata & Rutgers 1994).
Comments
Various tumors which show trophoblastic differentiation may express hPL (Boucher & Yoneda, 1995; Ulbright et al, 1997).
References
•Boucher LD, Yoneda K 1995 The expression of trophoblastic cell markers by lung carcinomas. Human Pathology 26: 1201-1206.
•Brescia RJ, Kurman RJ, Main CS et al 1987 Immunocytochemical localization of chorionic gonadotropin, placental lactogen, and placental alkaline phosphatase in the diagnosis of complete and partial hydatidiform moles. International Journal of Gynecological Pathology 6: 213-229.
•Cheah PL, Looi LM 1994 Expression of placental proteins in complete and partial hydatidiform moles. Pathology 26:115-118.
•Kaspar HG, To T, Dinh TV 1991 Clinical use of immunoperoxidase markers in excluding ectopic gestation. Obstetrics and Gynecology 78: 433-437.
•Khong TY, Stewart CJ, Mott C et al 1994 The usefulness of human placental lactogen and keratin immunohistochemistry in the assessment of tissue from purported intrauterine pregnancies. American Journal of Clinical Pathology 102: 72-75.
•Losch A, Kainz C 1996 Immunohistochemistry in the diagnosis of the gestational trophoblastic disease. Acta Obstetric et Gynaecologica Scandinavic 75: 753-756.
•Shibata PK, Rutgers JL 1994 The placental site nodule: an immunohistochemical study. Human Pathology 25: 1295-1301.
•Sorensen FH, Marcussen N, Daugaard HO et al 1991. Immunohistological demonstration of intermediate trophoblast in the diagnosis of uterine versus ectopic pregnancy: a retrospective survey and results of a prospective trial. British Journal of Obstetrics and Gynecology 98: 463-469.
•Ulbright TM, Young RH, Scully RE 1997 Trophoblastic tumors of the testis other than classic choriocarcinoma: ''monophasic" choriocarcinoma and placental site trophoblastic tumor: a report of two cases. American Journal of Surgical Pathology 21: 282-288.
•Wright WH, Fitzpatrick SL, Barrera-Saldana HA et al 1991 The human placental lactogen genes: structure, function, evolution and transcriptional regulation. Endocrine Reviews 12: 316-328.
•Yeh IT, O'Connor DM, Kurman RJ 1990 Intermediate trophoblast: further immunocytochemical characterization. Modern Pathology 3: 282-287.
Bibliografia
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
Accurate (KIHPL3-489D5F3, polyclonal), American Research Products (polyclonal), Biogenesis (LIP603), Chemicon (polyclonal), Dako (polyclonal), Fitzgerald (M310198, M310199, polyclonal), Seralab (polyclonal) and Zymed (polyclonal).
Fixation/Preparation
The antigen is resistant to formalin fixation and immunoreactivity is enhanced by proteolytic digestion.
Background
Human placental lactogen (hPL) is a member of an evolutionarily related gene family that includes human growth hormone (hGH) and human prolactin. hPL human chorionic gonadotropin and pregnancy-specific b 1 glycoprotein (SP1) are the three major proteins produced by the placenta. Although its expression is limited to the placenta, the physiological actions of hPL are far reaching: it has a direct somatotropic effect on fetal tissues it alters maternal carbohydrate and lipid metabolism to provide for fetal nutrient requirements and aids in the stimulation of mammary cell proliferation. Two hPL genes (hPL3 and hPL4), encoding identical proteins, are responsible for the production of up to 1 — 3 g hPL hormone/day (Walker et al, 1991; Wright et all, 1991).
Applications
Several studies have employed hPL and other placental markers for the distinction of intrauterine from extrauterine pregnancies. The presence of cytokeratin and hPL was found to be useful in identifying trophoblastic elements in endometrial curettings (Sorensen et al, 1991; Khong et al, 1994), with a sensitivity of 73% in one study (Kaspar et al, 1991). hPL can also be employed in a panel for the distinction of trophoblastic proliferations (see Appendices 1.5, 1.29, 1.30, 1.31). Complete hydatidiform mole showed strong expression of human chorionic gonadotropin (hCG) and weak expression of placental alkaline phosphatase (PLAP), whereas partial mole showed weak hCG and strong PLAP.
Choriocarcinoma, on the other hand, showed strong hCG and weak hPL and PLAP. All tissues were positive for cytokeratin but negative for vimentin (Losch & Kainz, 1996). Focal expression of hCG and diffuse expressions of hPL and PLAP was a profile not observed in complete moles (Brescia et al, 1987; Cheah & Looi, 1994). hPL has also been employed as a marker of intermediate trophoblasts although the expression of pregnancy-specific glycoprotein, cytokeratin and vimentin is a more reliable marker (Yeh et al, 1990; Shibata & Rutgers 1994).
Comments
Various tumors which show trophoblastic differentiation may express hPL (Boucher & Yoneda, 1995; Ulbright et al, 1997).
References
•Boucher LD, Yoneda K 1995 The expression of trophoblastic cell markers by lung carcinomas. Human Pathology 26: 1201-1206.
•Brescia RJ, Kurman RJ, Main CS et al 1987 Immunocytochemical localization of chorionic gonadotropin, placental lactogen, and placental alkaline phosphatase in the diagnosis of complete and partial hydatidiform moles. International Journal of Gynecological Pathology 6: 213-229.
•Cheah PL, Looi LM 1994 Expression of placental proteins in complete and partial hydatidiform moles. Pathology 26:115-118.
•Kaspar HG, To T, Dinh TV 1991 Clinical use of immunoperoxidase markers in excluding ectopic gestation. Obstetrics and Gynecology 78: 433-437.
•Khong TY, Stewart CJ, Mott C et al 1994 The usefulness of human placental lactogen and keratin immunohistochemistry in the assessment of tissue from purported intrauterine pregnancies. American Journal of Clinical Pathology 102: 72-75.
•Losch A, Kainz C 1996 Immunohistochemistry in the diagnosis of the gestational trophoblastic disease. Acta Obstetric et Gynaecologica Scandinavic 75: 753-756.
•Shibata PK, Rutgers JL 1994 The placental site nodule: an immunohistochemical study. Human Pathology 25: 1295-1301.
•Sorensen FH, Marcussen N, Daugaard HO et al 1991. Immunohistological demonstration of intermediate trophoblast in the diagnosis of uterine versus ectopic pregnancy: a retrospective survey and results of a prospective trial. British Journal of Obstetrics and Gynecology 98: 463-469.
•Ulbright TM, Young RH, Scully RE 1997 Trophoblastic tumors of the testis other than classic choriocarcinoma: ''monophasic" choriocarcinoma and placental site trophoblastic tumor: a report of two cases. American Journal of Surgical Pathology 21: 282-288.
•Wright WH, Fitzpatrick SL, Barrera-Saldana HA et al 1991 The human placental lactogen genes: structure, function, evolution and transcriptional regulation. Endocrine Reviews 12: 316-328.
•Yeh IT, O'Connor DM, Kurman RJ 1990 Intermediate trophoblast: further immunocytochemical characterization. Modern Pathology 3: 282-287.
Bibliografia
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
