Virchows Archiv A Pathol Anat (1992) 420:213-217 Virchows ArchivA PathologicalAnatomy and Histopathology 9 Springer-Verlag 1992 Expression of adult T-ceU leukaemia-derived factor, a human thioredoxin homologue, in the human ovary throughout the menstrual cycle Toshiko Iwai 1, Shingo Fujii 3, Yoshihiko Nanbu 1, Hirofumi Nonogaki 1, Ikuo Konishi 1, Takahide Mori 1 Hiroshi Masutani 2, and Junji Yodoi 2 1 Department of Gynaecology and Obstetrics, Faculty of Medicine 2 Institute for Virus Research, Kyoto University, Kyoto, Japan 3 Department of Obstetrics and Gynaecology, School of Medicine, Shinshu University, Asahi, Matsumoto 390, Japan Received June 6, 1991 / Received after revision August 13, 1991 / Accepted August 15, 1991 Summary. An immunohistochemical study of the expres- sion of adult T-cell leukaemia-derived factor (ADF), a human thioredoxin homologue, was performed in the normal human ovary throughout the menstrual cycle. Primordial follicles were negative for ADF. Both granu- losa cells and theca interna cells at the stages of preantral and antral follicles contained ADF. The staining intensi- ty of these cells was very strong in the preovulatory dominant follicle. After ovulation, both granulo-lutein and theca-lutein cells were positive for ADF. During pregnancy, the theca-lutein cells revealed very intense ADF staining. The theca interna cells of the atretic folli- cles showed ADF staining, while the granulosa cells of such follicles did not. These results suggest that ADF localizes in the ovarian steroidogenic cells which have the binding sites of either luteinizing hormone or follicle- stimulating hormone, and that ADF expression is closely associated with the activity of the ovarian steroidogenic cells. Key words: Adult T-cell leukaemia-derived factor - Thioredoxin Human ovary - Immunohistochemistry Introduction Human T-lymphotrophic virus type 1 (HTLV-1) trans- formed T-cells hOt only express high levels of interleuk- in-2 receptors [IL-2R/p55(Tac)], but also produce an IL-2R/Tac inducer, designated adult T-cell leukae- mia(ATL)-derived factor (ADF) (Okada et al. 1985; Yo- doi et al. 1985; Tagaya et al. 1987). The human ADF protein has been purified, and we have cloned ADF cDNA (Tagaya et al. 1989). Recombinant ADF pro- duced by Escherichia coli is a multi-functional protein with many biological activities besides its IL-2R/Tac- induced activity, activities such as the promotion of lym- phocyte proliferation and synergism with IL-1 or IL-2 Offprint requests to : S. Fujii (Tagaya et al. 1989). A homology search has revealed a close relationship between ADF and a dithiol reducing enzyme, thioredoxin (Holmgren 1985; Tagaya et al. 1989). ADF is thus considered to be a human homo- logue of thioredoxin with strong dithiol-reducing activi- ty. We recently synthesized a synthetic peptide incorpor- ating the C-terminal 29mer of ADF (ADF C-peptide), and an antibody against the peptide was raised in rab- bits. Immunohistochemical study on human fetal tissues using this antibody has revealed that ADF is widely distributed in different organs and tissues during the fetal period (Fujii et al. 1991). ADF expression in fetal steroidogenic organs in particular, such as its expression in adrenal cortex, ovarian interstitial cells, and Leydig cells of the testis, prompted us to study the immunohis- tochemical localization of ADF in the steroidogenic cells of the human ovary. Moreover, it has been reported that both luteinizing hormone(LH) and follicle-stimulat- ing hormone(FSH) not only contain a sequence homolo- gous to thioredoxin (ADF) (Cys-Gly-Pro-Cys) but also have thioredoxin-like catalytic activity (Boniface and Reichert 1990). Since the ovary is a target organ of LH and FSH, we attempted to gain some new insights into the thioredoxin system during ovarian steroidogene- sis by studying ADF expression in the steroidogenic tis- sucs of the ovary throughout the menstrual cycle. Materials and methods Human ovarian specimens were obtained from 84 women, with their informed consent, at laparotomy for medical indications. The specimens were either biopsies or totally removed ovaries. The donors (32-49 years of age) had regular menstrual cycles (28 30 days) at surgery, except for 4 women who were pregnant. None of the women had received exogenous hormones for at least two cycles prior to surgery. The stage of their menstrual cycle at lapa- rotomy was determined by a combination of the following: (1) days since the onset of the last menstrual period; (2) plasma levels of LH, oestradiol and progesterone; and (3) histological examina- tion of the endometrium. Endometrial tissues were obtained either