Inhibitory effects of methotrexate on spontaneous motility and Cajal-like type of tubal interstitial cells in rabbit oviduct

Oviductal Telocytes in Patients with Uterine Myoma

Tubal factor infertility occurs in 30–35% of infertile pairs and may be caused by impaired muscular contractility and ciliary beating as well as immunological imbalance and chronic inflammation. Newly discovered telocytes (TCs) have a wide palette of features, which play a role in oviduct physiology. We have observed tissue samples from human fallopian tubes in patients with and without uterine myoma by immunolabelling. According to the immunohistochemical co-expression of markers, it has been determined that TCs are engaged in a wide range of physiological processes, including local innervation, sensitivity to hypoxia, regulation of calcium, and sex steroid hormones balances. Due to the proximity of NOS- and ChAT-positive nerve fibers and the expression of ion channels markers, tubal TCs might be considered conductor cells. Additionally, their integration in contractions and cilia physiology in the context of fertility has been revealed. We have observed the difference in telocytes expression in the human oviduct between groups of patients and attempted to describe this population of cells specifically in the case of infertility development, a clinically relevant avenue for further studies.

Immunohistochemistry of Telocytes in the Uterus and Fallopian Tubes

The seminal work of Popescu and colleagues first demonstrated the existence of a new cell type - the telocytes. We were among the first who reported the presence of such cells in the female genital tract and performed TEM examinations, as well as immunohistochemical staining in the attempt to find a specific marker. Telocytes from rat and from the human uterus and from human fallopian tube were extensively investigated initially by comparison with interstitial cells of Cajal. Progress in telocyte research led to the identification of different subtypes suggestive for a heterogeneous telocyte population which can even coexist in the same location. As a consequence, the functions of TCs are still elusive and can be considered a versatile phenomenon that depends on a variety of conditions, including signal reception and transmission of information via extracellular vesicles or by direct intercellular contact.

Laparoscopic excision of coexisting left tubal and right pseudotubal pregnancy after conservative management of previous ectopic pregnancy with methotrexate: an unusual clinical entity

Tubal pregnancy concerns 97% of all ectopic pregnancies. Treatment can be either surgical (salpingostomy or salpingectomy) or medical (methotrexate administration). We present a case of a pseudotubal pregnancy after methotrexate treatment of a previous ectopic pregnancy. A37-year-old woman was diagnosed with ectopic pregnancy in the left Fallopian tube. A year ago, she had an ectopic pregnancy in the right tube, which was successfully treated with intramuscular methotrexate. During laparoscopy, two tubal masses were revealed, one in each Fallopian tube, and bilateral salpingectomy was performed. Histological analysis confirmed tubal pregnancy in the left Fallopian tube and presence of endosalpingitis in the right tube with no signs of chorionic villi. The optimal management of such cases has not yet been clarified. However, evaluation of tubal patency after a medically treated ectopic pregnancy would permit proper counsel of the patient on her fertility options, in order to choose the appropriate method of conception to achieve and accomplish a future pregnancy.

Telocytes damage in endometriosis-affected rat oviduct and potential impact on fertility

Women with endometriosis (EMs) have unexplained infertility. The recently identified telocytes (TCs) might participate in the maintenance of structural and functional integrity of oviduct tissue, but so far the involvement of TCs in EMs-affected oviduct tissue and potential impact on fertility capacity remain unknown. By an integrated technique of haematoxylin and eosin staining, in situ immunohistochemistry and double-labelled immunofluorescence staining and electron microscopy approach, TCs were studied in the autotransplantation Sprague-Dawley rat model of EMs-affected oviduct tissue and in sham control, respectively, together with determination of iNOS, COX-2, LPO and estradiol. TCs were found in perivascular connective tissue and smooth muscle bundles in sham oviduct, with typical ultrastructural features (a slender piriform/spindle/triangular cell body, and one or more extremely long prolongations, emerged from cell bodies and extend to various directions), and specific immunophenotype of CD34-positive/vimentin-positive/c-kit-negative. However, in EMs-affected oviduct tissue (grade III), extensive ultrastructural damage (degeneration, discontinue, dissolution and destruction), significant decrease or loss of TCs and interstitial fibrosis were observed, together with elevated level of iNOS, COX-2, LPO and estradiol, thus suggestive of inflammation and ischaemia-induced TCs damage. Based on TCs distribution and intercellular connections, we proposed that such damage might be involved in structural and functional abnormalities of oviduct, such as attenuated intercellular signalling and oviduct contractility, impaired immunoregulation and stem cell-mediated tissue repair, 3-D interstitial architectural derangement and tissue fibrosis. Therefore, TCs damage might provide a new explanation and potential target for EMs-induced tubal damage and fertility disorders.

Immunohistochemical alterations of cajal-like type of tubal interstitial cells in women with endometriosis and tubal ectopic pregnancy

PURPOSE

The aim of the study was to observe alterations of pacemaker cells termed cajal-like type of tubal interstitial cells (t-ICC) in oviduct from early-stage EMs and tEP, discuss underlying mechanisms and potential role in tubal factor infertility (TFI).

METHODS

Ten patients with early-stage EMs, 10 with unruptured tEP and 10 control subjects were included in this retrospective comparative study, received adnexectomy (salpingectomy) and/or hysterectomy. Paraffin-embedded full-thickness isthmic segment of oviduct specimens received immunohistochemistry with c-kit/CD117 antibody. Network distribution and area density of cells with features of t-ICC were analyzed.

RESULTS

t-ICC was detected mainly in lamina propria and smooth muscle layers. t-ICC lost its network integrity, became less densely stained, sparse and almost invisible with relatively very rare connections in EMs and tEP, apparently differing in morphology of t-ICC from control, which demonstrated rich t-ICC immunostaining and intact network. Further quantitative analysis showed the area density of t-ICC decreased significantly in early-stage EMs and tEP compared with the control (73.9 ± 8.8 vs. 156 ± 18.3 mm(2); and 76 ± 7.4 vs. 156 ± 18.3 mm(2); both P < 0.001).

CONCLUSIONS

We revealed that t-ICC underwent certain degree of cell damage, suggested that decreased expression of t-ICC network may be involved in early development of EMs and tEP, and might serve as an explanation for TFI in these patients.