Human testis-expressed sequence 101 is limitedly distributed in germinal epithelium of testis and disappears in seminoma

BACKGROUND: Testis-expressed sequence 101 (TEX101) was found to be highly expressed in testis and involved in acrosome reaction in previous studies. Recently, the metastasis suppressor function of TEX101 in cancer was disclosed, but the comprehensive investigation of its expression has rarely been reported. In this study, the expression features of TEX101 in normal human organs and seminoma were systematically analyzed. RESULTS: Immunohistochemistry demonstrated intense staining of TEX101 in human testis tissues; however, its expression in 27 other types of normal human organs, including the ovary, was negligible. Higher expression of TEX101 was observed in the spermatocytes and spermatids of the testis, but relatively lower staining was detected in spermatogonia. Western blotting showed a single TEX101 band of 38 kDa in human testis, but it did not correspond to the predicted molecular weight of its mature form at 21 KDa. Furthermore, we examined seminoma tissues by immunohistochemistry and found that none of the 36 samples expressed TEX101. CONCLUSIONS: Our data confirmed TEX101 to be a testis protein that could be related to the maturation process of male germ cells. The lack of TEX101 in seminoma indicated its potential role in tumor progression. This characteristic expression of TEX101 could provide a valuable reference for understanding its biological functions.

Reproductive cycle of the neotropical cichlid yellow peacock bass cichla kelberi: a novel pattern of testicular development

The present study describes the testicular maturation phases (associating the germ cells development and the morphological changes suffered by the germinal epithelium along the whole year), and the testicular morphology in the yellow peacock bass Cichla kelberi, relating it to other species. For this purpose, 78 specimens were studied according conventional techniques of light microscope. The testes in C. kelberi were classified as unrestricted spermatogonial lobular, an apomorphic characteristic in the recent groups of Teleost. Furthermore, were defined five testicular maturation phases: Preparatory phase; Early Germinal Epithelium Development; Mid Germinal Epithelium Development; Late Germinal Epithelium Development and; Regression. Similar classifications were described to other species indicating that the testicular classifications based on this propose, can be applied to lots of fishes. However, besides it similarity, the testicular reproductive cycle of C. kelberi follows a different pattern in the Regression phase, on which the gonadal restructuration and the spermatogonial proliferation gathers at the same time. So, the testes in C. kelberi never return to the Preparatory phase to start a new reproductive cycle, being this one present only at the first reproductive cycle in this species. This fact also explains the absence of individuals totally spent after their first reproductive cycle.

O presente estudo descreve as fases de maturação testicular (associando o desenvolvimento das células germinativas e as alterações morfológicas sofridas pelo epitélio germinativo ao longo do ano), e a morfologia testicular do tucunaré amarelo Cichla kelberi, relacionando a outras espécies. Com este propósito, 78 indivíduos foram estudados de acordo com técnicas convencionais para microscopia de luz. Os testículos em C. kelberi foram classificados como lobular espermatogonial irrestrito, uma característica apomórfica encontrada nos grupos recentes dos teleósteos. Além disso, cinco fases de maturação testicular foram definidas para C. kelberi: Fase Preparatória; Desenvolvimento Inicial do epitélio germinativo; Desenvolvimento Intermediário do epitélio; Desenvolvimento Final do epitélio germinativo e Regressão. Classificações similares foram descritas para outras espécies, indicando que a classificação gonadal baseada nesta proposta, pode ser aplicada a muitas espécies de peixes. Entretanto, apesar desta similaridade, o ciclo reprodutivo testicular de C. kelberi segue um padrão diferente na fase de Regressão, na qual a reestruturação gonadal e a proliferação espermatogonial ocorrem ao mesmo tempo. Deste modo, os testículos em C. kelberi nunca retornam à fase Preparatória para começar um novo ciclo reprodutivo nesta espécie. Este fato também explica a ausência de indivíduos totalmente esgotados após seu primeiro ciclo reprodutivo.

Intracytoplasmic spermatid injection and in vitro maturation: fact or fiction?

Intracytoplasmic injection with testicular spermatozoa has become a routine treatment in fertility clinics. Spermatozoa can be recovered in half of patients with nonobstructive azoospermia. The use of immature germ cells for intracytoplasmic injection has been proposed for cases in which no spermatozoa can be retrieved. However, there are low pregnancy rates following intracytoplasmic injection using round spermatids from men with no elongated spermatids or spermatozoa in their testes. The in vitro culture of immature germ cells to more mature stages has been proposed as a means to improve this poor outcome. Several years after the introduction of intracytoplasmic injection with elongating and round spermatids, uncertainty remains as to whether this approach can be considered a safe treatment option. This review outlines the clinical and scientific data regarding intracytoplasmic injection using immature germ cells and in vitro matured germ cells.

Morphological changes of Sertoli cells during the male reproductive cycle of the teleost Piaractus mesopotamicus (Holmberg, 1887)

Realizou-se uma investigação das mudanças histológicas e ultra-estruturais das células de Sertoli durante o ciclo reprodutivo de machos de Piaractus mesopotamicus. Os resultados mostraram que o desenvolvimento das células de Sertoli está estritamente relacionado à maturação das células gaméticas. Portanto, as células de Sertoli têm algum papel na maturação das células germinativas durante o ciclo reprodutivo dessa espécie, talvez formando um tecido de sustentação para os cistos espermatogênicos em desenvolvimento, ajudando a reorganização testicular para um novo ciclo reprodutivo, além de outras possíveis funções discutidas no texto.

Reproductive cycle of male matrinxa, Brycon cephalus

The matrinxa (Brycon cephalus) is an abundant and economically important fish found in the Amazon river basin in Brazil. The seasonal morphological changes in the testes of this fish were studied. Captive-bred specimens were obtained from a breeding center between March 1994 and February 1996. The testes were classified as being of the tubular, unrestricted spermatogonial type, in which four phases of germ cells (spermatogonia, spermatocytes (primary as secondary), spermatids and spermatozoa) were identified. Based on the macro, and microscopic analyses of testes, and on the gonadosomatic index, four stages of germ cell development (resting, maturation, mature and regression) were identified.

Determinación de la variabilidad en la condensación de la cromatina espermática y alfa-glucosidasa seminal con relación al espermiograma / Chromatin condensation and seminal alpha glucosidase variability and their relationship to spermiogram

Background: Sperm functional tests as an addition to semen analysis have been used to study the fertilization ability of spermatozoa. Besides the usual variability of the seminal analysis an individual variability in the results of functional tests has been recently found. Aim: to evaluate in a three months period, the individual variability of sperm parameters and sperm maturation using the chromatin condensation test and epidydime a-glucosidase (that allows to discriminate obstructive processes). Material and method: The evaluation was carried out in two donors (12 samples) apparently in good health. One of them presented evident semen analysis alterations (donor 1) and the other was considered normal under the WHO standards (donor 2). Results: The averages for donor 1 were: Sperm count 24x106 sperm/ml (range 10-58x106 sperm/ml), morphology 31.8 percent (range 30-35 percent), total motility 33 percent (range 20-42 percent), sperm maturation 38 percent (range 28-78 percent), a-glucosidase 8.65 (U/ml (range 5-10 (U/ml). The averages for donor 2 were: Sperm count 96x106 sperm/ml (range 50-140x106 sperm/ml), morphology 32.2 percent (range 30-35 percent), total motility 69 percent (range 58-78 percent), sperm maturation 17 percent (range 7-30 percent), a-glucosidase 36.9 (U/ml (range 20-82 (U/ml). Conclusions: These results show that significant variations can be found in the sperm parameters and in seminal plasma a-glucosidase; however these variations are generally maintained at the normal or abnormal ranges for each individual, except the sperm morphology that was constant and with low variation in both donors. The determination of the chromatin condensation in the semen analysis gives an additional information about the grade of sperm maturation and would be of great value for differentiating between sperm samples that show similar morphology values

Epididymal sperm maturation proteins.

Mammalian spermatozoa are not motile when they leave the testis. They have to undergo a complex maturation process to be able to fertilize in vivo. The maturation changes of mammalian sperm membrane have been extensively studied using lectins and antibodies. Some of these antigens have been purified and cloned. The interaction of secreted proteins with sperm membranes and acquisition of sperm motility as essential steps for spermatozoa to be fertile are well documented. The role of these epididymal maturation proteins in infertility and the possibility of using these antigens for immunocontraception are discussed in this review.