Mini Bioreactor Can Support In Vitro Spermatogenesis of Mouse Testicular Tissue

Objective

It was in the early 20^th century when the quest for in vitro spermatogenesis started. In vitro spermatogenesis is critical for male cancer patients undergoing gonadotoxic treatment. Dynamic culture system creates in vivo-like conditions. In this study, it was intended to evaluate the progression of spermatogenesis after testicular tissue culture in mini-perfusion bioreactor.

Materials and Methods

In this experimental study, 12 six-day postpartum neonatal mouse testes were removed and fragmented, placed on an agarose gel in parallel to bioreactor culture, and incubated for 8 weeks. Histological, molecular and immunohistochemical evaluations were carried out after 8 weeks.

Results

Histological analysis suggested successful maintenance of spermatogenesis in tissues grown in the bioreactor but not on agarose gel, possibly because the central region did not receive sufficient oxygen and nutrients, which led to necrotic or degenerative changes. Molecular analysis indicated that Plzf, Tekt1 and Tnp1 were expressed and that their expression did not differ significantly between the bioreactor and agarose gel. Immunohistochemical evaluation of testis fragments showed that PLZF, SCP3 and ACRBP proteins were expressed in spermatogonial cells, spermatocytes and spermatozoa. PLZF expression after 8 weeks was significantly lower (P<0.05) in tissues incubated on agarose gel than in the bioreactor, but there was no significant difference between SCP3 and ACRBP expression among the bioreactor and agarose gel culture systems.

Conclusion

This three-dimensional (3D) dynamic culture system can provide somewhat similar conditions to the physiological environment of the testis. Our findings suggest that the perfusion bioreactor supports induction of spermatogenesis for generation of haploid cells. Further studies will be needed to address the fertility of the sperm generated in the bioreactor system..

Next-generation sequencing (NGS) to determine microbiome of herniated intervertebral disc

BACKGROUND CONTEXT

There is apparent causality between chronic infection of the intervertebral disc and its degenerative process. Although disc is considered a sterile tissue, collected samples of uninfected patients sent to culture testing resulted positive.

PURPOSE

The purpose of this study was to analyze the microbiome of the intervertebral disc by using and validating the next-generation sequencing (NGS) molecular test, controlled with tissue culture and clinical presentation of patients.

STUDY DESIGN/SETTING

Prospective study of consecutive patients in a hospital.

PATIENT SAMPLE

Patients with lumbar disc herniation undergoing open microdiscectomy aging 18 to 65 years.

OUTCOME MEASURES

NGS, tissue culture METHODS: Subjects undergoing open decompression surgery for lumbar disc herniation were consecutively included and clinically followed for one year. Three samples of the excised herniated disc fragment were sent to tissue culture and another sample of the disc was sent to NGS test for microbiome analysis. Control samples of the ligamentum flavum and deep muscle were collected and sent to culture.

RESULTS

A total of 17 patients were included. All patients presented negative cultures of the removed disc samples, as well as negative cultures of muscle and yellow ligament. None of the patients evolved to clinical infection one year after surgery, nor presented significant alteration of laboratory markers. NGS mapped a mean of 14,645 (range 6,540 to 27,176) DNA sequences for each disc sample of each patient. There were a total of 45 different bacteria genera remnants with different amount of DNA sequences detected. There was a mean of 8 (range 3-17) different bacterial elements in each sample of intervertebral disc. Three bacteria were present in all disc samples (Herbaspirillum, Ralstonia, and Burkolderia). Although there were a considerable mean number of bacterial sequences mapped in each disc sample, the amount of sequences related to bacteria was low. Cutibacterium acnes elements was not found in any disc microbiome analysis.

CONCLUSIONS

NGS has been proven to adequately determine bacterial DNA presence within the intervertebral disc. C. acnes was not isolated in culture neither in microbiome analysis of patients with lumbar disc herniation. We cannot confirm disc sterility since, even if it does not cause infection, there is bacterial or remnant DNA in herniated discs.

An Ex Vivo Tissue Culture Method for Discovering Cell Dynamics Involved in Stromal Vascular Fraction Vasculogenesis Using the Mouse Mesentery

Stromal vascular fraction (SVF), isolated from adipose tissue, identifies as a rich cell source comprised of endothelial cells, endothelial progenitor cells, pericytes, smooth muscle cells, fibroblasts, and immune cells. SVF represents a promising therapeutic heterogonous cell source for growing new blood microvessels due to its rich niche of cells. However, the spatiotemporal dynamics of SVF within living tissues remain largely unknown. The objective of this chapter is to describe a protocol for culturing SVF on mouse mesentery tissues in order to aid in the discovery of SVF dynamics and associated vessel growth over time. SVF was isolated from the inguinal adipose from adult mice and seeded onto mesentery tissues. Tissues were then cultured for up to 5 days and labeled with endothelial cell and pericyte markers. Representative results demonstrate the observation of SVF-derived vasculogenesis characterized by de novo vessel formation and subsequent vessel connection.

The incubot: A 3D printer-based microscope for long-term live cell imaging within a tissue culture incubator

Commercial live cell imaging systems represent a large financial burden to research groups, while current open source incubator microscopy systems lack adaptability and are sometimes inadequate for complex imaging experimentation. We present here a low-cost microscope designed for inclusion within a conventional tissue culture incubator. The build is constructed using an entry level 3D printer as the basis for the motion control system, with Raspberry Pi imaging and software integration, allowing for reflected, oblique, and fluorescence imaging of live cell monolayers. The open source nature of the design is aimed to facilitate adaptation by both the community at large and by individual researchers/groups. The development of an adaptable and easy-to-use graphic user interface (GUI) allows for the scientist to be at the core of experimental design through simple modifications of the base GUI code, or generation of an entirely purpose-built script. This adaptability will allow scientists to adapt this equipment for their experimental needs, as opposed to designing experiments to fit their current equipment. The build can be constructed for a cost of roughly €1000 and thus serves as a low-cost and adaptable addition to the open source microscopy community.

Successful Human Spermatogonial Stem Cells Homing in Recipient Mouse Testis after In Vitro Transplantation and Organ Culture

Objective

In vitro transplantation (IVT) of spermatogonial stem cells (SSCs) is one of the most recent methods in transplantation in recent decades. In this study, IVT and SSCs homing on seminiferous tubules of host testis in organ culture have been studied.

Materials and Methods

In this experimental study, human SSCs were isolated and their identities were confirmed by tracking their promyelocytic leukemia zinc finger (PLZF) protein. These cells were transplanted to adult azoospermia mouse testes using two methods, namely, IVT and in vivo transplantation as transplantation groups, and testes without transplantation of cells were assigned in the control group. Then histomorphometric, immunohistochemical and molecular studies were done after 2 weeks.

Results

After two weeks, histomorphometric studies revealed that the number of subsided spermatogonial cells (SCs) and the percentage of tubules with subsided SCs in IVT and in vivo groups were significantly more than those in the control group (P<0.05). Immunohistochemical studies in the transplantation groups confirmed that the PLZF protein was expressed in the cells subsided on the seminiferous tubule. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) demonstrated that the PLZF gene expression was only positive in the transplantation groups, but it was not significantly different between the IVT group and the in vivo group (P>0.05).

Conclusion

Testicular tissue culture conditions after SSC transplantation can help these cells subside on the seminiferous tubule basement membrane.

Effects of various glutamine concentrations on gene expression and steviol glycosides accumulation in Stevia rebaudiana Bertoni

Stevia rebaudiana Bertoni is one of the most important biologically sourced and low-calorie sweeteners that contains a lots of Steviol glycosides. Tissue culture is the best method for propagation of stevia and micro nutrients can affect both morphological traits and steviol glycosides production. In the present study, we investigated the effect of different concentrations of glutamine (10, 20, 30 and 40 g/l) on expression of UGT74G1 and UGT76G1 genes and stevioside and rebaudioside A accumulation in the leaves of stevia under in vitro conditions. The highest level of expression for UGT74G1 (1.000 Total lab unit) was seen at plants grown in MS media without glutamine and the highest gene expression level for UGT76G1 (1.321 Total lab unit) was observed at plants grown in 2% glutamine. Based on HPLC results, the highest amount of stevioside (22.74) was accumulated in plants which were under 3% glutamine treatment and the lowest production level of stevioside (16.19) was resulted under MS (0 glutamine) medium. The highest rebaudioside A (12.19) accumulation was observed under 2% glutamine treatment and the lowest accumulation of rebaudioside A (8.41) was seen at plants grown in MS medium.

Effect of KH2PO4 on gene expression, morphological and biochemical characteristics of stevia rebaudiana Bertoni under in vitro conditions

Stevia rebaudiana is one of the most important biologically sourced and low-calorie sweeteners Bertoni that has a lot of steviol glycosides. Tissue culture is the best for propagation of stevia and micro nutrients can affect both morphological traits and steviol glycosides production. Therefore, the effect of different concentrations of KH2PO4on stevia growth factors and gene expression had been studied by tissue culture methods, RT-PCR and HPLC. According the results, bud numbers had increased significantly in MS + 0.034 mMKH2PO4 media and the highest measured length was seen in plants grown under MS + 0.034 mM KH2PO4 treatment. Also, the highest growth rate (1.396 mm/d) was observed in MS + 0.034 mMKH2PO4.The best concentration of KH2PO4 for expression of UGT74G1 was 0.00425mMand the best one for UGT76G1 expression was 0.017mM. Interestingly, the best media for both stevioside and rebaudioside A accumulation was 0.017mM KH2PO4containing media. There was positive correlation between the best media for gene expression and the best one for steviol glycosides production.

Effect of salinity on gene expression, morphological and biochemical characteristics of stevia rebaudiana Bertoni under in vitro conditions

Stevia rebaudiana Bertoni is a famous medicinal plant for its low calorific value compounds which are named steviol glycosides (SGs) and they are 150-300 times sweeter than sugar. Among various SGs, stevioside and rebaudioside A considered to be the main sweetening compounds.  Soil salinity is one of the most essential stress in the world. Salinity affects the survival and yield of crops. In current study the effects of salinity and osmotic stress caused by different concentration of NaCl (0, 20, 40, 60 and 80 mM) on morphological traits, genes expressionand amount of both stevioside and rebaudioside Aunder in vitro conditions has been investigated. The morphological traits such as bud numbers, root numbers, shoot length (after 15 and 30 days) were evaluated. With increasing salinity, the values of all studied morphological traits decreased. To investigation of UGT74G1 and UGT76G1 genes expression that are involved in the synthesis of SGs, RT-PCR was done and there were significant differences between all media. The highest expression of both genes was observed in plantlets grown on MS media (with NaCl-free). Also, the lowest amounts of gene expression of the both genes were seen in MS+ 60 mM NaCl. Based on HPLC results, the highest amount of both stevioside and rebaudioside A were observed in plantlets grown in MS media (with NaCl-free). Finally, it can be concluded that stevia can survive under salt stress, but it has the best performance in the lower salinity.