Testicular tissue cryopreservation: 8 years of experience from a coordinated network of academic centers

STUDY QUESTION

Is it feasible to disseminate testicular tissue cryopreservation with a standardized protocol through a coordinated network of centers and provide centralized processing/freezing for centers that do not have those capabilities?

SUMMARY ANSWER

Centralized processing and freezing of testicular tissue from multiple sites is feasible and accelerates recruitment, providing the statistical power to make inferences that may inform fertility preservation practice.

WHAT IS KNOWN ALREADY

Several centers in the USA and abroad are preserving testicular biopsies for patients who cannot preserve sperm in anticipation that cell- or tissue-based therapies can be used in the future to generate sperm and offspring.

STUDY DESIGN, SIZE, DURATION

Testicular tissue samples from 189 patients were cryopreserved between January 2011 and November 2018. Medical diagnosis, previous chemotherapy exposure, tissue weight, and presence of germ cells were recorded.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Human testicular tissue samples were obtained from patients undergoing treatments likely to cause infertility. Twenty five percent of the patient's tissue was donated to research and 75% was stored for patient's future use. The tissue was weighed, and research tissue was fixed for histological analysis with Periodic acid-Schiff hematoxylin staining and/or immunofluorescence staining for DEAD-box helicase 4, and/or undifferentiated embryonic cell transcription factor 1.

MAIN RESULTS AND THE ROLE OF CHANCE

The average age of fertility preservation patients was 7.9 (SD = 5) years and ranged from 5 months to 34 years. The average amount of tissue collected was 411.3 (SD = 837.3) mg and ranged from 14.4 mg-6880.2 mg. Malignancies (n = 118) were the most common indication for testicular tissue freezing, followed by blood disorders (n = 45) and other conditions (n = 26). Thirty nine percent (n = 74) of patients had initiated their chemotherapy prior to undergoing testicular biopsy. Of the 189 patients recruited to date, 137 have been analyzed for the presence of germ cells and germ cells were confirmed in 132.

LIMITATIONS, REASONS FOR CAUTION

This is a descriptive study of testicular tissues obtained from patients who were at risk of infertility. The function of spermatogonia in those biopsies could not be tested by transplantation due limited sample size.

WIDER IMPLICATIONS OF THE FINDINGS

Patients and/or guardians are willing to pursue an experimental fertility preservation procedure when no alternatives are available. Our coordinated network of centers found that many patients request fertility preservation after initiating gonadotoxic therapies. This study demonstrates that undifferentiated stem and progenitor spermatogonia may be recovered from the testicular tissues of patients who are in the early stages of their treatment and have not yet received an ablative dose of therapy. The function of those spermatogonia was not tested.

STUDY FUNDING/COMPETING INTEREST(S)

Support for the research was from the Eunice Kennedy Shriver National Institute for Child Health and Human Development grants HD061289 and HD092084, the Scaife Foundation, the Richard King Mellon Foundation, the Departments of Ob/Gyn & Reproductive Sciences and Urology of the University of Pittsburgh Medical Center, United States-Israel Binational Science Foundation (BSF), and the Kahn Foundation. The authors declare that they do not have competing financial interests.

Human primary macrophages scavenge AuNPs and eliminate it through exosomes. A natural shuttling for nanomaterials

The use of nanomaterials is increasing but the real risk associated with their use in humans has to be defined. In fact, nanomaterials tend to accumulate in organs over a long period of time and are slowly degraded or eliminated by the body. Exosomes are nanovesicles actively shuttle molecules, including chemical products and metals, through the body. Macrophages scavenge the body from both organic and inorganic substances, and they use to release high amounts of exosomes. We hypothesized that macrophages may have a role in eliminating nanomaterials through their exosomes. We treated human primary macrophages with 20 nm gold nanoparticles (AuNPs), analyzing the presence of AuNPs in both cells and the released exosomes by the implementation of different techniques, including SP-ICP-MS and NTA. We showed that macrophages endocytosed AuNPs and released them through exosomes. Our study on one hand provide the evidence for a new methodology in the early identification of the nanomaterials levels in exposed subjects. On the other hand we depict a way our body shuttle virtually intact nanoparticles through macrophage-released exosomes.

Abstract P6-14-07: Not presented

This abstract was not presented at the conference.

Citation Format: Lai J, Antill Y, Richardson G, Vereker M, David S. Not presented [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-14-07.

Chemical strategies to unravel bacterial-eukaryotic signaling

The common language of bacteria and higher life forms is a lexicon of small molecules that the research community is only beginning to decipher. While many new signaling molecules have been discovered in recent years, the identification of their targets is mostly lagging. This review will focus on the latest chemical-probe based research aimed at understanding how bacteria interact chemically with mammals and plants. In general, chemical biology strategies remain under-utilized in this complex field of research, with a few key exceptions, and we hope that this review encourages others to implement these techniques in their research. Specifically, we highlight the chemical biology techniques used in recent studies, especially activity-based protein profiling, that have been applied to unravel the chemical mechanisms of interkingdom interactions.

Low genomic diversity of Legionella pneumophila within clinical specimens

Objectives

Legionella pneumophila is the leading cause of Legionnaires' disease, a severe form of pneumonia acquired from environmental sources. Investigations of both sporadic cases and outbreaks rely mostly on analysis of a single to a few colony pick(s) isolated from each patient. However, because of the lack of data describing diversity within single patients, the optimal number of picks is unknown. Here, we investigated diversity within individual patients using sequence-based typing (SBT) and whole-genome sequencing (WGS).

Methods

Ten isolates of L. pneumophila were obtained from each of ten epidemiologically unrelated patients. SBT and WGS were undertaken, and single-nucleotide polymorphisms (SNPs) were identified between isolates from the same patient.

Results

The same sequence type (ST) was obtained for each set of ten isolates. Using genomic analysis, zero SNPs were identified between isolates from seven patients, a maximum of one SNP was found between isolates from two patients, and a maximum of two SNPs was found amongst isolates from one patient. Assuming that the full within-host diversity has been captured with ten isolates, statistical analyses showed that, on average, analysis of one isolate would yield a 70% chance of capturing all observed genotypes, and seven isolates would yield a 90% chance.

Conclusions

SBT and WGS analyses of multiple colony picks obtained from ten patients showed no, or very low, within-host genomic diversity in L. pneumophila, suggesting that analysis of one colony pick per patient will often be sufficient to obtain reliable typing data to aid investigation of cases of Legionnaires' disease.

In Vitro and in Vivo Biocompatibility of Substituted Cellulose and Synthetic Membranes

Regenerated cellulosic membranes are held as bioincompatible due to their high complement - and leukopenia - inducing properties. Adherence of polymorphonuclear neutrophils and monocyte purified from normal human blood to the three membranes were evaluated in an in vitro recirculation circuit in the presence or absence of fresh, autologous plasma after recirculation in an in vitro circuit using minimodules with each of the three membranes. In in vivo studies, 9 patients were treated with conventional haemodialysis for 2 weeks with each membrane and 1 week for wash-out using haemodialysers with the following surface: 1.95 m2 for benzyl-cellulose, 1.8 m2 for acetate-cellulose and low-flux polysulfone. Measurement of leukopenia, plasma C3a des Arg and elastase-α 1 proteinase inhibitor complex levels as well as urea, creatinine, phosphate and uric acid clearances was performed. Plasma-free neutrophils adhered maximally to acetate-cellulose (65% remaining in the circulation), while there was no significant difference between low-flux polysulfone and benzyl-cellulose (80% circulating neutrophils, at 15 min, p<0.001 vs acetate cellulose). In the presence of fresh plasma, as source of complement, the differences between acetate cellulose vs polysulfone and benzyl-cellulose were even more evident, suggesting the role of complement-activated products in neutrophil adherence. A similar trend was observed for monocyte adherence with the three membranes in the absence or presence of plasma. In vivo studies showed that the nadir of leukopenia was at 15 and 30 min with acetate-cellulose (79%) and benzyl-cellulose (50%) (p<0.05 acetate- vs benzyl-cellulose) and at 15 min with polysulfone (24%) (p<0.01 vs acetate- and benzyl-cellulose). Plasma C3a des Arg levels arose to 2037 ± 120 ng/ml, 1216 + 434 ng/ml and 46 ± 55 ng/ml with acetate-, benzyl-cellulose and polysulfone, respectively. No pre- vs post-dialysis increase in the intracellular content of TNF-α was detected with any of three membranes. Clearance values of urea, creatinine and uric acid were superimposable for all the three membranes. However, benzyl cellulose had a significantly higher clearance for phosphorus (normalized for surface area) (p<0.01 vs acetate-cellulose, 0.001 vs polysulfone). These results implicate that synthetic modification of the cellulose polymer as for the benzyl-cellulose significantly reduces the in vitro adherence, delays the in vivo activation of “classic” biocompatibility parameters and notably improves the removal of inorganic phosphorus.

Predilution Hemofiltration. Clinical Experience and Removal of Small Molecular Weight Solutes

Over 1500 treatments of hemofiltration with on-line preparation of substitution fluid were performed in 16 patients. Two patients were treated for over 40 months. On-line preparation of the solution allowed use of bicarbonate as a buffer. 73-74 L/session were infused in pre-dilution modality, at a rate of about 370 ml/min, and the treatment length was above 4 hrs. The good quality of on-line prepared solution was confirmed by the negativity of microbiological tests and by the absence of clinical or sub-clinical reactions in patients. Urea clearance was calculated by equations considering either plasma flow or whole blood flow. Results were 196-197 ml/min and 186-183 ml/min, respectively. The latter was nearer to the value of directly measured clearance (182-173 ml/min). Kt/V urea was about 1 per session and PCR ranged between 1.3 and 1.4 g/kg/day. A high vascular stability was also observed. Since sodium balance may, at least in part, account for better vascular stability, sodium sieving coefficient was measured during the treatment. The sodium-retaining effect of the increase of protein concentration within the filter, due to the ultrafiltration, was less relevant in pre-dilution hemofiltration if compared to post-dilution hemofiltration. It has been calculated that to obtain a sodium balance similar to that of the hemodialysis (HD), the sodium concentration of infusion solution should be about 2 mEq/L higher than HD dialysis solution. However, difficulty in performing accurate balance studies prevents a general agreement on these conclusions.

Colorectal cancer and inflammatory bowel diseases: effects of diet and antioxidants

It is well established that oxidative stress is common in inflammatory bowel diseases (IBDs). Accordingly, antioxidants are recommended for treatment. The aim of this study is to compare the effects of antioxidants contained in the various types of tea on symptoms and evolution of IBD and colorectal cancer (CRC). Analysis of the literature revealed that the theaflavin-3, 30-digallate (TFDG) contained in black tea, and epigallocatechin-3-O-gallate (EGCG) contained in green tea have protective effects against oxidative stress. Moreover, these substances are involved in many biochemical processes responsible for inflammation and proliferation of cancer cells. It is documented that both TFDG and EGCG are able to reduce inflammatory phenomena and symptoms associated with IBD, as well as to reduce the proliferation of CRC cells. Most studies are performed in vitro or in experimental animal models. It is, therefore, advisable to formulate studies that could be carried out on humans or human samples, in order to develop the appropriate therapeutic strategies.

Colorectal cancer: an update on the effects of lycopene on tumor progression and cell proliferation

Colorectal cancer (CRC) is one of the most common cancers worldwide. Various factors, including oxidative stress, where excessive productions of reactive oxygen species (ROS) and reactive nitrogen species (RNS) occur, contribute to its pathogenesis. Numerous studies have investigated the effect of antioxidant substances derived from food such as fruits and vegetables; however, data on Lycopene are still rare. Studies on HT-29 colorectal cancer cells and on animal models have shown that lycopene has effects on cell proliferation and on the progression of the CRC by interacting with various cellular signaling pathways. This analysis of the literature focused on the antioxidant effect of lycopene, a substance that is found in the tomato.

Use of core biopsy in diagnosing cervical lymphadenopathy: a viable alternative to surgical excisional biopsy of lymph nodes?

OBJECTIVES Lymphoma often presents with a neck mass and while fine-needle aspiration cytology may be suggestive, tissue biopsy is required for reliable diagnosis and classification of a lymphoma that is sufficient to deliver the correct treatment for the patient. Traditionally, excisional biopsy of a lymph node has been the standard method of tissue sampling, providing ample tissue for assessment. However, this requires theatre time, and preceding fine-needle aspiration cytology, which may incur a delay. With careful use of tissue, coupled with advances in immunohistochemical and molecular investigative techniques, core biopsy provides a possible alternative to traditional fine-needle aspiration and excisional biopsy. In this study, we aimed to determine the efficacy of diagnosing neck masses. METHOD A retrospective analysis was performed of patients being investigated for a neck mass who were undergoing ultrasound-guided core biopsies of cervical lymph nodes over a 17-month period. The final histology report was scrutinised to assess whether adequate tissue was obtained to allow for full tissue diagnosis. RESULTS Over the 17-month period analysed, 70 patients with cervical lymphadenopathy underwent core biopsy. Of these, 63 (90%) were diagnostic for either lymphoma or other pathology and did not require further tissue sampling. Overall, 19 patients were diagnosed with lymphoma, of which only 1 required further biopsy due to inconclusive initial core biopsy. CONCLUSIONS Current guidelines for investigating lymphomas require that excisional biopsy be performed to obtain ample tissue to allow full nodal architecture assessment and ancillary investigation to reach an accurate histological classification. Within our head and neck multidisciplinary team, however, it is considered that results from core biopsies can be obtained in a more timely fashion and with histological accuracy equal to those of open biopsy. The results obtained demonstrate that core biopsy is an effective tool for investigation. We believe this should be the first-line investigation of choice, as it reduces the need for patients to undergo surgery, is more cost effective and offers a faster diagnosis.