Exome sequencing and functional analyses revealed CETN1 variants leads to impaired cell division and male fertility.

Human spermatogenesis requires an orchestrated expression of numerous genes in various germ cell subtypes. Therefore, the genetic landscape of male infertility is highly complex. Known genetic factors alone account for at least 15% of male infertility. However, ~40% of infertile men remain undiagnosed and are classified as idiopathic infertile men. We performed exome sequencing in 47 idiopathic infertile men (discovery cohort), followed by replication study (40 variants in 33 genes) in 844 infertile men and 709 controls using Sequenom MassARRAY® based genotyping. We report 17 variants in twelve genes that comprise both previously reported (DNAH8, DNAH17, FISP2 and SPEF2) and novel candidate genes (BRDT, CETN1, CATSPERD, GMCL1, SPATA6, TSSK4, TSKS and ZNF318) for male infertility. The latter have a strong biological nexus to human spermatogenesis and their respective mouse knockouts are concordant with human phenotypes. One candidate gene CETN1, identified in this study, was sequenced in another independent cohort of 840 infertile and 689 fertile men. Further, CETN1 variants were functionally characterized using biophysical and cell biology approaches. We demonstrate that CETN1 variant- p.Met72Thr leads to multipolar cells, fragmented nuclei during mitosis leading to cell death and show significantly perturbed ciliary disassembly dynamics. Whereas CETN1-5' UTR variant; rs367716858 leads to loss of a methylation site and increased reporter gene expression in vitro. We report a total of eight novel candidate genes identified by exome sequencing, which may have diagnostic relevance and can contribute to improved diagnostic workup and clinical management of male infertility.

TEX13B is essential for metabolic reprogramming during germ cell differentiation.

STUDY QUESTION: What is the functional significance of Tex13b in male germ cell development and differentiation? SUMMARY ANSWER: Tex13b regulates male germ cell differentiation by metabolic reprogramming during spermatogenesis. WHAT IS KNOWN ALREADY: Studies in mice and humans suggest that TEX13B is a transcription factor and is exclusively expressed in germ cells. STUDY DESIGN, SIZE, DURATION: We sequenced the coding regions of TEX13B in 628 infertile men and 427 ethnically matched fertile control men. Further, to identify the molecular function of Tex13b, we created a Tex13b knockout and conditional overexpression system in GC-1spg (hereafter, GC-1) cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: Our recent exome sequencing study identified novel candidate genes for male infertility. TEX13B was found to be one of the potential candidates, hence we explored the role of TEX13B in male infertility within a large infertile case-control cohort. We performed functional analyses of Tex13b in a GC-1 cell line using CRISPR-Cas9. We differentially labelled the cell proteins by stable isotope labelling of amino acids in cell culture (SILAC) and performed mass spectrometry-based whole-cell proteomics to identify the differential protein regulation in knockout cells compared to wild-type cells. We found that Tex13b knockout leads to downregulation of the OXPHOS complexes and upregulation of glycolysis genes, which was further validated by western blotting. These results were further confirmed by respirometry analysis in Tex13b knockout cells. Further, we also performed a conditional overexpression of TEX13B in GC-1 cells and studied the expression of OXPHOS complex proteins by western blotting. MAIN RESULTS AND THE ROLE OF CHANCE: We identified a rare variant, rs775429506 (p.Gly237Glu), exclusively in two non-obstructive-azoospermia (NOA) men, that may genetically predispose these men for infertility. Further, we demonstrated that Tex13b functions in the transcription regulation of OXPHOS complexes. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: We examined the function of Tex13b in GC-1 in vitro by knocking out and conditional overexpression, for understanding the function of Tex13b in germ cells. Unfortunately, this could not be replicated in either an animal model or in patient-derived tissue due to the non-availability of an animal model or patient's testis biopsies. WIDER IMPLICATIONS OF THE FINDINGS: This study identified that Tex13b plays an important role in male germ cell development and differentiation. The findings of this study would be useful for screening infertile males with spermatogenic failure and counselling them before the implementation of assisted reproduction technique(s). STUDY FUNDING/COMPETING INTEREST(S): Funding was provided by the Council of Scientific and Industrial Research (CSIR) under the network project (BSC0101 and MLP0113) and SERB, the Department of Science and Technology, Government of India (J C Bose Fellowship: JCB/2019/000027). The authors do not have any competing interest.

Diagnostic Yield and Safety of the 19-Gauge versus 22-Gauge Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration Needle in Subjects with Sarcoidosis (GUESS).

INTRODUCTION: Observational data suggest that the 19-gauge (G) needle for endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) offers a higher diagnostic yield than the 22-G needle in sarcoidosis. No randomized trial has compared the yield of the two needles. METHODS: We randomized consecutive subjects with suspected sarcoidosis and enlarged thoracic lymph nodes to undergo EBUS-TBNA with either the 19-G or the 22-G needle. We compared the study groups for diagnostic sensitivity (primary outcome) assessed by the yield of granulomas in subjects finally diagnosed with sarcoidosis. We also compared the sample adequacy, difficulty performing the needle puncture assessed on a visual analog scale (VAS), the subject's cough intensity on an operator-rated VAS, and procedure-related complications (secondary outcomes). RESULTS: We randomized 150 (mean age, 43.0 years; 55% women) subjects and diagnosed sarcoidosis in 116 subjects. The diagnostic sensitivity of the 19-G needle (45/60, 75.0%) was not higher (p = 0.52) than the 22-G needle (39/56, 69.6%). We obtained adequate aspirates in 90.0% and 85.7% of subjects in the respective groups (p = 0.48). The operators had greater difficulty puncturing lymph nodes with the 19-G needle (p = 0.03), while the operator-assessed cough intensity was similar in the groups (p = 0.41). Transient hypoxemia was the only complication encountered during EBUS-TBNA (two subjects in either group). CONCLUSION: We did not find the 19-G needle superior to the 22-G in diagnostic sensitivity, specimen adequacy, or safety of EBUS-TBNA in sarcoidosis. Puncturing the lymph nodes was more difficult with the 19-G needle.

Tall-columnar glandular cells in SurePath™ liquid-based cytology Pap sample: Learning from mimics/pitfalls.

We offer a comprehensive depiction of the cytomorphological characteristics of lobular endocervical glandular hyperplasia (LEGH) as observed in SurePath™ liquid-based cytology (LBC), subsequently confirmed on cone biopsy. Lobular endocervical glandular hyperplasia (LEGH), a precursor to gastric-type adenocarcinoma (GAE) of the endocervix, is rare and reports of it in cervical cytology are scarce. We provide a thorough description of the cytomorphological features of LEGH observed in SurePath™ liquid-based cytology (LBC), later confirmed by cone biopsy. To the best of our knowledge, this is the first report documenting cytology of LEGH in LBC of a Pap sample.

A sub-hepatic nodule in a young female: Chase the case.

Sertoli-Leydig cell tumours (SLCTs) are rare, mixed sex-cord stromal tumours composed of varying proportions of both Sertoli and Leydig cells, which account for <0.5% of all ovarian tumours. The cytomorphologic features of SLCTs are not well described in literature. Herein, we describe the cytomorphologic features of an SLCT at an uncommon metastatic site in a young female. Sertoli-Leydig cell tumours (SLCTs) are rare, mixed sex-cord stromal tumours composed of varying proportions of both Sertoli and Leydig cells, which account for <0.5% of all ovarian tumours. The cytomorphologic features of SLCTs are not well described in literature. Herein, we describe the cytomorphologic features of an SLCT at an uncommon metastatic site in a young female.

Bugs' eyes and black monsters: Ascitic fluid cytology in an elderly male with hematochezia.

Anorectal malignant melanomas are rare, accounting for less than 2% of all melanomas. Malignant effusions developing secondary to malignant melanoma are highly uncommon. Herein, we present the cytomorphological features of a metastatic anorectal malignant melanoma presenting with ascites at the initial clinical presentation.

High-dose (40†mg) versus low-dose (20†mg) prednisolone for treating sarcoidosis: a randomised trial (SARCORT trial).

BACKGROUND: Current guidelines recommend 20-40 mg·day-1 of oral prednisolone for treating pulmonary sarcoidosis. Whether the higher dose (40 mg·day-1) can improve outcomes remains unknown. METHODS: We conducted an investigator-initiated, single-centre, open-label, parallel-group, randomised controlled trial (ClinicalTrials.gov identifier NCT03265405). Consecutive subjects with pulmonary sarcoidosis were randomised (1:1) to receive either high-dose (40 mg·day-1 initial dose) or low-dose (20 mg·day-1 initial dose) oral prednisolone, tapered over 6 months. The primary outcome was the frequency of relapse or treatment failure at 18 months from randomisation. Key secondary outcomes included the time to relapse or treatment failure, overall response, change in forced vital capacity (FVC, in litres) at 6 and 18 months, treatment-related adverse effects and health-related quality of life (HRQoL) scores using the Sarcoidosis Health Questionnaire and Fatigue Assessment Scale. FINDINGS: We included 86 subjects (43 in each group). 42 and 43 subjects completed treatment in the high-dose and low-dose groups, respectively, while 37 (86.0%) and 41 (95.3%), respectively, completed the 18-month follow-up. 20 (46.5%) subjects had relapse or treatment failure in the high-dose group and 19 (44.2%) in the low-dose group (p=0.75). The mean time to relapse/treatment failure was similar between the groups (high-dose 307 days versus low-dose 269 days, p=0.27). The overall response, the changes in FVC at 6 and 18 months and the incidence of adverse effects were also similar. Changes in HRQoL scores did not differ between the study groups. INTERPRETATION: High-dose prednisolone was not superior to a lower dose in improving outcomes or the HRQoL in sarcoidosis and was associated with similar adverse effects.

Liquid-based cytology and immunocytochemistry in the evaluation of a vault lesion in a postmenopausal woman.

Cytological features of small cell neuroendocrine carcinoma of the cervix in a liquid-based preparation from a vault lesion.

Fine needle aspiration cytology of metastatic tumours to the thyroid.

BACKGROUND: Metastasis to the thyroid gland from non-thyroid sites is relatively rare and often poses a diagnostic difficulty on fine-needle aspiration cytology, as it often mimics primary thyroid neoplasms. METHODS: All cases of fine needle aspiration cytology (FNAC) of metastasis to the thyroid gland (2014-2022) were selected from the pathology database. The detailed cytopathological features and histopathology of the cases were studied. RESULTS: There was a total of 18 cases of secondary tumours of the thyroid. All cases had confirmed histopathological data. The most common primary tumours in our study were squamous cell carcinoma of the oesophagus (nine cases) followed by infiltrating ductal carcinoma of the breast (four cases), and one case each of renal cell carcinoma, neuroendocrine carcinoma of the lung, adenocarcinoma stomach and malignant melanoma and squamous cell carcinoma from vallecula. CONCLUSION: Metastasis to thyroid carcinoma is relatively uncommon. A history of malignancy, the presence of malignant cells amid benign thyroid follicular cells, unusual malignancy in a FNAC smear and immunocytochemistry are helpful in diagnosing such cases.

Unravelling the mysteries of Xp11.2 translocation-associated renal cell carcinoma: A case report with a review of the literature.

Cytomorphologic and immunocytochemical features of TFE3 translocation-associated renal cell carcinoma.

Cerebrospinal fluid infiltration by chronic myeloid leukaemia: Evaluation of cytomorphological features.

BACKGROUND AND AIM: To describe the cytomorphological findings of all cerebrospinal fluid (CSF) cytology samples showing infiltration by chronic myeloid leukaemia (CML) and their correlation with haematological findings. MATERIALS AND METHODS: A retrospective analysis of all CSF samples reported as showing infiltration by CML on cytology from January 2014 to December 2021 was performed. RESULTS: A total of 10 cases with positive CSF cytology were evaluated. The mean age of the patients was 34.1 years (range 17-70 years). There were more males than females. All cases were pre-diagnosed cases of CML on haematological investigations. On cytology, the smears showed atypical/immature blast-like cells, with a high nucleo-cytoplasmic ratio, opened-up chromatin, 1-2 conspicuous nucleoli and a scant to moderate amount of agranular to fine granular cytoplasm along with occasional granulocytic precursors. The shortest time interval for CSF positivity in a known case of CML was 5 months, and the longest interval was 11 years. CONCLUSION: It is extremely uncommon to encounter CML infiltration in CSF. Timely analysis of CSF cytology samples can allow quick diagnosis and alter the patient management protocol.

The utility of WhatsApp-based off-site evaluation for rapid cytology of EBUS-TBNA samples.

BACKGROUND: Whether off-site evaluation of slides by a cytologist viewing the images shared by WhatsApp improves the on-site evaluation by a pulmonologist (P-ROSE) remains unknown. This study's objective was to compare the sensitivity of P-ROSE and WHOSE for adequacy and diagnosis of cytology specimens obtained by endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA). MATERIALS AND METHODS: We retrospectively reviewed our bronchoscopy database to identify subjects who underwent EBUS-TBNA for lymph node sampling and had reports of P-ROSE and WHOSE. We collected data on the adequacy of samples as reported by the pulmonologist (P-ROSE), remotely by the cytologist (WHOSE), and finally after detailed cytologic evaluation. The study's primary outcome was to assess the increment in sensitivity for adequacy and diagnostic category (using the final cytology report as reference) by incorporating WHOSE. RESULTS: We included 264 (P-ROSE, n = 184; WHOSE, n = 80) subjects. The sensitivity (95% CI) for sample adequacy by P-ROSE and WHOSE was 65.3% (57.9%-72%) and 92% (83.6%-96.2%), respectively. There was a 26.6% (95% CI, 16%-35.2%) increment in the sensitivity for adequacy. The sensitivity (95% CI) for diagnosis by P-ROSE and WHOSE was 53.9% (46%-61.1%) and 89.8% (79.5%-95.3%), respectively. There was a 35.9% (95% CI, 23.4%-45%) increment in the sensitivity for diagnosis with WHOSE. The agreement between P-ROSE and final cytology in adequacy was poor (κ = -0.023, p = 0.616). The agreement between WHOSE and final cytology was moderate for adequacy (κ = 0.491, p = <0.001). CONCLUSION: We found WHOSE significantly improves the performance of P-ROSE for rapid assessment of cytology specimens obtained by EBUS-TBNA.

Flow cytometric immunophenotyping in a liquid-based cytology sample of pleural fluid: Connecting the dots.

Primary mediastinal large B-cell lymphoma (PMBCL) is an uncommon non-Hodgkin lymphoma that is rarely described in cytology samples. The present study highlights the importance of flowcytometric immunophenotyping and immunocytochemistry in an effusion sample of an uncommon case of PMBCL.

Cytomorphological spectrum of solitary fibrous tumour: revisited.

BACKGROUND: Solitary fibrous tumour (SFT) is a tumour of mesenchymal origin. Its diagnosis on cytology is challenging, owing to variation in cellularity, sparsely distributed cellular and stromal components. Cytomorphological findings for this type of tumour have rarely been described in the literature-only a few case reports and the occasional case series have been presented thus far. We present the cytomorphological features of SFT with special emphasis on immunochemical findings. MATERIALS AND METHODS: We present cytological data from eight cases of histopathologically proven SFTs. The cytomorphological features, immunochemical markers and differential diagnostic entities on fine needle aspiration cytology are discussed. RESULTS: Fine needle aspiration was performed at various anatomical sites. Cytology smears showed variable cellularity, with tumour cells arranged in loose clusters and as singly scattered cells. Interlacing fascicles with palisading of cells was noted. The cells were predominantly spindle to elongated, having moderate cytoplasm with elongated wavy nuclei. These nuclei had fine to coarse chromatin, with inconspicuous to prominent nucleoli. There was prominent, metachromatically staining, amorphous to fibrillary, collagenous to myxoid matrix material associated with the tumour cells. Other findings included intranuclear pseudo-inclusions, multinucleated giant cells and atypical mitoses. Cytological diagnoses offered varied from 'spindle cell neoplasm' to 'spindle cell sarcoma' or 'suggestive of sarcoma'. Immunocytochemistry (ICC) performed on cell block sections showed positivity for STAT6, CD34 and Bcl-2. CONCLUSION: Cytological diagnosis of SFT can be challenging. A careful search for characteristic cytomorphological features is diagnostically helpful. The cytomorphology should be interpreted with caution, with an appropriate ICC panel, including STAT6 and CD34.

Cervical cytology in the detection of uterine clear cell carcinoma: Diagnostic predictors from a case-control study.

INTRODUCTION: Uterine clear cell adenocarcinoma (CCC) is a rare, aggressive malignancy with poor prognosis. The present study aimed to identify and describe its characteristic morphological features in cervical cytology. METHODS: This was a 3-year retrospective case-control study. Cases included cervical samples of histopathologically proven endometrial and cervical CCC. Controls included cervical samples of histopathologically proven endometrial serous carcinoma (n = 15), endometrioid adenocarcinoma (n = 20), and endocervical adenocarcinoma (n = 15). Twenty-eight cytomorphological features were evaluated; the strength of association was determined by odds ratio (OR) and Cramer's V, and the diagnostic accuracy of statistically significant features was assessed. RESULTS: Cases consisted of histopathologically proven 25 (34.7%) endometrial and 13 (18.0%) cervical CCC. Corresponding cervical samples were available for a total of 14 (36.8%) patients, of which 13 (92.8%) were positive for epithelial cell abnormality. On univariate analysis, three cytomorphological variables were significant predictors of uterine CCC: presence of dense cytoplasm (OR = 88; V = 0.72), deep nuclear membrane irregularities (OR = 17.5; V = 0.55), and coarse chromatin (OR = 21.3; V = 0.46). Dense cytoplasm had the highest positive predictive value (92%) and high specificity (97.8%), whereas coarse chromatin had the highest sensitivity (92.3%) and negative predictive value (96.7%). CONCLUSIONS: The presence of dense cytoplasm and deep nuclear membrane irregularities in the tumour cells were strong predictors, and coarse chromatin a moderate predictor, of uterine CCC compared to its close cytological mimics.

Identifying the primary site of malignancy in carcinomatous serous effusions using immunocytochemistry.

INTRODUCTION: Malignant effusions are commonly encountered in day-to-day cytology practice. Determining the primary site of malignancy in carcinomatous effusions is a Herculean task. Cytology coupled with immunocytochemistry (ICC) is often found to be helpful in this context. MATERIALS AND METHODS: This study was conducted to evaluate the diagnostic utility of ICC on sections from cell blocks (CBs) in the detection of the primary site of origin in cases of metastatic carcinomatous effusions. To determine the origin of the primary tumour, TTF1 (lung), PAX-8 (ovary), CDX2 (colorectal), GATA3 (breast), and CK19 (pancreaticobiliary) were employed, depending on the clinical and radiological findings, and serum tumour markers. RESULTS: A total of 13,459 serous effusion samples were received for cytological evaluation from January 2017 to December 2021, of which 2708 (20.1%) were carcinomatous effusions. Out of these, 1044 (38.5%), 1611 (59.5%), and 53 (2.0%) were from pleural, peritoneal and pericardial cavities, respectively. Of these, the majority were adenocarcinoma. ICC was performed in 309 (11.4%) cases. The ovary was the most common primary site in 179 cases (57.9%), followed by the lung (75, 24.3%), pancreaticobiliary system (12, 3.9%), colon/rectum (8, 2.6%), breast (6, 1.9%), prostate (2, 0.6%) and kidney (1, 0.3). The lung was the most common primary site in pleural (67/113, 59.3%) and pericardial (6/8, 75%) effusions. The ovary (168/188, 89.4%) was the most common primary site for carcinomatous effusions in the peritoneal cavity. However, in 17 (5.5%) cases, the exact primary site could not be established. CONCLUSIONS: Judicious and methodical use of ICC on CBs helps to identify the primary site of the tumour in most carcinomatous effusions. This is of immense help to the treating clinician in directing appropriate therapy.

Metastatic germ cell tumour in effusion cytology.

BACKGROUND: Germ cell tumours infrequently metastasise to body cavities, where early detection on fluid samples is possible and can spearhead early treatment and survival. MATERIALS AND METHODS: A total of seven cases of metastatic germ cell tumours were retrieved out of 7500 effusion samples received for cytopathological examination from 2015 to 2021. Detailed cytological features of metastatic germ cell tumours in effusion samples were studied, along with a correlation between clinical, radiological, and histopathological features. RESULTS: A total of seven cases of metastatic germ cell tumours were analysed in effusion samples which included dysgerminoma (2), immature teratoma (2), yolk sac tumour (1), embryonal carcinoma (1), and mixed germ cell tumour (1). The smears showed predominantly discrete or loose clusters of cells. The cells with round nuclei and prominent nucleoli were helpful in detecting dysgerminoma and yolk sac tumours. Immature teratoma showed tiny groups of small cells and mature squamous cells. Serum tumour markers were raised in the majority of cases. CONCLUSION: Metastatic germ cell tumours in effusion are uncommon, but detailed clinical history, including serum markers and characteristic cytological features, are helpful in their diagnosis.

Sequential small cell transformation and T790M mutation in an epidermal growth factor-mutant lung adenocarcinoma: A rare occurrence with significant management implications.

BACKGROUND: Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) resistance may be acquired via genotypic and/or phenotypic transformations. Herein, we report an extremely uncommon case with sequential small cell transformation and EGFR T790M mutation, in an elderly female with EGFR exon 21 L858R-mutant lung adenocarcinoma, following treatment with a first-generation EGFR-TKI. CASE: A 67-year-old female never-smoker presented with a cough and dyspnoea of 2 months' duration. Computerised tomography revealed a 39 mm lesion in the upper lobe of the right lung with pleural effusion. Pleural fluid cytology revealed metastatic lung adenocarcinoma, and EGFR testing revealed exon 21 L858R mutation. She was started on gefitinib. After a progression-free survival of 31 months, she presented with disease progression and multiple extra-thoracic metastases. Fine needle aspiration cytology of a chest wall lesion revealed metastatic small cell carcinoma. EGFR testing on this aspirate revealed persistent L858R mutation only. In view of small cell transformation, chemotherapy (etoposide and carboplatin) was administered. After 4 months, ascitic fluid cytology revealed metastatic adenocarcinoma with persistent L858R mutation and an acquired T790M mutation (both detected on liquid biopsy as well) indicating amplification of the adenocarcinoma clone and regression of the small cell carcinoma clone. She was then initiated on osimertinib. CONCLUSIONS: The index case highlights the significance of serial EGFR genotyping along with repeated tissue and/or blood sampling in the prompt detection of genetic and phenotypic resistance mechanisms to EGFR-TKIs. Furthermore, it lends evidence in support of the upfront treatment approaches targeting the heterogeneity of acquired EGFR-TKI resistance mechanisms.

Diagnostic accuracy and cytomorphological spectrum of Wilms tumour in fine needle aspiration biopsy cytology samples supplemented with cell blocks.

OBJECTIVE: Paediatric malignant renal neoplasms are subjected to neoadjuvant chemotherapy as per Societe Internationale d'Oncologie Pediatrique; International Society of Pediatric Oncology (SIOP) protocol. An accurate tissue diagnosis is required prior to institution of chemotherapy, and hence the aim of this study was to evaluate the diagnostic accuracy of fine needle aspiration biopsy cytology (FNABC) along with cell block histology. MATERIALS AND METHODS: A retrospective audit of all paediatric renal neoplasms diagnosed by FNABC between 2015 and 2019 was performed. Histopathology correlation was done wherever available. WT cases were subjected to detailed cytomorphological evaluation. RESULTS: A total of 121 cases of paediatric renal neoplasms including 109 WT, four clear cell sarcoma, one malignant rhabdoid tumour and three mesoblastic nephroma were evaluated. The age range was 4 weeks to 8 years. FNABC samples were adequate for diagnosis in 120 of 121 cases (99.18%) and a definitive cytological diagnosis was achieved in 117 cases (96.7%). The specificity and sensitivity for a cytopathological diagnosis of WT were 98.7% and 97.4%, respectively. On detailed cytomorphological analysis of 68 histopathology-proven WT, 40 (58.8%) cases were triphasic, 23 (35.3%) were biphasic and four were composed of blastema only. The corresponding cell blocks provided additional information over the conventional smears in 23 (33.8%) cases, with epithelial or mesenchymal elements recognised and evidence of rhabdomyoblastic differentiation. CONCLUSION: FNABC along with cell block histology is highly accurate for diagnosis of WT and other malignant paediatric renal neoplasms and is recommended as the technique of choice in centres with cytopathology expertise for establishing a cellular diagnosis prior to commencement of neoadjuvant chemotherapy.

Corneal reconstruction in chemically damaged cornea using temperature responsive surface assisted mesenchymal stem cell transplantation in rabbits.

PURPOSE: Transplantation of autologous stem cells over damaged cornea seems to be a promising approach for corneal reconstruction. Use of a biocompatible carrier is still a challenge in bedside translation of transplantation. We investigated corneal reconstruction and tissue remodelling by transplantation of mesenchymal stem cells (MSCs) using temperature responsive membranes in chemically damaged rabbit cornea model. METHODS: MSCs were cultured from rabbit's bone marrow and transplanted over alkali injured cornea, using either temperature responsive membrane or fibrin glue method. Endogenous levels of MSCs were assessed to decide the optimal time point for transplanting cells. MSC transplanted corneas were harvested at different time points post-transplantation. Corneal repair markers were evaluated using histopathology, immunohistochemistry (IHC) and real time qPCR. The quality of cornea reconstructed was evaluated and compared using corneal opacity scoring and immunohistochemistry (IHC). RESULTS: Use of temperature responsive surface as carrier resulted in uniform and homogenous delivery of MSCs sheet over the damaged corneal surface. Corneal transparency improved day 7 onwards post-MSC transplantation in rabbit chemically injured cornea. Complete re-epithelialization of injured cornea was observed 15 days after MSC transplantation. Restoration of vimentin, α-smooth muscle actin and collagen levels in MSC transplanted cornea was observed post-transplantation. Further, differentiation of MSCs into mature corneal epithelial cells was also observed upon transplantation. CONCLUSIONS: The extent of corneal repair was apparently better using temperature responsive surfaces. The surface provides biocompatible niche for MSCs and can be a method of choice in clinics for cell transplantation over the damaged ocular surfaces.