Patients with rare autoimmune inflammatory disorders demonstrate sub-clinical left ventricular dysfunction

Background

ANCA-associated Vasculitis (AAV) and inflammatory myositis (IM) are rare inflammatory autoimmune disorders mediated via pro-inflammatory cytokines and result in a systemic inflammatory state with multi-organ involvement. There is growing evidence to suggest cardiovascular involvement within these inflammatory states. Left ventricular global longitudinal strain (LV-GLS) is proposed to be a more sensitive measure of LV systolic function when compared to standard two-dimensional measures such as LV ejection fraction (LVEF).

Purpose

The purpose of this study was to assess for subclinical cardiac dysfunction in these cohorts when compared to controls.

Methods

Consecutive patients with AAV (n=56) and IM (n=68) admitted to our institution during 2013–2021 were assessed. Patients with pre-existing cardiovascular disease, significant renal impairment (eGFR <30mL/min/1.73m2), LVEF <50% or lack of comprehensive transthoracic echocardiography during admission were excluded (n=72). LV-GLS was measured offline using vendor-independent software (TomTec Arena, Germany v4.6).

Results

A total of 52 patients (22 AAV and 30 IM) were age- and gender-matched to 52 controls. In comparison of the two study populations (AAV and IM), patients with AAV had higher rates of renal impairment (p=0.02) but lower rates of interstitial lung disease when compared to IM (p=0.02). There were no differences between the two groups in terms of cardiovascular risk factors, demographics or other laboratory investigations (p>0.05 for all). In comparison to the control population, patients with AAV and IM had higher indexed LV mass and a lower TAPSE, respectively, when compared to controls. These cohorts also demonstrated impaired LV-GLS (−17.7±2.6 vs −20.6±2.4; p<0.01) when compared to healthy controls, despite no differences in LVEF (62.6±7.8 vs 61.8±5.4; p=0.56) between both groups.

Conclusions

Our results suggest that patients with autoimmune inflammatory disorders demonstrate subclinical LV dysfunction which is likely secondary to a chronic inflammatory state.

Funding Acknowledgement

Type of funding sources: None.

Post-transcriptional and translational control of the morphology and virulence in human fungal pathogens

Host-pathogen interactions at the molecular level are the key to fungal pathogenesis. Fungal pathogens utilize several mechanisms such as adhesion, invasion, phenotype switching and metabolic adaptations, to survive in the host environment and respond. Post-transcriptional and translational regulations have emerged as key regulatory mechanisms ensuring the virulence and survival of fungal pathogens. Through these regulations, fungal pathogens effectively alter their protein pool, respond to various stress, and undergo morphogenesis, leading to efficient and comprehensive changes in fungal physiology. The regulation of virulence through post-transcriptional and translational regulatory mechanisms is mediated through mRNA elements (cis factors) or effector molecules (trans factors). The untranslated regions upstream and downstream of the mRNA, as well as various RNA-binding proteins involved in translation initiation or circularization of the mRNA, play pivotal roles in the regulation of morphology and virulence by influencing protein synthesis, protein isoforms, and mRNA stability. Therefore, post-transcriptional and translational mechanisms regulating the morphology, virulence and drug-resistance processes in fungal pathogens can be the target for new therapeutics. With improved "omics" technologies, these regulatory mechanisms are increasingly coming to the forefront of basic biology and drug discovery. This review aims to discuss various modes of post-transcriptional and translation regulations, and how these mechanisms exert influence in the virulence and morphogenesis of fungal pathogens.

Comparison and evaluation of single-use LMA supreme versus the reusable proseal LMA in paralyzed patients undergoing surgery with controlled ventilation

Background and Aims:

The objective of this prospective randomized blinded study was to assess the safety and efficacy of the laryngeal mask airway (LMA) Supreme as compared with the LMA Proseal.

Material and Methods:

A total of 60 patients were randomised into two groups to either receive a Proseal LMA (PLMA) or Supreme LMA (SLMA) for airway management. The primary outcome was to measure oropharyngeal leak pressure (OLP) in both groups. The secondary outcomes were the measurement of insertion time, insertion success rate, fibreoptic grading, intracuff pressure, ease of ventilation, and airway pressure on standard ventilatory settings and postoperative complications.

Results:

Intracuff pressure increase after 60 minutes of induction was significantly higher in the PLMA group (PLMA 97.43 ± 11.03 cm of H₂O and SLMA 75.17 ± 8.95 cm of H₂O). OLP was recorded after device insertion, after 30 min and after 60 min in each group and was found to be 28.71 ± 2.97, 30.93 ± 2.87, and 31.93 ± 2.72 cm of H₂O in PLMA and 24.84 ± 2.08, 26.73 ± 2.26, and 27.95 ± 2.55 cm of H₂O in SLMA group, respectively. The mean OLP with the SLMA was significantly (p=<.001) lower than PLMA. All the other parameters were comparable in both groups.

Conclusion:

PLMA is better than SLMA as airway device to ventilate at higher airway pressure in paralyzed adult patients. On the basis of our study, we recommend Proseal over Supreme LMA.

143 Therapeutic efficacy and safety of adipose tissue-derived mesenchymal stem cells in treating mastitis and metritis in dairy cattle

Mastitis and metritis are two inflammatory diseases with high economic impact on dairy industry and farmers are losing revenues. Antibiotic treatment for these disease conditions typically achieve suboptimal outcomes. Moreover, emerging antibiotic resistance in mastitis and metritis worldwide has a severe effect on productivity, fertility, and lifespan of animals. A paradigm shift in treatment strategies is much needed for these animals. Attracting properties of mesenchymal stem cells may act as an alternative strategy for treating these diseases. In addition to their ability to differentiate into multiple types of cells, mesenchymal stem cells can orchestrate immune responses and modulate tissue microenvironments. In the present study, we evaluated the safety and efficacy of adipose tissue–derived mesenchymal stem cells (AT-MSC) for mastitis and metritis. A well-characterised adipose-derived stem cell line with 3–5 passages cells were used for treatment for these diseases. In a safety trial, mastitis- and metritis-infected cattle were administered with 1×106 cells of AT-MSC through different routes (local, IV, IV+local). Animals were clinically evaluated during 15 days of the experimental period and blood samples were collected for hemogram determination. The efficacy was checked under both invivo and invitro conditions. Invitro efficiency of AT-MSC was determined using a transwell plate experiment, in which AT-MSC were co-cultured with bacteria (Escherichia coli and Staphylococcus). Invivo efficiency was evaluated by administration of in 2mL (1×106 cells) of AT-MSC dose; then, somatic cell count (SCC) in milk of mastitic cattle and polymorphonuclear (PMN) cell count in cervical vaginal fluid (CVF) of metritic cattle were determined. Gene expression profiling of antimicrobial (cathelicidin, lipocalin, cystatin) and anti-inflammatory (IL-4, IL-6, IL-10) peptides were quantified in all groups: IV, local, IV+local, and control ATB (antibiotic). Allogenic AT-MSC did not induce any immunological rejection response in treated animals. A significant reduction of bacteria in CVF invitro when co-cultured with AT-MSC was observed. The PMN count was significantly reduced in CVF of the IV+local group. The SCC in milk of mastitic animals was decreased in the local (intramammary) group. Maximum expression of IL-6, IL-10, cathelicidin, lipocalin, and cystatin and angiopoietin genes were observed on Day 3 followed by Day 7 in the local group in case of mastitis. In metritis, expression of IL-6, IL-10, cathelicidin, lipocalin, cystatin, and angiopoietin were observed at Day 3 in the IV+local group. All mastitic and metritic cattle were completely and permanently cured within 30 days after treatment with mesenchymal stem cells. In conclusion, we provide initial evidence for the use of allogenic AT-MSC and their safety and efficacy to treat mastitis and metritis in dairy cattle.

Improvement of Ejection Fraction in Patients undergoing Coronary Artery Bypass Grafting with Impaired Left Ventricular Function

Background Myocardial revascularization surgery has shown better long term survival expectancy compared to medical therapy in patient with impaired left ventricular function. Objective To evaluate the change in ejection fraction after 90 days in patients who underwent coronary artery bypass surgery and had preoperative left ventricular ejection fraction of less than and equal to 45% in a single cardiac center of Nepal over the period of 2 years. Method Out of 82 eligible patients during 2 years, 3 patients expired in immediate postoperatively and 24 patients had loss of 90 days' follow up. So, they were excluded from the study. Total 55 patients were taken for the study for whom statistical analysis was done to compare preoperative ejection fraction with post-operative 90 days' ejection fraction. Result Single vessel disease was present in 2(3.6%) patients, double vessel disease in 7(12.7%) patients and triple vessel disease in 46(83.6%) of the patients. In 2(3.6%) patients 2 grafts, in 18(32.7%) patients 3 grafts, in 33(60%) patients 4 grafts and in 2(3.6%) patients 5 grafts were placed for revascularization. The mean left ventricular EF in preoperative patients was 37.12±5.69% which improved to 45.80±10.00% in postoperative follow up at 90 days which was statistically significant (p=0.000). Conclusion Surgical revascularization of myocardium in preoperatively impaired left ventricular function patients helps improve left ventricular ejection fraction postoperatively. So we suggest surgical revascularization in patient with low ejection fraction for improvement of myocardial function. Hence improve survival rate in these patients.

eIF2α interactions with mRNA control accurate start codon selection by the translation preinitiation complex

In translation initiation, AUG recognition triggers rearrangement of the 48S preinitiation complex (PIC) from an open conformation to a closed state with more tightly-bound Met-tRNAi. Cryo-EM structures have revealed interactions unique to the closed complex between arginines R55/R57 of eIF2α with mRNA, including the -3 nucleotide of the 'Kozak' context. We found that R55/R57 substitutions reduced recognition of a UUG start codon at HIS4 in Sui- cells (Ssu- phenotype); and in vitro, R55G-R57E accelerated dissociation of the eIF2·GTP·Met-tRNAi ternary complex (TC) from reconstituted PICs with a UUG start codon, indicating destabilization of the closed complex. R55/R57 substitutions also decreased usage of poor-context AUGs in SUI1 and GCN4 mRNAs in vivo. In contrast, eIF2α-R53 interacts with the rRNA backbone only in the open complex, and the R53E substitution enhanced initiation at a UUG codon (Sui- phenotype) and poor-context AUGs, while reducing the rate of TC loading (Gcd- phenotype) in vivo. Consistently, R53E slowed TC binding to the PIC while decreasing TC dissociation at UUG codons in vitro, indicating destabilization of the open complex. Thus, distinct interactions of eIF2α with rRNA or mRNA stabilize first the open, and then closed, conformation of the PIC to influence the accuracy of initiation in vivo.

Label-free sensing of exosomal MCT1 and CD147 for tracking metabolic reprogramming and malignant progression in glioma

Malignant glioma is a fatal brain tumor whose pathological progression is closely associated with glycolytic reprogramming, leading to the high expression of monocarboxylate transporter 1 (MCT1) and its ancillary protein, cluster of differentiation 147 (CD147) for enhancing lactate efflux. In particular, malignant glioma cells (GMs) release tremendous number of exosomes, nanovesicles of 30 to 200 nm in size, promoting tumor progression by the transport of pro-oncogenic molecules to neighboring cells. In the present study, we found that hypoxia-induced malignant GMs strongly enhanced MCT1 and CD147 expression, playing a crucial role in promoting calcium-dependent exosome release. Furthermore, it was first identified that hypoxic GMs-derived exosomes contained significantly high levels of MCT1 and CD147, which could be quantitatively detected by noninvasive localized surface plasmon resonance and atomic force microscopy biosensors, demonstrating that they could be precise surrogate biomarkers for tracking parent GMs' metabolic reprogramming and malignant progression as liquid biopsies.

Impact of antagonistic crustaceans on the population of Aedes aegypti L. larvae under laboratory conditions

BACKGROUND & OBJECTIVES

Dengue and chikungunya are two mosquito-borne viral diseases transmitted by Aedes mosquito species and are a great public health concern in India. The present study was aimed to check the influence of antagonistic crustaceans, especially Mesocyclops aspericornis and Daphnia magna on Ae. aegypti L. mosquito population.

METHOD

Variable ratios of these crustaceans (Aedes: Mesocyclops: Daphnia) against Ae. aegypti larvae were tested by putting them in plastic beakers having dechlorinated water along with yeast stock solution provided as food, and kept in BOD incubator at a temperature of 26 ±1°C.

RESULTS

Out of all tested concentrations, 1:1:3 where the number of D. magna was thrice the number of Mesocyclops and Aedes; larvae showed a significant delay of 5-6 days in the developmental period. Maximum reduction in the emergence of females was recorded in the ratio 1:1:3, i.e. only 6.5 ± 0.47 females emerged when Daphnia used thrice the number of Aedes larvae. Body size of both males and females emerged from treated sets was found to be significantly reduced. The longevity of adults was also reduced from 8-17 days to 5-8 days in the case of males and from 14-26 days to 5-9 days in females.

INTERPRETATION & CONCLUSION

Among variable ratios tested under laboratory conditions, 1:1:2 and 1:1:3 ratios were found to be the effective ratios that greatly reduced the development duration, survivorship of larvae, and the number of larvae emerging into adulthood. Thus, antagonistic crustaceans specifically Mesocyclops and Daphnia can be used as biocontrol agents for the sustainable control of container breeding mosquitoes.

P1530 Dense spontaneous echo contrast and thrombus in patients on new oral anticoagulant and warfarin therapy: a retrospective audit

Background

Cardioembolic stroke is a known complication of atrial fibrillation (AF), which is increasing in global prevalence. Spontaneous echo contrast (SEC) in the left atrium (LA) is a precursor for thrombus formation detected on transesophageal echocardiography (TEE). There is limited data regarding the prevalence of dense SEC and/or left atrial thrombus (LAT) detected by TEE in patients on novel oral anticoagulants (NOACs) compared with Warfarin.

Purpose

To determine and compare the prevalence of dense SEC and/or LAT among patients with AF/atrial flutter undergoing TEE while on continuous NOAC or Warfarin therapy.

Methods

Retrospective analysis of prospectively entered data for all patients who were on continuous oral anticoagulants and underwent TEE with DC cardioversion, over a 9-year period (1st January 2011 to 31st December 2018) at a public teaching hospital in NSW, Australia. SEC was classified according to emptying flow velocities, as per the European Association of Cardiovascular Imaging guidelines.

Results

Among the 195 patients, 94 (48%) patients were on NOAC therapy (52% Apixaban, 25% Rivaroxaban, 23% Dabigatran) while 101 (52%) patients were on Warfarin. There was no difference in age (mean ± SD: 64 ± 12 vs. 65 ± 13, p = 0.71) or proportion of males (71% vs 69%, p = 0.76) between patients on NOAC therapy compared with Warfarin. However, the NOAC therapy group had a lower prevalence of ischaemic heart disease (IHD) (18% vs. 33%, p &lt; 0.05) and chronic kidney disease (CKD) (2% vs. 19%, p &lt; 0.001), in addition to a lower CHA2DS2-VASc score (2.1 ± 1.7 vs 2.7 ± 1.7, p = 0.03) and higher haemoglobin levels (145.3 ± 19 vs 133.8 ± 24, p = 0.001). The overall rate of dense SEC and/or LAT detected by TEE was 9.7%. There was no significant difference in the prevalence of dense SEC and/or LAT between patients on NOACs and Warfarin (6.4% vs. 12.9%, p = 0.13). On multivariable analysis of IHD, CKD, Warfarin, NOACs and CHA2DS2-VASc score, there was no significant difference in prevalence of SEC/LAT between Warfarin and NOACs.

Conclusions

In this study, 6.4% of patients on continuous NOACs and 12.9% of patients on Warfarin therapy had dense SEC and/or LAT detected by TEE. Although the trend towards higher rates of dense SEC and pre-thrombus in the Warfarin group did not reach statistical significance, it still holds clinical significance as these patients cannot be cardioverted. Therefore, these data support the need to consider anticoagulant optimisation in the overall management of patients with SEC.

A network of eIF2β interactions with eIF1 and Met-tRNAi promotes accurate start codon selection by the translation preinitiation complex

In translation initiation, a 43S preinitiation complex (PIC) containing eIF1 and a ternary complex (TC) of GTP-bound eIF2 and Met-RNA_i scans the mRNA for the start codon. AUG recognition triggers eIF1 release and rearrangement from an open PIC conformation to a closed state with more tightly-bound Met-tRNA_i (P_IN state). Cryo-EM models reveal eIF2β contacts with eIF1 and Met-tRNA_i exclusive to the open complex that should destabilize the closed state. eIF2β or eIF1 substitutions disrupting these contacts increase initiation at UUG codons, and compound substitutions also derepress translation of GCN4, indicating slower TC recruitment. The latter substitutions slow TC loading while stabilizing TC binding at UUG codons in reconstituted PICs, indicating a destabilized open complex and shift to the closed/P_IN state. An eIF1 substitution that should strengthen the eIF2β:eIF1 interface has the opposite genetic and biochemical phenotypes. eIF2β is also predicted to restrict Met-tRNA_i movement into the closed/P_IN state, and substitutions that should diminish this clash increase UUG initiation in vivo and stabilize Met-tRNA_i binding at UUG codons in vitro with little effect on TC loading. Thus, eIF2β anchors eIF1 and TC to the open complex, enhancing PIC assembly and scanning, while impeding rearrangement to the closed conformation at non-AUG codons.

Comparative study of fiber-optic guided tracheal intubation through intubating laryngeal mask airway LMA Fastrach™ and i-gel in adult paralyzed patients

Background:

The i-gel is a novel and innovative supraglottic airway management device used both as an airway rescue device and as a conduit for fiberoptic intubation. In this prospective randomized study, we compared fiberoptic-guided tracheal intubation through the i-gel and LMA Fastrach™ in adult paralyzed patients.

Materials and Methods:

After ethical committee approval and written informed consent, 60 patients of either sex were randomly allocated to either group of supraglottic airway device (SGAD). After successful insertion of the SGAD, the fiberoptic bronchoscope (FOB)-guided tracheal intubation was done through the respective SGAD. The primary objectives were the ease and time taken for fiberoptic-guided intubation in either group. Secondary variables included time taken for successful placement of SGAD, ease of insertion of SGAD, airway seal pressure, ease and time of removal of SGAD, variation in hemodynamic parameters, and complications if any.

Results:

Time taken for tracheal intubation in LMA Fastrach™ group was 69.53 ± 5.09 s and for the i-gel group it was 72.33 ± 6.73 s. It was seen that it was easy to insert the endotracheal tube (ETT) in 93.3% patients in the LMA Fastrach™ group and 96.7% patients in the i-gel group. Airway seal pressure was higher for the LMA Fastrach™ group. Both the SGADs were comparable in the number of attempts of insertion, ease of insertion, and insertion time. In addition, the hemodynamic variables noted did not show any increase after insertion of SGAD. There was no difficulty encountered in removal of either SGAD.

Conclusion:

I-gel may be a reliable and cost-effective alternative to LMA Fastrach™ for fibreoptic-guided tracheal intubation.

Abstract P1-08-05: A phase I trial of chemotherapy followed by infusions of activated T cells armed with anti-CD3 and anti-HER2 bispecific antibody for stage III, Her2+ or Her2- breast cancer

Background: The balance in the immune system between immune surveillance and tolerance is known to be associated with the prognosis of breast cancer patients. The aim of this phase I study was to assess the safety of anti-CD3 x anti-HER2Bi bispecific antibody targeted (BAT) activated T cells (TC) in high risk breast cancer patients. The BAT T-cells exhibit anti-HER2 cytotoxicity, proliferate, and secrete immunokines upon tumor engagement.

Methods: High risk adjuvant breast cancer patients were recruited and completed standard adjuvant chemotherapy. BATs were produced by stimulating peripheral blood mononuclear cells (PBMC) obtained by leukapheresis; collected TC were then activated with anti-CD3 monoclonal antibody and expanded in IL-2 for 12-14 days. TC were armed with bispecific antibody and cryopreserved until used. Groups of 3 patients received 20, 40, 80 or 160 x 109 BATs per infusion twice a week for four weeks. All patients were treated at Roger Williams Medical Center.

Results: Nine patients were accrued and all had N3 disease. Eight of 9 patients were ER positive; 2 of 9 were HER2 overexpressing. The median OS has not reached as five of nine patients are still alive. OS range from 14.3 to 154.7 months (as December 11, 2016). Five out of the five patients who are alive have no evidence of disease and 1 patient had a secondary primary that has been successfully treated and she has no evidence of disease. It was feasible to grow up to 160 x 109 BATs and this dose level was tolerable without any cell-based dose limiting toxicities. BATs persisted in the blood for at least a week. BAT infusions induce cellular anti-tumor responses and cytokine responses.

Conclusion: Targeting HER2 positive and negative tumors induced cytotoxic anti-tumor responses, increases in Th1 cytokines and IL-12 serum levels. The prolonged survival in a high risk population suggests that BAT infusions provided a clinical benefit. These results are being confirmed in a phase II trial for metastatic breast cancer.

Citation Format: Dillon P, Rathore R, Thakur A, Colvin G, Kouttab N, Lum L. A phase I trial of chemotherapy followed by infusions of activated T cells armed with anti-CD3 and anti-HER2 bispecific antibody for stage III, Her2+ or Her2- breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-08-05.

179 Xenogeneic and Allogeneic Mesenchymal Stem Cell Transplantation for Treatment of Tibial Bone Fracture in Mice

Among stem cells, mesenchymal stem cells (MSC) are best suited for therapeutic purposes because of their immunomodulatory properties, ability to be isolated from adult animal at any stage, ease of propagation in the laboratory, and so on. The present study was carried out to isolate and characterise MSC from adipose tissue of mouse (Mus musculus), and to test their application for the treatment of fractured tibia bone in mouse. Cattle and buffalo MSC, already cultured and characterised in our laboratory, were used in the present study as xenogeneic MSC to observe the healing in mouse model. Murine Ad-MSC were isolated from mouse inguinal fat pad by enzymatic digestion method and cultured in growth enriching medium in standard culture conditions. To test the therapeutic potential of MSC, 24 mice were divided into 4 groups: control (C), allogeneic (A), cattle xenogeneic (CX), and buffalo xenogeneic (BX) with 6 mice (having tibial bone mechanical fractured) in each group, and had the corresponding MSC cells injected in the fracture area. The control group was not subjected to any kind of MSC treatment. Post-treatment, healing in all groups was examined for 36 days at different intervals (Days 1, 12, 24, and 36) via digital X-ray imaging. A bone healing score was assigned to each mouse per the protocol provided by RUST (Radiographic Union Scale in Tibial bone) fractures. The results of present study showed that murine Ad-MSC were positive for MSC-specific markers CD44, CD90, CD105, and negative for CD34 and CD45 via RT-PCR and immunocytochemistry. The Ad-MSC were also positive for the alkaline phosphatase staining. Statistical analysis, using Proc GLM (SAS Institute Inc., Cary, NC, USA), revealed that the bone healing was significantly different (P < 0.01) between group C (1.708 ± 0.059) and other groups [group A (2.125 ± 0.061), CX (2.167 ± 0.068), BX (2.250 ± 0.068)], suggesting that healing was greater in groups transplanted with MSC compared with control. However, healing between groups transplanted with MSC (A, CX, and BX) was not significantly different (P > 0.05). In conclusion, we have observed the healing potential of MSC in mouse model via allogeneic and xenogeneic MSC transplantation; the healing potential among the A, CX, and BX MSC groups was similar.

Two dimensional allotropes of arsenene with a wide range of high and anisotropic carrier mobility

Considering the rapid development of experimental techniques for fabricating 2D materials in recent years, various monolayers are expected to be experimentally realized in the near future.

170 Effect of Folic Acid Supplementation on In Vitro Maturation of Oocytes and Folate Cycle

Folic acid (vitamin B9) is the principal component of one-carbon (C1) metabolism in mammalian cells. It acts as a coenzyme in C1 unit transfer during nucleotide and amino acid metabolism. Therefore, it is unquestionably essential for the formation of thymidylate (TMP) for DNA synthesis and methylation, which is in turn crucial for post-implantation embryonic brain and nerve chord development. However, the role of folic acid in maturation of oocytes and subsequent blastocyst production is largely ambiguous in different mammalian species. The aim of this study was to investigate the effect of folic acid supplementation on expression of oocyte maturation markers and folate cycle enzymes in cumulus cells in addition to blastocyst development rate in goat. Immature oocytes were isolated from ovaries, and 1600 oocytes were matured in maturation medium (medium-199) supplemented with 0 (control), 50, 100, or 150 µM folic acid (Sigma Aldrich, India), comprising total 400 oocytes in each group in 5 replicates. The oocytes were in vitro fertilized and embryos were cultured for 7 days. Blastocyst rate was calculated in all 4 groups. Cumulus cells from matured oocytes from each group were analysed for the differential expression of oocyte maturation markers: PTX3, PTGS2, CTSB, and CTSS, and folate cycle enzyme transcripts MTR, MAT2A, ACHY, DHFR, and SLC19A1, by qRT-PCR. For statistical analysis, one-way ANOVA was used. The results of present study show that blastocyst rate was significantly higher (P ≤ 0.05) at 50 µM folic acid (21.4 ± 1.2%) compared with control (13.6 ± 0.4%), 100 µM (10.4 ± 0.34%), and 150 µM (7.4 ± 0.54%). However, there was no effect on the number of cleaved embryos among control (72 ± 0.21%), 50 µM (70.6 ± 0.58%), 100 µM (73.75 ± 0.31%), and 150 µM (73.02 ± 0.04%). The expression of the oocyte maturation markers PTX3 and PTGS2 was up-regulated, whereas that of CTSS and CTSSB was down-regulated (P ≤ 0.05), in the 50 µM group, but did not change (P ≤ 0.05) among the other groups. The expression of these genes did not change significantly among the other groups. The expression of genes of the folate cycle, MTR, MAT2A, ACHY, and DHFR, increased (P ≤ 0.05) by 5.7-, 3.6-, 2.2-, and 1.7-fold, respectively, at 50 µM, but did not change (P ≤ 0.05) among the other groups. The expression of SLC19A1 did not change significantly among all the groups. The results of present study show that the supplementation of 50 µM folic acid to the maturation medium results in increased maturation of oocytes, making them more competent for the blastocyst development. Up-regulation of transcripts of folate cycle enzymes at 50 µM might explain the increase in the blastocyst production rate, which further needs to be validated.

180 Increasing GfrA1-Positive Spermatogonial Stem Cell Population of Goat

Spermatogonial stem cells (SSC) form the basis of spermatogenesis and continuous fertility in male. Their meagre population in the testis is a hindrance in the in vitro study of biological activity of these cells. The objective of the present study was to isolate and characterise goat SSC and increase their number during in vitro culture by different methods. Two goat testes (3 to 4 months of age) were collected from the slaughterhouse and transported to the laboratory. The testes were washed and seminiferous tubules were collected and minced in the laminar flow hood. The seminiferous tubules were washed twice with PBS to remove spermatozoa and subjected to double enzymatic digestion (collagenase, 1 mg mL−1, hyaluronidase, 1 mg mL−1, trypsin, 0.05%, and DNaseI, 10 µg mL−1 for 45 min and second digestion with same set of enzymes except trypsin for 30 min). The isolated cells were filtered sequentially through nylon mesh filters of pore size 70 and 40 µm. The cells were plated on DSA-lectin coated dishes for 4 h and the unattached cells were cultured on a Sertoli cell feeder layer prepared by treating with mitomycin-C for 3 h. The cells were cultured in DMEM/F-12 supplemented with human recombinant growth factors (glial cell-derived neurotrpic factor, 10 ng mL−1, fibroblast growth factor FGF, 10 ng mL−1, epidermal growth factor, 20 ng mL−1), 10% fetal bovine serum, and antibiotics. The expression of pluripotency markers (Oct4, Nanog, Sox2) and SSC-specific markers (Thy1, GfrA1, and Uchl1) in the SSC colonies was determined by RT-PCR and immunostaining, after in vitro culture of 3 weeks. The SSC population was enhanced by differential plating, Percoll density gradient (on Day 1) and SSC passaging (by passaging SSC colonies on Day 20). The cells were tagged with GfrA1 antibody and their population was tested by flow cytometry. The SSC colonies started appearing after 7 days and continued to grow in size and number until 3 weeks. The SSC colonies were positive for the pluripotency markers Oct4, Nanog, and Sox2 by RT-PCR and immunostaining. The SSC were also positive for the SSC-specific markers Thy1, GfrA1, and Uchl1 by RT-PCR and immunostaining. Flow cytometry showed that the GfrA1-positive population in the SSC enriched by the differential plating was 11.23%, Percoll density gradient was 23.57%, and by passaging of SSC colonies, after picking and trypsinising with 0.05% trypsin, was 91.23%. In vitro culture of the SSC enriched by these methods also revealed that the number of SSC colonies appearing in the cells enriched by passaging was higher than the other methods. From the results of present study, we conclude that SSC are positive for markers of pluripotency and SSC-specific markers. The SSC population can be enhanced to a very high level following SSC passaging, which is an inexpensive method and does not require expensive instruments like fluorescence- or magnetic-activated cell sorting.