Person: AKKOÇ, TUNÇ
Loading...
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
AKKOÇ
First Name
TUNÇ
Name
12 results
Search Results
Now showing 1 - 10 of 12
Publication Open Access Mesenchymal stem cells differentiate to retinal ganglion-like cells in rat glaucoma model induced by polystyrene microspheres(2023-10-01) ERASLAN, MUHSİN; ÇERMAN, EREN; BOZKURT, SÜHEYLA; AKKOÇ, TUNÇ; ERASLAN M., ÇERMAN E., BOZKURT S., Genç D., Virlan A. T., Demir C. S., Akkoç T., Karaöz E., AKKOÇ T.Aim: The study aimed to evaluate the differentiation ability of intravitreally injected rat bone marrow-derived mesenchymal stem cells (rBM-MSCs) to retinal ganglion-like cells in a polystyrene microsphere induced rat glaucoma model. Materials and Methods: The glaucoma rat model was generated via intracameral injection of 7 microliter polystyrene microspheres. Green fluorescence protein-labeled (GFP) rBM-MSCs were transplanted intravitreally at or after induction of ocular hypertension (OHT), depending on the groups. By the end of the fourth week, flat-mount retinal dissection was performed, and labeled against Brn3a, CD90, GFAP, CD11b, Vimentin, and localization of GFP positive rBM-MSCs was used for evaluation through immunofluorescence staining and to count differentiated retinal cells by flow cytometry. From 34 male Wistar albino rats, 56 eyes were investigated. Results: Flow cytometry revealed significantly increased CD90 and Brn3a positive cells in glaucoma induced and with rBM-MSC injected groups compared to control(P = 0.006 and P = 0.003 respectively), sham-operated (P = 0.007 and P < 0.001 respectively), and only rBM-MSCs injected groups (P = 0.002 and P = 0.009 respectively). Immunofluorescence microscopy revealed differentiation of GFP labeled stem cells to various retinal cells, including ganglion-like cells. rBM-MSCs were observable in ganglion cells, inner and outer nuclear retinal layers in rBM-MSCs injected eyes. Conclusion: Intravitreally transplanted rBM-MSCs differentiated into retinal cells, including ganglion-like cells, which successfully created a glaucoma model damaged with polystyrene microspheres. Promisingly, MSCs may have a role in neuro-protection and neuro-regeneration treatment of glaucoma in the future.Publication Metadata only SARS COV-2 PCR+ hastalarının peptivatör ile etkileşimi sonucu hafıza hücrelerinin incelenmesi(2023-05-25) AKSU, MEHMET BURAK; AKKOÇ, TUNÇ; Yurt C., Durmuş E. R., Sarıgül N., Eşme Y., Kılıç S., Tunca Z., Aksu M. B., Akkoç T.Giriş ve Amaç: SARS COV-2 virüsü, CD4+ ve CD8+ T hücrelerini ve B hücrelerini etkileyerek bağışıklığı aktive etmektedir. CD45RA T hücreleri, antijenleri hatırlamaması ile \"naive\" özelliklere sahipken CD45RO T hücreleri, antijenleri hatırlayıp çoğaldıkları için \"bellek\" T hücreleri olarak kabul edilir. Peptivator SARS-CoV-2 Select, SARS-CoV-2 spesifik CD4+ ve CD8+ T hücrelerini in vitro uyararak efektör sitokinlerin salgılanmasına sebep olup SARS-CoV-2 spesifik T hücrelerinin saptanmasına ve izolasyonuna olanak tanır. Bu çalışmadaki amacımız SARS-COV-2 hastalarının kanından elde edilen lenfositlerin peptivatör ile etkileşimi sonucu hafıza hücrelerinin incelenmesidir. Gereç ve Yöntem: Araştırmamız deneysel tiptedir. Marmara Üniversitesi Pendik Eğitim ve Araştırma Hastanesi Göğüs Hastalıkları polikliniğinde yatan Koronavirüs hastaları, araştırmanın evrenini oluşturmaktadır. T.C. Sağlık Bakanlığı Marmara Üniversitesi Pendik Eğitim ve Araştırma Hastanesi Göğüs Hastalıkları polikliniğinde Koronavirüs hastalığı sebebi ile yatan aşılı ve aşısız, PCR pozitif 18- 50 yaş arası 9 hastadan gönüllü olmaları kaydıyla kan örnekleri toplanmıştır. Hastalardan alınan periferik kanların bir kısmı ile tam kan immünfenotipleme analizi yapılmıştır. Hastalardan alınan periferik kanın bir kısmı ile de mononükleer hücre (PKMH) izolasyonu yapılıp uyarımsız (US), CDmix uyarımlı ve peptivatör ile uyarımı sonrasında akım sitometrisi kullanılarak analizi yapılmıştır. Bulgular: Flow sitometri tam kan immünfenotipleme analizlerinde CD45RO+ oranı aşısız olan grupta 93,6 (±6,76), aşılı grupta 94,2 (±6,07) olarak bulunmuştur. Hastalardan elde edilen PKMH’ler; US, CDmix ve Peptivatör ile kültür edildikten sonra flow sitometri analizlerinde US kültürde CD45RO+FoxP3 oranı aşısız grupta 8,29 (±4,62), aşılı grupta 3,5 (±2,19) olarak bulunmuştur. CDmix kültüründe CD45RO+FoxP3 oranı aşısız grupta 32,6 (±32,4), aşılı grupta 18,8 (±18,6) bulunmuştur. Peptivatör kültüründe CD45RO+Foxp3 oranı aşısız grupta 36,2 (±35,5), aşılı grupta ise 7,24 (±5,94) olarak bulunmuştur. Sonuç: COVID-19’da mRNA teknolojisi ile üretilen BioNTech/Pfizer aşısı enfeksiyon geçiren hastalarda hafıza hücre sayılarını aşısızlara göre arttırmaktadır. Peptivatör etkileşimi ise aşılı PCR+ grupta ve aşısız PCR+ grupta immün sistemi etkilediği ve hafıza hücrelerini arttırdığı gözlenmektedir.Publication Open Access FIP teşhisi konmuş kedilerden elde edilen periferal kan mononükleer hücreler ile kedi overinden elde edilen mezenkimal kök hücrenin immünolojik araştırılması(2023-05-25) AKSU, MEHMET BURAK; AKKOÇ, TUNÇ; Güven N., Erhan M. N., Karayusuf K., Doğanay K., Kılıç S., Tunca Z., Aksu M. B., Akkoç T.Giriş ve Amaç: Coronavirüsler hem insanlarda hem de hayvanlarda hafiften son derece şiddetli enfeksiyonlara kadar değişkenlik göstermektedir. Coronaviruslar çoğunlukla gastroentestinal ve solunum sistemi enfeksiyonlarına neden olurken bazıları ensefaliti ve hepatite neden olmaktadır. Kedilerin Enfeksiyöz Peritonitisi (FIP) ise kedi coronavirüslerinin (FCoV) neden olduğu bir enfeksiyondur. Çalışmamızda ise kedi ovaryum kaynaklı mezenkimal kök hücrelerin (O-MKH), FIP teşhisi konmuş kedilerden elde edilen periferal kan mononükleer hücrelere (PKMH) etkisinin in vitro ortamda araştırılıp değerlendirilmesi amaçlanmaktadır. Gereç ve Yöntem: Projemizde veteriner kliniğinde FIP tanısı konulmuş 5-13 yaşlarındaki kediler çalışmaya dahil edilecektir. Bu süreçte veteriner kliniğine gelen hastalardan FIP pozitif çıkan kedilerden hasta sahiplerinden alınan onam sonrasında 5cc periferal kan örneği alınacak ve Marmara Üniversitesi Tıp Fakültesi immünoloji anabilim dalında PKMH izole edilecektir. Ayrıca, kedi ovaryumlardan MKH izolasyonu gerçekleştirilecektir. İzole edilen PKMH ile O-MKH\"ların (+/-) ko-kültür işlemleri gerçekleştirilecektir. 5 günlük kültür işleminden sonra O-MKH\"nin FIP hasta PMKH\"larının canlılıkları üzerindeki etkileri akım sitometri yöntemi ile analiz edilecektir. Gerekli etik ve kurum izinleri alınmıştır. Bulgular: Yapılan ko-kültür çalışması sonrasında akım sitometri yöntemi ile PKMH’lerin canlılıklarındaki değişimler kıyaslanmıştır. Yapılan analizler sonucunda FIP kedilerin PKMH’ları MKH’nın olmadığı durumlarda canlılık oranı 55.6 (±5.2) iken MKH varlığında canlılıklarının 70.13 (±2.1)’e yükseldiği görülmüştür. Buna ek olarak, apoptoz geçiren PKMH’ların oranı MKH yokluğunda 34.7 (±4.4) iken MKH varlığında 12.7’e (±1.8) düştüğü gözlenmiştir. Hastalardaki PKMH’ların sağlıklı kedilerin durumları ile kıyaslandığında ise FIP hastası PKMH’ların canlılıkları MKH varlığında sağlıklı kedilerin PKMH’ların canlılık seviyesine yükseldiği görülmüştür. Sonuç: FIP hastalığına sahip olan kedilerin PKMH’larındaki canlılık oranının sağlıklı kediye kıyasla canlılık oranının beklendiği gibi daha düşük olduğu görülmüştür. Yine de MKH’nın varlığında FIP hastası kedilerin PKMH’larındaki canlılık seviyesinin sağlıklı kedilerin PKMH’lerin canlılık oranına yükseldiği görülmüştür. Ayrıca, MKH’ların apoptoz geçiren PKMH’ları FIP hastası kedilerde düşürdüğü gözlenmiştir. Elde edilen bu veriler çerçevesinde MKH’ların FIP hastalarında olumlu etkisi olduğu gözlenmektedir.Publication Metadata only Lymphocyte proliferation in common variable immunodeficiency (CVID) patients by carboxyfluorescein succinimidyl ester (CFSE)(2011-01-01) AKKOÇ, TUNÇ; ÖĞÜLÜR, İSMAİL; AYDINER, ELİF; BARIŞ, SAFA; Izgi A., AKKOÇ T., Ogulur I., Tevetoglu A., AYDINER E., BARIŞ S., Bahceciler N., Barlan I.Objective: Common variable immunodeficiency (CVID) is a heterogeneous disease in the group of predominantly antibody deficiencies, which is defined by hypogammaglobulinemia and normal or low level of B cells, and characterized by increased susceptibility to recurrent bacterial infections, autoimmune disorders, and malignancies. In this study, we aimed to investigate the proliferation of the B and T lymphocytes in patients with CVID.Publication Open Access Investigation of Th17 cell differentiation in immunodeficiencies associated with high IgE levels and/or autoimmunity(2011-01-01) AKKOÇ, TUNÇ; ÖĞÜLÜR, İSMAİL; AYDINER, ELİF; BARIŞ, SAFA; AKKOÇ T., Tevetoglu A., Ogulur I., Izgi A., AYDINER E., BARIŞ S., Bahceciler N., Barlan I.Objective: Hyper IgE Syndrome (HIES) and Common Variably Immunodeficiency (CVID) are immuno-deficiency diseases. HIES is characterized by recurrent skin abscesses, pneumonia, mucocutaneous fungal infections, eczama, eosinophilia and high serum IgE levels. CVID is characterized by recurrent bacterial infections in airways and gastrointestinal tract. In this study, differentiation of Th17 cells were aimed to be investigated in CVID and HIES patients.Publication Open Access Cytotoxic effects of different detergent containing children's toothpastes on human gingival epithelial cells(2022-03-01) AKKOÇ, TUNÇ; BİRANT S., Duran Y., AKKOÇ T., Seymen F.Background This study aimed to evaluate possible cytotoxic effects to gingival epithelial cells exposed to children toothpastes containing different detergent. Methods Tissues required for the isolation of human gingival epithelial cells were obtained by biopsy during the extraction of the impacted third molar tooth. Toothpaste solutions of different concentrations were prepared from five different children\"s toothpastes with different detergent contents. Isolated gingival epithelial cells were stimulated with experimental groups consisting of toothpaste solutions (Colgate, Sensodyne, Splat, Nenedent, Perlodent) at different concentrations and a control group consisting of complete Dulbecco\"s modified eagle medium. After the experiments, cell viability was evaluated using flow cytometry. 2 Way ANOVA was used to see the interaction effect of the main effects of toothpaste solution and concentration factors. Pairwise comparisons were made by Tukey post hoc tests. In the study, the significance level was taken as 0.05. Results As a result of the analysis, it was seen that the toothpaste solution and concentration factors and the interactions of these 2 factors were effective on the viable, early apoptotic, late apoptotic and necrotic cell rates. The statistically highest live cell ratios were detected in Splat\"s toothpaste solutions (90.14% at 0.4% concentration) after the control group (90.82%) and the group with the lowest viability values was determined in Colgate group (75.74% at 0.4% concentration) (p < 0.05). Conclusions According to the results of the study, it was observed that toothpastes containing SLS affected the viability of cells more negatively than toothpastes with other detergent contents.Publication Open Access Effect of cDMEM media containing Ectoine on human periodontal ligament mesenchymal stem cell survival and differentiation(2018-06-01) AKKOÇ, TUNÇ; Tuncer Budanur D., Zibandeh N., Genc D., Gokalp M., KAŞALİ K., AKKOÇ T., Sepet E.Background/Aim: Ectoine is an amino acid that can preserve osmotic balance and has more preservative activity than other osmoregulators. There are no published reports on the osmoregulators’ effects on viability or differentiation of dental stem cells. The aim of this study was to investigate the effect of Ectoine as a storage media on the viability and differentiation potential of human periodontal ligament mesenchymal stem cells (hPDLMSCs). Materials and Methods: hPDLMSCs were obtained from impacted third molar teeth. The cells were isolated, submitted to trilineage differentiation, and characterized by flow cytometer (FC). hPDLMSCs were incubated with different media containing Ectoine, complete DMEM (cDMEM), Ectoine+cDMEM, milk, and tap water for 2, 6, 12, and 24 h. The cells were analyzed by FC for viability, early-apoptosis, late apoptosis, and necrosis rates. Osteogenic and fibroblastic differentiation in hPDLMSCs were investigated by Alizarin red stain and vimentin expression. Results: All treated groups showed significant decreases in cell viability after 2 h. Significant increases were detected in the number of dead cells between 2 and 12 h in all groups except the Ectoine+cDMEM group. The deposition of mineral matrix nodules was significantly higher in cells cultured with Ectoine+cDMEM compared with the other media. Higher vimentin expressions were detected in cells cultured with cDMEM and Ectoine+cDMEM media, respectively. Conclusions: Ectoine added to cDMEM media, promoted cell survival plus osteogenic and fibroblastic differentiation of hPDLMSCs.Publication Metadata only Histological and Immunological Evaluation of the Osteogenic Effects of Compact Bone-Delivered Stem Cell on Spongiosis Bone in the Rat Zygomatic Arch Defect Model(2023-09-01) AKKOÇ, TUNÇ; Tatar B. E., Gelbal C., Uslu C., Yılmaz B., Tomruk C., UYANIKGİL Y., AKKOÇ T., Bozkurt M.BACKGROUND: In stem cell applications, apart from bone marrow and adipose tissue, compact bone is also used as an alternative. However, studies on this subject are limited. In our study, we investigated the effect of stem cell derived from compact bone on rat zygomatic arch defect. METHODS: Fifteen rats were included in the study. Five rats were killed to obtain stem cells before the experiment. The rats were divided into 2 groups with 5 rats each. In group 1, compact bone-derived stem cell was applied. In group 2, adipose tissue-derived stem cell was applied. Right zygomatic arch defect was created in rats in both groups. Zygomatic bones were decellularized by cryosurgery. Stem cells were transferred to zygomatic bones. The number of stem cells, stem cell differentiation, and superficial markers obtained from the groups were examined. Histologically, cell structure, osteocyte count and osteopontin scores, elemental composition of the groups, percentages of resemblance to intact bone, osteocytes numbers, and cells were examined by electron microscopy of the bones in the groups after killing. RESULTS: The number of stem cells administered to the groups was 5 × 107 and 3.2 × 107 for group 1 and group 2, respectively (P > 0.05). Histologically, the morphology of the cells in group 1 was found to be healthier than group 2. The number of osteocytes was 97.56 ± 15.4 and 132.93 ± 10.8 in group 1 and group 2, respectively (P 0.05). Osteocyte counts were 10.7 ± 2.8 and 6.1 ± 1.2 in group 1 and group 2, respectively (P 0.05). CONCLUSION: Stem cells obtained from compact bone gave positive results in zygomatic arch defect. This method can also be used as an alternative in stem cell applications.Publication Open Access A farewell to Işıl Barlan(2015-09-01) AKKOÇ, TUNÇ; Kalayci Ö., AKKOÇ T., Wahn U.Publication Open Access TNF-α, IL-1B and IL-6 affect the differentiation ability of dental pulp stem cells(2023-12-01) SAZAK ÖVEÇOĞLU, HESNA; AKKOÇ, TUNÇ; Sonmez Kaplan S., SAZAK ÖVEÇOĞLU H., Genc D., AKKOÇ T.Background: This in vitro study examined the effect of the inflammatory cytokines (tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6) on osteogenic, chondrogenic, and adipogenic differentiation of dental pulp stem cells (DPSCs) which have significant relevance in future regenerative therapies. Methods: DPSCs were isolated from the impacted third molar dental pulp and determined with flow cytometry analysis. DPSCs were divided into into 5 main groups with 3 subdivisions for each group making a total of 15 groups. Experimental groups were stimulated with TNF-α, IL-1β, IL-6, and a combination of all three to undergo osteogenic, chondrogenic, and adipogenic differentiation protocols. Next, the differentiation of each group was examined with different staining procedures under a light microscope. Histological analysis of osteogenic, chondrogenic, and adipogenic differentiated pellets was assessed using a modified Bern score. Statistical significance determined using one-way analysis of variance, and correlations were assessed using Pearson’s test (two-tailed). Results: Stimulation with inflammatory cytokines significantly inhibited the osteogenic, chondrogenic and adipogenic differentiation of DPSCs in terms of matrix and cell formation resulting in weak staining than the unstimulated groups with inflammatory cytokines. On contrary, the unstimulated groups of MSCs have shown to be highly proliferative ability in terms of osteogenic, chondrogenic, and adipogenic differentiation. Conclusions: DPSCs have high osteogenic, chondrogenic, and adipogenic differentiation capabilities. Pretreatment with inflammatory cytokines decreases the differentiation ability in vitro, thus inhibiting tissue formation.