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Reduced Serum Levels of Cluster of Differentiation 200 in Alcohol-Dependent Patients

Chaturvedi A, Rao G, Praharaj SK, Guruprasad KP, Pais V

Alcohol Alcohol, 2020 Jun 25;55(4):391-394.
PMID: 32363396 DOI: 10.1093/alcalc/agaa033

AIM: Chronic alcohol consumption can activate and dysregulate the neuroimmune system which leads to neuroinflammation. Neuroimmune regulatory proteins (NIReg) (e.g. Cluster of Differentiation 200 (CD200)) are the regulators of innate immune response and are responsible for silencing the innate immunity and suppression of inflammation. In this study, we explored the changes of serum levels of CD200 in patients with alcohol dependence at baseline, after one-week alcohol withdrawal and after one-month of alcohol abstinence.
METHODS: Seventeen patients with alcohol dependence admitted for de-addiction treatment and 12 healthy controls were enrolled in the study. Blood samples were collected at baseline, after one-week, and after one-month, and CD200 levels were measured using enzyme-linked immunosorbent assay kit and compared with the healthy controls.
RESULTS: The serum level of the neuroimmune regulatory protein CD200 in alcohol dependent group (at baseline) was significantly lower compared to healthy controls (p=0.003), and increased after one-week, and one-month period.
CONCLUSION: The present study indicates that decrease of CD200 serum levels in alcohol dependent patients and its rise during alcohol withdrawal and abstinence may provide a preliminary evidence of the role of neuroimmune regulatory proteins in neuroadaptation during alcohol withdrawal.

Matched MeSH terms: Antigens, CD/blood*
FcgammaRIIa polymorphism in systemic lupus erythematosus

Tan SY

Kidney Blood Press Res, 2000;23(2):138-42.
PMID: 10765117 DOI: 10.1159/000025967

FcgammaRIIs are the most widely distributed of the Fcgamma receptor family and play an important role in the clearance of immune complexes. Evidence that the FcgammaRIIa-R131 allotype is less able to process and clear immune complexes effectively suggests that this may be a disease susceptibility factor for systemic lupus erythematosus (SLE). Data from studies published thus far do not agree on the potential role of FcgammaRIIa polymorphism in the genetics of SLE. Most studies in fact show no evidence for any correlation between polymorphism of FcgammaRIIa and risk for SLE. However, it remains to be determined whether FcgammaRIIa polymorphism may play a critical role in certain groups of patients, especially in those of differing ethnic background. Polymorphism of FcgammaRIIa may also be important in determining disease phenotype, and identification of this influence may have important implications in patient care and in identifying patients for more aggressive therapy.

Matched MeSH terms: Antigens, CD/genetics*
Fulltext Roles of Sema4D and Plexin-B1 in tumor progression

Ch'ng ES, Kumanogoh A

Mol. Cancer, 2010;9:251.
PMID: 20858260 DOI: 10.1186/1476-4598-9-251

Sema4D, also known as CD100, is a protein belonging to class IV semaphorin. Its physiologic roles in the immune and nervous systems have been extensively explored. However, the roles of Sema4D have extended beyond these traditionally studied territories. Via interaction with its high affinity receptor Plexin-B1, Sema4D-Plexin-B1 involvement in tumor progression is strongly implied. Here, we critically review and delineate the Sema4D-Plexin-B1 interaction in many facets of tumor progression: tumor angiogenesis, regulation of tumor-associated macrophages and control of invasive growth. We correlate the in vitro and in vivo experimental data with the clinical study outcomes, and present a molecular mechanistic basis accounting for the intriguingly contradicting results from these recent studies.

Matched MeSH terms: Antigens, CD/genetics; Antigens, CD/metabolism*
Intracellular antigen determination by flow cytometry in leukaemic cells

Chin SF, Cheong SK

Malays J Pathol, 1994 Jun;16(1):69-73.
PMID: 16329579

Several fixation and permeabilization techniques that enable the flow cytometric analysis of the cell contents have been introduced in recent years. These methods allow sensitive detection of intracellular antigens that facilitates the diagnosis of certain diseases. We have undertaken in this study to evaluate a simple method of fixation and permeabilization using 2% paraformaldehyde and Tween 20. Intracellular antigens in three different leukaemia cases were analysed. We found that the method was reliable and easy. Intracellular kappa light chains were found in abundance in a case of plasma cell leukaemia. CD3 and CD22 were found in greater amount intracellularly than on the surface in pre-T-ALL and pre-pre B-ALL respectively.

Matched MeSH terms: Antigens, CD/blood*; Antigens, CD/immunology
Epithelial membrane antigen (EMA) or MUC1 expression in monocytes and monoblasts

Leong CF, Raudhawati O, Cheong SK, Sivagengei K, Noor Hamidah H

Pathology, 2003 Oct;35(5):422-7.
PMID: 14555387

AIMS: Epithelial membrane antigen (EMA) or MUC1 belongs to a heterogeneous group of heavily glycosylated proteins and is expressed in most normal and epithelial neoplastic cells. EMA is also expressed in plasma cells, anaplastic large cell lymphoma (Ki-1 antigen), malignant histiocytosis and erythroleukaemia. In 1996, Cheong et al. (Hematology 1996; 1: 223) demonstrated the positive expression of EMA in monoblasts. Since there were very few useful markers for differentiating subtypes of acute myeloid leukaemia with a monocytic component from the those without, a study was conducted to evaluate the prevalence of EMA expression and its relationship with known markers for monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68) in monocytes and monoblasts.
METHODS: EMA detection was performed by flow cytometry in monocytes and monoblasts. EMA expression was compared with other known markers of monocytic-macrophage lineage (CD11c, CD14 and intracellular CD68). Samples of purified monocytes were obtained from 20 healthy volunteers. Twenty-two cases of monocytic AML (M4 and M5) were studied and controls were selected from 20 cases of acute lymphoblastic leukaemia (ALL) and 18 cases of non-monocytic AML (M0, M1, M2, M3, and M7).
RESULTS: EMA was shown to be expressed strongly on the surface of all purified monocytes. EMA expression was observed on blast cells in 18/22 (81.8%) cases of AML M4 and M5, but not in that of non-monocytic AML or ALL. In this study EMA monoclonal antibody has demonstrated a strong association (P<0.001) with all the other known markers of monocytic-macrophage lineage in acute leukaemia subtypes. EMA had also shown 100% specificity and 81.8% sensitivity in the diagnosis of AML M4 and M5.
CONCLUSIONS: The monoclonal antibody EMA (clone E29) is a useful marker in the classification of acute myeloid leukaemia and can be used as a supplementary analysis for the diagnosis of acute leukemia with monocytic involvement.

Matched MeSH terms: Antigens, CD/analysis; Antigens, CD/metabolism
An immunohistochemical study of CD1a and CD83-positive infiltrating dendritic cell density in cervical neoplasia

Hayati AR, Zulkarnaen M

Int J Gynecol Pathol, 2007 Jan;26(1):83-8.
PMID: 17197902

Cervical carcinoma is the second leading cancer in women in Malaysia, after breast cancer. Human papillomavirus (HPV) has been implicated in the development of dysplasia or cervical intraepithelial neoplasia and progression to squamous cell carcinoma. Because of the confinement of the human papillomavirus infection within the epithelial layer, the presence of dentritic cells or Langerhans cells in epithelial layer of the ectocervix is paramount in producing immune response. The mature dentritic cells express CD83 and high CD40/80/86, whereas the immature cells express CD1a and low CD40/80/86. By identifying CD1a and CD83, theoretically, both immature and mature dentritic cell populations can be studied. In view of the facts, we investigated the infiltrating cell density of mature and immature dentritic cells in cervical neoplasia.

Matched MeSH terms: Antigens, CD/immunology; Antigens, CD/metabolism*; Antigens, CD1/immunology; Antigens, CD1/metabolism*
Fulltext Qualitative flow cytometric analysis of Malaysian myelodysplastic syndromes (MDS) patients

Mohadese Hashem B, Ramasamy R, Sabariah MN, Seman Z

Med J Malaysia, 2012 Feb;67(1):77-80.
PMID: 22582553 MyJurnal

Myelodysplastic syndromes (MDS) are a group of haematological malignancies categorized by ineffective hematopoiesis that result in dysplasia. Although morphological diagnosis is a traditional and standard technique that is used for the diagnosis of MDS, the heterogeneous blood and bone marrow characteristics of MDS patients can potentially obscure the right diagnosis. Thus, we have utilized flow cytometric immunophenotyping as a supportive mechanism to obtain a more accurate and faster method for detection of abnormal markers in MDS. Flow cytometry was used for analyzing bone marrow samples from newly diagnosed MDS patients to investigate the abnormal antigen expression patterns in granulocytic, monocytic, erythroid, lymphoid lineages and myeloid precursors. The results were compared with those obtained from cases that had Idiopathic Thrombocytopenic Purpura (ITP) as a control. The most common abnormality found in the granulocytic lineage was the decrease of CD10. Low expressions of CD13 were the most frequent abnormality in the monocytic lineage. The erythroid lineage was found to have low expression of CD235A+/CD71+, reduce of CD71 and decreased CD235a. In conclusion, this method is useful for confirming cases in which it is difficult to make a diagnosis by morphology.

Matched MeSH terms: Antigens, CD/analysis; Antigens, CD13/analysis; Antigens, CD11b/analysis
Fulltext Small cell variant of anaplastic large cell lymphoma with positive immunoreactivity for CD99

Shiran MS, Tan GC, Sabariah AR, Chye PC, Pathmanathan R

Med J Malaysia, 2008 Jun;63(2):150-1.
PMID: 18942305 MyJurnal

A 13 year old boy presented with a huge mass on his right arm of 6 months duration. Histopathological examination revealed sheets of malignant small round blue cells with immunopositivity for LCA, CD43, CD45Ro, CD30, EMA, ALK-1 and CD99, and negativity for CD20, TdT, myogenin, myoD1, NSE, bcl-6, bcl-2 and CD10. Fluorescent In-Situ Hybridization (FISH) testing excluded the diagnosis of Ewing's sarcoma/PNET. Pathologists need to be aware of the diagnosis of a small cell variant of ALCL, as well as of the fact that CD99 expression commonly occurs in cases of ALK-positive ALCL, in order to distinguish this entity from Ewing's sarcoma/PNET.

Matched MeSH terms: Antigens, CD/immunology*
Influence of race, age and sex on the lymphocyte subsets in peripheral blood of healthy Malaysian adults

Choong ML, Ton SH, Cheong SK

Ann. Clin. Biochem., 1995 Nov;32 ( Pt 6):532-9.
PMID: 8579284

The lymphocyte subsets in the peripheral blood of healthy Malaysian adults (212 subjects, age 18-71 years) were analysed using a flow cytometer FACScan in an effort to establish a reference range for the lymphocyte subsets. The lymphocyte subsets studied were T cells (CD3), B cells (CD19), natural killer (NK) cells (CD3- CD16+/CD56+), helper/inducer cells (CD4), cytotoxic/suppressor cells (CD8) and the helper/suppressor ratio (CD4/CD8). The distributions of T cells, CD4 cells and CD8 cells were symmetric about their means while B cells, NK cells and CD4/CD8 ratio followed a skewed distribution. Differences in race were observed for T cells, NK cells, CD4 cells and CD4/CD8 ratio where the Indians were significantly different from the Malays and the Chinese (higher T cells, CD4 cells and CD4/CD8 ratio and lower NK cells). The B cells were significantly lower in the Chinese than the Malays and the Indians. Age differences were seen only in the Chinese where increased CD4 cells and CD4/CD8 ratio, and decreased CD8 cells were observed. A sex difference was observed only in the Chinese where the CD4/CD8 ratio was significantly higher in females than males.

Matched MeSH terms: Antigens, CD/analysis
Autoantibodies to tetraspanins (CD9, CD81 and CD82) in demyelinating diseases

Miyaji K, Paul F, Shahrizaila N, Umapathi T, Yuki N

J Neuroimmunol, 2016 Feb 15;291:78-81.
PMID: 26857499 DOI: 10.1016/j.jneuroim.2015.12.012

Tetraspanin family proteins, CD9, CD81 and CD82 are expressed in the oligodendrocytes and Schwann cells. We investigated autoantibodies to tetraspanin proteins in patients with demyelinating diseases. Sera were collected from 119 multiple sclerosis patients, 19 neuromyelitis optica, 42 acute inflammatory demyelinating polyneuropathy, 23 chronic inflammatory demyelinating polyneuropathy and 13 acute motor axonal neuropathy as well as 55 healthy controls. Few multiple sclerosis and acute inflammatory demyelinating polyneuropathy patients had autoantibodies that were weakly reactive to CD9 or CD81 but the significance is unclear. It is unlikely that these autoantibodies are pathogenic or serve as potential biomarkers in demyelinating diseases.

Matched MeSH terms: Antigens, CD/immunology*; Antigens, CD82/immunology; Antigens, CD81/immunology; Antigens, CD9/immunology
Fulltext Isolation, characterization and the multi-lineage differentiation potential of rabbit bone marrow-derived mesenchymal stem cells

Tan SL, Ahmad TS, Selvaratnam L, Kamarul T

J Anat, 2013 Apr;222(4):437-50.
PMID: 23510053 DOI: 10.1111/joa.12032

Mesenchymal stem cells (MSCs) are recognized by their plastic adherent ability, fibroblastic-like appearance, expression of specific surface protein markers, and are defined by their ability to undergo multi-lineage differentiation. Although rabbit bone marrow-derived MSCs (rbMSCs) have been used extensively in previous studies especially in translational research, these cells have neither been defined morphologically and ultrastructurally, nor been compared with their counterparts in humans in their multi-lineage differentiation ability. A study was therefore conducted to define the morphology, surface marker proteins, ultrastructure and multi-lineage differentiation ability of rbMSCs. Herein, the primary rbMSC cultures of three adult New Zealand white rabbits (at least 4 months old) were used for three independent experiments. rbMSCs were isolated using the gradient-centrifugation method, an established technique for human MSCs (hMSCs) isolation. Cells were characterized by phase contrast microscopy observation, transmission electron microscopy analysis, reverse transcriptase-polymerase chain reaction (PCR) analysis, immunocytochemistry staining, flow cytometry, alamarBlue(®) assay, histological staining and quantitative (q)PCR analysis. The isolated plastic adherent cells were in fibroblastic spindle-shape and possessed eccentric, irregular-shaped nuclei as well as rich inner cytoplasmic zones similar to that of hMSCs. The rbMSCs expressed CD29, CD44, CD73, CD81, CD90 and CD166, but were negative (or dim positive) for CD34, CD45, CD117 and HLD-DR. Despite having similar morphology and phenotypic expression, rbMSCs possessed significantly larger cell size but had a lower proliferation rate as compared with hMSCs. Using established protocols to differentiate hMSCs, rbMSCs underwent osteogenic, adipogenic and chondrogenic differentiation. Interestingly, differentiated rbMSCs demonstrated higher levels of osteogenic (Runx2) and chondrogenic (Sox9) gene expressions than that of hMSCs (P 0.05). rbMSCs possess similar morphological characteristics to hMSCs, but have a higher potential for osteogenic and chondrogenic differentiation, despite having a lower cell proliferation rate than hMSCs. The characteristics reported here may be used as a comprehensive set of criteria to define or characterize rbMSCs.

Matched MeSH terms: Antigens, CD/analysis
Extramedullary CD20-positive B-lymphoblastic lymphoma in a 5-year-old child: A diagnostic challenge

Abdul Jalil D, Raja Sabudin RZA, Tang YL, Masir N

Malays J Pathol, 2020 Aug;42(2):273-276.
PMID: 32860381

INTRODUCTION: Lymphoblastic leukaemia/lymphoma may present as an isolated extramedullary mass, which includes the musculoskeletal region involvement with normal or near-normal blood counts. The tumour may be in the form of B or T-lymphoblastic leukaemia/lymphoma. The clinical features and histological morphology of extramedullary B-lymphoblastic lymphoma (B-LBL) may mimic mature B-cell neoplasms, thus posing a diagnostic challenge. Arriving at the right diagnosis is crucial because these two diseases differ in their prognosis and management. A high index of suspicion is therefore important so as not to miss the correct diagnosis. The diagnosis may be overlooked because the clinical presentation may not be typical of B-LBL or the blood counts do not show any abnormalities. In this report, we highlight one such case where the diagnosis of B-LBL was missed because of its atypical presentation.

Matched MeSH terms: Antigens, CD/metabolism*
Study of the CTLA-4 gene polymorphisms in systemic lupus erythematosus (SLE) samples from Malaysia

Chua KH, Puah SM, Chew CH, Tan SY, Lian LH

Ann Hum Biol, 2010 Apr;37(2):274-80.
PMID: 19951233 DOI: 10.3109/03014460903325185

In this study, we investigated the polymorphisms of the exon 1 (+49A/G), promoter sites (-1722T/C, -1661A/G, -318C/T), and 3'-untranslated region (3'-UTR) (+6230 A/G) of the CTLA-4 gene in systemic lupus erythematosus (SLE) affected patients. Polymerase chain reaction-restriction fragment length polymorphism was used to determine genotypes of these five markers in 130 SLE patients and 130 healthy controls. Of the five tested polymorphisms, there was no statistical significant difference between the genotypic and allelic frequencies of patients with SLE and controls. Hence, we propose that the CTLA-4 gene does not play a major role in the genetic susceptibility to the development of SLE in the Malaysian population.

Matched MeSH terms: Antigens, CD/genetics*
Fulltext Human respiratory epithelial cells from nasal turbinate expressed stem cell genes even after serial passaging

Ruszymah BH, Izham BA, Heikal MY, Khor SF, Fauzi MB, Aminuddin BS

Med J Malaysia, 2011 Dec;66(5):440-2.
PMID: 22390097 MyJurnal

Current development in the field of tissue engineering led to the idea of repairing and regenerating the respiratory airway through in vitro reconstruction using autologous respiratory epithelial (RE). To ensure the capability of proliferation, the stem cell property of RE cells from the nasal turbinate should be evaluated. Respiratory epithelial cells from six human nasal turbinates were harvested and cultured in vitro. The gene expression of FZD-9 and BST-1 were expressed in passage 2 (P2) and passage 4 (P4). The levels of expression were not significant between both passages. The RE cells exhibit the stem cell properties, which remains even after serial passaging.

Matched MeSH terms: Antigens, CD/genetics; Antigens, CD/metabolism
Fulltext Experimental production of clinical-grade dendritic cell vaccine for acute myeloid leukemia

Tan YF, Sim GC, Habsah A, Leong CF, Cheong SK

Malays J Pathol, 2008 Dec;30(2):73-9.
PMID: 19291915 MyJurnal

Dendritic cells (DC) are professional antigen presenting cells of the immune system. Through the use of DC vaccines (DC after exposure to tumour antigens), cryopreserved in single-use aliquots, an attractive and novel immunotherapeutic strategy is available as an option for treatment. In this paper we describe an in vitro attempt to scale-up production of clinical-grade DC vaccines from leukemic cells. Blast cells of two relapsed AML patients were harvested for DC generation in serum-free culture medium containing clinical-grade cytokines GM-CSF, IL-4 and TNF-alpha. Cells from patient 1 were cultured in a bag and those from patient 2 were cultured in a flask. The numbers of seeding cells were 2.24 x 10(8) and 0.8 x 10(8), respectively. DC yields were 10 x 10(6) and 29.8 x 10(6) cells, giving a conversion rate of 4.7% and 37%, respectively. These DC vaccines were then cryopreserved in approximately one million cells per vial with 20% fresh frozen group AB plasma and 10% DMSO. At 12 months and 21 months post cryopreservation, these DC vaccines were thawed, and their sterility, viability, phenotype and functionality were studied. DC vaccines remained sterile up to 21 months of storage. Viability of the cryopreserved DC in the culture bag and flask was found to be 50% and 70% at 12 months post cryopreservation respectively; and 48% and 67% at 21 months post cryopreservation respectively. These DC vaccines exhibited mature DC surface phenotypic markers of CD83, CD86 and HLA-DR, and negative for haemopoietic markers. Mixed lymphocyte reaction (MLR) study showed functional DC vaccines. These experiments demonstrated that it is possible to produce clinical-grade DC vaccines in vitro from blast cells of leukemic patients, which could be cryopreserved up to 21 months for use if repeated vaccinations are required in the course of therapy.

Matched MeSH terms: Antigens, CD/immunology; Antigens, CD/metabolism
Human Fc gamma receptor IIA (FcgammaRIIA) genotyping and association with systemic lupus erythematosus (SLE) in Chinese and Malays in Malaysia

Yap SN, Phipps ME, Manivasagar M, Tan SY, Bosco JJ

Lupus, 1999;8(4):305-10.
PMID: 10413210 DOI: 10.1191/096120399678847876

SLE is an autoimmune and polygenic disorder characterized by an accumulation and deposition of immune complexes. Several studies have indicated differential impact of FcgammaR polymorphism genotypes in different ethnic groups studied. The Fc receptor for IgG class IIA gene (FcgammaRIIA) occurs in two allelic forms. The allele FcgammaRIIA-H131 encodes a receptor with a histidine at the 131 amino acid position; the other allele FcgammaRIIA-R131 encodes an arginine. This polymorphism is believed to determine the affinity of the receptor for hIgG2 in immune complexes. FcgammaRIIA-H131 has a higher capacity for hIgG2 compared to FcgammaRIIA-R131 as measured by in vitro studies of insoluble immune complex clearance. We have investigated the polymorphism for FcgammaRIIA using a novel polymerase chain reaction-allele specific primer (PCR-ASP) method designed specifically to distinguish the two allelic forms. Our studies were based on 175 Chinese and 50 Malays SLE patients as well as 108 and 50 ethnically matched healthy controls for the respective groups. Analysis of the data (chi2 test with Yates correction factors and odds ratios) revealed that there were no significant differences between SLE patients and controls. We have not found evidence of a protective effect conferred by FcgammaRIIA-H131 in the ethnic groups studied.

Matched MeSH terms: Antigens, CD/genetics*; Antigens, CD/immunology*
Long-term outcome of hematopoietic stem cell transplantation for IL2RG/JAK3 SCID: a cohort report

Abd Hamid IJ, Slatter MA, McKendrick F, Pearce MS, Gennery AR

Blood, 2017 04 13;129(15):2198-2201.
PMID: 28209722 DOI: 10.1182/blood-2016-11-748616

Hematopoietic stem cell transplantation (HSCT) cures the T-lymphocyte, B-lymphocyte, and natural killer (NK)-cell differentiation defect in interleukin-2 γ-chain receptor (IL2RG)/JAK3 severe combined immunodeficiency (SCID). We evaluated long-term clinical features, longitudinal immunoreconstitution, donor chimerism, and quality of life (QoL) of IL2RG/JAK3 SCID patients >2 years post-HSCT at our center. Clinical data were collated and patients/families answered PedsQL Generic Core Scale v4.0 questionnaires. We performed longitudinal analyses of CD3+, CD4+ naive T-lymphocyte, CD19+, and NK-cell numbers from pretransplant until 15 years posttransplant. Thirty-one of 43 patients (72%) survived. Median age at last follow-up was 10 years (range, 2-25 years). Twenty-one (68%) had persistent medical issues, mainly ongoing immunoglobulin replacement (14; 45%), cutaneous viral warts (7; 24%), short stature (4; 14%), limb lymphoedema (3; 10%), and bronchiectasis (2; 7%). Lung function was available and normal for 6 patients. Longitudinal analysis demonstrated sustained CD3+, CD19+, and NK-cell output 15 years post-HSCT. CD4+ naive lymphocyte numbers were better in conditioned vs unconditioned recipients (P, .06). B-lymphocyte and myeloid chimerism were highly correlated (ρ, 0.98; P < .001). Low-toxicity myeloablative conditioning recipients have better B-lymphocyte/myeloid chimerism and are free from immunoglobulin replacement therapy. IL2RG/JAK3 SCID survivors free from immunoglobulin replacement have normal QoL.

Matched MeSH terms: Antigens, CD/genetics; Antigens, CD/immunology
Fulltext Immunological history governs human stem cell memory CD4 heterogeneity via the Wnt signaling pathway

Kared H, Tan SW, Lau MC, Chevrier M, Tan C, How W, et al.

Nat Commun, 2020 02 10;11(1):821.
PMID: 32041953 DOI: 10.1038/s41467-020-14442-6

The diversity of the naïve T cell repertoire drives the replenishment potential and capacity of memory T cells to respond to immune challenges. Attrition of the immune system is associated with an increased prevalence of pathologies in aged individuals, but whether stem cell memory T lymphocytes (TSCM) contribute to such attrition is still unclear. Using single cells RNA sequencing and high-dimensional flow cytometry, we demonstrate that TSCM heterogeneity results from differential engagement of Wnt signaling. In humans, aging is associated with the coupled loss of Wnt/β-catenin signature in CD4 TSCM and systemic increase in the levels of Dickkopf-related protein 1, a natural inhibitor of the Wnt/β-catenin pathway. Functional assays support recent thymic emigrants as the precursors of CD4 TSCM. Our data thus hint that reversing TSCM defects by metabolic targeting of the Wnt/β-catenin pathway may be a viable approach to restore and preserve immune homeostasis in the context of immunological history.

Matched MeSH terms: Antigens, CD/genetics; Antigens, CD/metabolism
Fulltext Construction of a full-thickness of tissue-engineered oral mucosa (TEOM) based on immortalised keratinocytes

Zulfahmi Said, Hellen Colley, Craig Murdoch

Malaysian Journal of Medicine and Health Sciences, 2019;15(107):49-49.
MyJurnal

Introduction: Tissue-engineered oral mucosa (TEOM) is increasingly being used to model oral mucosal diseases and to assess drug toxicity. Current TEOM models are constructed using normal oral fibroblasts (NOF) contained within a hydrogel matrix with normal oral keratinocytes (NOK) cultured on top. NOK are not commercially available and suffer from donor-to-donor variability. Therefore, oral mucosal models based on immortalised keratinocytes may offer advantages over NOK-based models. The objective of this study was to construct and characterise the TEOM developed using TERT2-immortalised oral keratinocyte (FNB6) cells and validate its similarity to normal oral muco-sal tissue. Methods: TEOM were constructed by culturing FNB6 cells on top of a NOF-populated collagen type-1 hydrogel in tissue culture transwell inserts cultured at an air-to-liquid interface and collected at 14 day. TEOM were subjected to morphological (H&E and PAS), ultrastructural (TEM) and immunohistological (Ki-67, cytokeratin 14 and E-cadherin) analysis. Results: Histologically TEOM mimicked native oral mucosa displaying a stratified epithelium, fibroblast-containing connective tissue and basement membrane. Furthermore, TEM confirmed the presence of des-mosomes and hemi-desmosomes in the epithelium. IHC revealed expression of differentiation markers (cytokeratin 14), proliferation (Ki-67), cell adhesion (E-cadherin). Conclusion: FNB6 mucosal models able to mimic native oral mucosa structure. It has potential for drug delivery and toxicity evaluation, and replacing models based on NOK where access to primary cells is limited.

Matched MeSH terms: Antigens, CD
Fulltext Senescent HUVECs-secreted exosomes trigger endothelial barrier dysfunction in young endothelial cells

Wong PF, Tong KL, Jamal J, Khor ES, Lai SL, Mustafa MR

EXCLI J, 2019;18:764-776.
PMID: 31611757 DOI: 10.17179/excli2019-1505

Accumulation of senescent endothelial cells can cause endothelium dysfunction which eventually leads to age-related vascular disorders. The senescent-associated secretory phenotype (SASP) cells secrete a plethora of soluble factors that negatively influence the surrounding tissue microenvironment. The present study sought to investigate the effects of exosomes, which are nano-sized extracellular vesicles known for intercellular communications secreted by SASP cells on young endothelial cells. Exosomes were isolated from the condition media of senescent human umbilical vein endothelial cells (HUVECs) and then confirmed by the detection of exosome specific CD63 and CD9 expressions, electron microscopy and acetylcholinesterase assay. The purified exosomes were used to treat young HUVECs. Exposure to exosomes repressed the expression of adherens junction proteins including vascular endothelial (VE)-cadherin and beta-catenin, decreased cell growth kinetics and impaired endothelial migration potential of young endothelial cells. These findings suggest that senescent HUVECs-secreted exosomes could disrupt barrier integrity that underpins endothelial barrier dysfunction in healthy young endothelial cells.

Matched MeSH terms: Antigens, CD

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