The impact of growth factors on human induced pluripotent stem cells differentiation into cardiomyocytes.

Human induced pluripotent stem cells (hiPSCs) act as a promising therapeutic alternative for cardiovascular diseases. They yield a large number of functional cardiomyocytes (CMs) from autologous cell sources without ethical or immunological problems. However, significant limitations still remain in terms of line-to-line variability in CM yield and reproducibility. AIM: To efficiently enhance NP0040 hiPSCs differentiation into CMs. MAIN METHODS: Following a standard cardiac differentiation protocol using small molecules targeting the canonical Wnt signaling, growth factors (BMP4 and FGF2) and ascorbic acid were added further in order to increase the cardiac differentiation efficiency. All cultures were conducted in serum-free, feeder-free monolayer system followed by lactate purification. KEY FINDINGS: Using NP0040 hiPSCs, the CM yield resulting from modulation of the Wnt signaling pathway alone was inefficient compared to previous studies while the addition of BMP4, FGF2 and ascorbic acid resulted in enhanced cardiac differentiation outcome. The later resulted in a high yield (up to 92%) of cardiac troponin-T (cTnT) + CMs contracting spontaneously as organized sheets in 15 independent experiments. They were validated structurally and functionally using immunofluorescent staining for sarcomeric α-actinin, cTnT, MLC2v and Connexin 43. Reverse-transcriptase PCR revealed cardiac transcription factors and cardiac-specific genes expression. CMs were electrically connected to one another. Recorded action potential (AP) showed waves of relatively mature ventricular-like phenotype. SIGNIFICANCE: We demonstrated that hiPSC lines respond differently to a standard cardiac differentiation protocol and that a well-orchestrated interplay between Wnt, BMP4, FGF/MEK and Ascorbic acid MEK/ERK1/2 signaling pathways is beneficial in enhancing the differentiation outcome.

Anti-cyclic citrullinated peptide antibodies in children with Juvenile Idiopathic Arthritis.

AIM: The purpose of present study was to access the prevalence of anti-cyclic citrullinated peptide (anti-CCP) antibodies in children with Juvenile Idiopathic Arthritis (JIA), and to investigate the clinical significance and diagnostic value of the anti-CCP antibodies in correlation with age, sex & activity. METHODS: This case-control study was performed on 50 patients with JIA in addition to 40 sex and age-matched children as a control group. The participants were recruited from rheumatology Outpatient Clinic of Cairo University Specialized Pediatric Hospital. Patients were subjected to full history taking, clinical examination, routine laboratory investigations and x-rays on involved joints. Both patients and controls underwent assay of anti-CCP antibodies by AxSYM Anti-CCP IgG Microparticle Enzyme Immunoassay (MEIA) which is a semi-quantitative determination of the IgG class of autoantibodies specific to cyclic citrullinated peptide (CCP) in patients' serum or plasma. Data were analyzed using Mann-Whitney U test, ANOVA, and independent-samples t-test by SPSS version 15. RESULTS: Anti-CCP positivity was identified amongst patients with JIA, particularly those JIA patients experiencing RF positive polyarticular disease onset. Above all, it is important that anti-CCP positivity and bone erosions, degree of joint damage, and ESR levels were significantly correlated. CONCLUSION: Anti-CCP could be utilized as a valuable marker in the polyarticular form of JIA to direct early, and could be aggressive therapeutic intervention.