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Biology subjects

Dalbeth, N.

Publications and source records attributed to Dalbeth, N..

3 recordsLinked to original sources

Characterization of adult human skeletal cells in different tissues reveals a CD90+CD34+ periosteal stem cell population

Skeletal stem and progenitor cells are critical for bone homeostasis and healing, but their identity and diversity in humans are not well understood. In this study, we compared stromal populations in matched tissues from the femoral head and neck of 21 human participants using spectral flow cytometry of freshly isolated cells. High-level analysis indicated significant differences in marker distribution between periosteum, articular cartilage, endosteum and bone marrow stromal populations, and identified populations that were highly enriched or unique to specific tissues. Periosteum-enriched markers included CD90 and CD34. Articular cartilage, which has very poor regenerative potential, showed enrichment of multiple markers, including the PDPN+CD73+CD164+ population previously reported to represent human skeletal stem cells. We further characterized periosteal populations by combining CD90 with other strongly expressed markers. CD90+CD34+ cells sorted directly from periosteum showed significant colony-forming unit fibroblasts (CFU-F) enrichment, rapid expansion, and consistent multi-lineage differentiation of clonal populations. In situ, CD90+CD34+ cells include a perivascular population in the outer layer of the periosteum and non-perivascular cells closer to the bone surface. In conclusion, our study indicates considerable diversity in the stromal cell populations in different tissue compartments within the adult human skeleton, and suggests that periosteal stem cells reside within the CD90+CD34+ population.

cell biology↗

Pleiotropic effect of ABCG2 in gout: involvement in serum urate levels and progression from hyperuricemia to gout

BackgroundThe ABCG2 Q141K (rs2231142) and rs10011796 variants associate with hyperuricaemia (HU). The effect size of ABCG2 rs2231142 on urate is [~]60% that of SLC2A9, yet the effect size on gout is greater. We tested the hypothesis that ABCG2 plays a role in the progression from HU to gout by testing for association of ABCG2 rs2231142 and rs10011796 with gout using HU controls. MethodsWe analysed 1,699 European gout cases and 14,350 normourciemic (NU) and HU controls, and 912 New Zealand (NZ) Polynesian (divided into Eastern and Western Polynesian) gout cases and 696 controls. Association testing was performed using logistic and linear regression with multivariate adjusting for confounding variables. ResultsIn Europeans and Polynesians, the ABCG2 141K (T) allele was associated with gout using HU controls (OR=1.85, P=3.8E-21 and ORmeta =1.85, P=1.3E-03, respectively). There was evidence for an effect of 141K in determining HU in European (OR=1.56, P=1.7E-18) but not in Polynesian (ORmeta=1.49, P=0.057). For SLC2A9 rs11942223, the T allele associated with gout in the presence of HU in European (OR=1.37, P=4.7E-06), however significantly weaker than ABCG2 rs2231142 141K (PHet=0.0023). In Western Polynesian and European, there was epistatic interaction between ABCG2 rs2231142 and the genetically-independent rs10011796. Combining the presence of the 141K allele with the rs10011796 CC-genotype increased gout risk, in the presence of HU, 21.5-fold in Western Polynesian (P=0.009) and 2.6-fold in European (P=9.9E-06). The 141K allele positively associated with flare frequency in Polynesian (Pmeta =2.5E-03). ConclusionThese data are consistent with a role for ABCG2 141K in gout in the presence of established HU.

genetics↗

Discordant association of the CREBRF rs373863828 minor allele with increased body mass index and protection from type 2 diabetes in Maori and Pacific (Polynesian) people living in New Zealand

Aim/HypothesesThe minor allele of CREBRF rs373863828 associates with increased body mass index (BMI) and reduced risk of type 2 diabetes (T2D) in the Samoan population of Samoa and American Samoa. Our aim was to test rs373863828 for association with BMI and odds of T2D, gout and chronic kidney disease (CKD) in M[a]ori and Pacific (Polynesian) people living in Aotearoa New Zealand in 2,286 adults.\n\nMethodsAssociation analyses were performed by linear and logistic regression with BMI, log-transformed BMI, waist circumference, T2D, gout and CKD. Analyses were adjusted for age, sex, the first four genome-wide principal components, and (when appropriate) BMI, waist circumference and T2D.\n\nResultsFor the minor allele of rs373863828 the effect size for log-transformed BMI was 0.038 (95% CI [0.022-0.055], P=4.8x10-6) and for T2D was OR=0.59 (95% CI [0.47-0.73], P=1.9x10-6). There was no evidence for association of genotype with variance in BMI (P=0.13). Nor was there evidence for association with serum urate ({beta}=0.012 mmol/L, Pc=0.10), gout (OR=1.00, P=0.98) or CKD (OR=0.91, P=0.59).\n\nConclusions/interpretationOur results replicated, with very similar effect sizes, association of the minor allele of rs373863828 with higher BMI but lower odds of T2D among New Zealand Polynesian adults, as in Samoan adults living in Samoa and American Samoa.

genetics↗