Rabbit Anti-ABCF1 monoclonal antibody, clone TO18-23

Objective: To investigate whether a conserved HLA class I region influenced the development of Graves' ophthalmopathy (GO) in patients with Graves' disease (GD) in a Taiwan-Chinese population. Design: Case-control study. Participants: Four hundred sixty-eight Taiwan-Chinese patients with GD; 200 of these patients had GO, whereas 268 patients did not. Methods: Five single nucleotide polymorphisms (SNPs) between the HLA-A and HLA-C loci were genotyped. Main Outcome Measures: The Mann-Whitney U test and chi-square test with Bonferroni correction were used. The odds ratios (ORs) were estimated by applying unconditional logistic regression with a 95% confidence intervals (CIs). Results: Strong gender effects on the distribution of the SNPs were apparent: male GD patients carrying an A allele at rs2074503 in the PRR3 gene tended to avoid demonstrating GO (P = 0.008; OR, 0.450; 95% CI, 0.248-0.819), whereas female patients tended to show GO (P = 0.01; OR, 1.486; 95% CI, 1.098-2.012). In addition, only the female GD patients with a T allele at rs1264439 in the ABCF-1 gene tended to demonstrate GO (P = 0.005; OR, 1.539; 95% CI, 1.139-2.081). Analysis of the haplotype blocks of the SNPs rs2074505 (GNL1) and rs2074503 (PRR3) showed that haplotype HA1 was underrepresented in male GO patients (P = 0.004; OR, 0.418; 95% CI, 0.228-0.767), whereas HA-4 was underrepresented in female GO patients (P = 0.007; OR, 0.660; 95% CI, 0.490-0.895). Conclusions: The results suggested that SNPs at PRR3 and ABCF1 genes and the haplotype composed by SNPs at GNL1 and PRR3 between the HLA-A and HLA-C genes tended to predict GO in a gender-dependent manner in patients with GD in Taiwan. (C) 2014 by the American Academy of Ophthalmology.

Human ATP-binding cassette (ABC) transporters comprise a family of 48 membrane-spanning transport proteins, many of which are associated with genetic diseases or multidrug resistance of cancers. In this study, we present a comprehensive approach for the cloning, expression, and purification of human ABC transporters in the yeast Pichia pastoris. We analyzed the expression of 25 proteins and demonstrate that 11 transporters, including ABCC3, ABCB6, ABCD1, ABCG1, ABCG4, ABCG5, ABCG8, ABCE1, ABCF1, ABCF2, and ABCF3, were expressed at high levels comparable to that of ABCB1 (P-glycoprotein). As an example of the purification strategy via tandem affinity chromatography, we purified ABCC3 (MRP3) whose role in the transport of anticancer drugs, bile acids, and glucuronides has been controversial. The yield of ABCC3 was 3.5 mg/100 g of cells in six independent purifications. Purified ABCC3, activated with PC lipids, exhibited significant ATPase activity with a V-max of 82 +/- 32 nmol min(-1) mg(-1). The ATPase activity was stimulated by bile acids and glucuronide conjugates, reaching 170 +/- 28 nmol min(-1) mg(-1), but was not stimulated by a variety of anticancer drugs. The glucuronide conjugates ethinylestradiol-3-glucuronide and 17 beta-estradiol-17-glucuronide stimulated the ATPase with relatively high affinities (apparent K-m values of 2 and 3 mu M, respectively) in contrast to bile acids (apparent K-m values of > 130 mu M), suggesting that glucuronides are the preferred substrates for this transporter. Overall, the availability of a purification system for the production of large quantities of active transporters presents a major step not only toward understanding the role of ABCC3 but also toward future structure-function analysis of other human ABC transporters.