International collaborative study to evaluate and calibrate two recombinant L chain Ferritin preparations for use as a WHO International Standard

Objectives To evaluate and calibrate two candidate preparations for the 4th International Standard for Ferritin (Human, Recombinant) (codes: 19/118 and 19/162) against the 3rd International Standard for Ferritin (Human, Recombinant) (code: 94/572), and three serum commutability samples in an international collaborative study involving 12 laboratories in nine countries. Methods Eleven of the 12 participating laboratories performed Ferritin quantitation using automated assay platforms and one laboratory used a manual ELISA kit. Results There was better overall agreement between all laboratories and between assay methods for the potency of preparation 19/118 than for preparation 19/162. The overall geometric mean potency (from all methods) of the candidate 4th International Standard, 19/118, was 10.5 µg/ampoule, with inter-laboratory variability, expressed as % geometric coefficient of variation (GCV), of 4.7%. Accelerated stability studies have predicted both 19/118 and 19/162 to be very stable for long term storage at −20 °C. Conclusions The candidate 4th International Standard for Ferritin (Human, Recombinant) (19/118) has been shown to be immunologically similar to the 3rd International Standard for Ferritin (Human, Recombinant) (94/572). It was recommended to and accepted by the WHO Expert Committee on Biological Standardization that 19/118 be established as the 4th International Standard for Ferritin (Human, Recombinant) with an assigned potency of 10.5 µg/ampoule and expanded uncertainty limits 10.2–10.8 µg/ampoule (95% confidence; k=2.23).

Novel Genetic and Cognitive Findings From the Long Life Family Study

The Long Life Family Study (LLFS), funded by the National Institute on Aging, is an international collaborative study of the genetics and familial components of exceptional longevity and healthy aging. We phenotyped 4,953 individuals from 539 two-generational families (1,727 proband; 3,226 offspring) at baseline (2006-2009). A second visit (2014-2017) was conducted for 2,904 (478 proband; 2,426 offspring) participants. The longitudinal, comprehensive in-person visits measured domains of healthy aging, including physical performance, cognition, and blood markers. Extensive genetic analyses were performed using the baseline blood draw, including genotyping with the Illumina 2.5M Human Omni array, linkage analyses with the families, whole genome sequencing using the TopMED protocol, and metabolomic assays. Collectively, this symposium will present novel findings that elucidate new potential genes and genetic interactions, investigate metabolomics profiles among APOE4 carriers, and refine phenotypic cognition definitions. Specifically, Dr. Santanasto will share results flanking the mesothelin gene associated with longitudinal gait speed. Then, Dr. An will share his findings of a new intronic variant in PKD1L2 gene associated with adiponectin, a marker of insulin resistance. Next, Dr. Arbeev will discuss genetic interactions between candidate genes for physiologic dysregulation and candidate genes for Alzheimer’s disease (AD, UNC5C gene). Ms. Yao will examine metabolomic profile differences between APOE4 carriers who develop AD and those who do not. Lastly, Mr. Xiang will introduce a method for combining multiple cognitive tests into a more sensitive overall cognitive score. As Discussant, Dr. Evan Hadley will share insights and propose future directions for LLFS.