Ronald Bellisario

Simultaneous measurement of antibodies to three HIV-1 antigens in newborn dried blood-spot specimens using a multiplexed microsphere-based immunoassay

We developed a fluorescent immunoassay to simultaneously measure antibodies to three HIV-1 antigens from newborn dried blood-spot specimens. The multiplexed assay uses fluorescent microspheres and a flow analyzer. The procedure is sensitive, precise and accurate, and can be expanded to simultaneously measure additional multiple analytes from a single specimen.

Measurement of Serum Alpha-Fetoprotein in Early Infancy: Utilization of Dried Blood Specimens

Summary: Serum alpha-fetoprotein (AFP) concentrations were measured in dried blood spots and the biologic half-life of AFP was determined during the first month after parturition. AFP Mood levels, in babies at all birthweight groups during the first wk, were partitioned according to birthweight and sex. A synthetic surge of serum AFP at postnatal day 3 was observed in babies of the low birthweight category (<6 Ib 8 oz), whereas a concomitant surge could not be demonstrated in babies of medium, (6 Ib 8 oz to 8 Ib 8 oz), and high birthweight, (>8 Ib 8 oz), categories. All babies weighing less than 6 Ib 8 oz, regardless of prematurity likewise displayed the synthetic surge. The sex of the infant appeared to have no influence on AFP serum concentrations. In a population of infants ranging in age from 1–30 days, the biologic apparent half-life of AFP was calculated as 5.7 days; however, the half-life of AFP was found to differ among the three groups of infants when subdivided by birthweight and was higher (7.7 days) in babies of low birthweight. Our determination of 2 S.D. cutoff values for AFP in the first wk of life should prompt further studies in which the relationship of AFP to newborn disorders should be more fully explored.

Newborn screening for hemoglobinopathies using a rapid automated membrane convective liquid chromatography system

Abstract Membrane convective liquid chromatography (MCLC) is a new approach to the high-speed, high-resolution separation of biomolecules. The practical application of MCLC for the screening; of newborn hemoglobinopathies by testing dried blood specimens was examined. Hemoglobins F, A, S, C, D, E and O Arab were separated in 3 min by cation-exchange MCLC. Parallel studies comparing the automated, computer-driven MCLC system to the methods (cellulose acetate/citrate agar electrophoresis and isoelectric focusing) currently used in the New York State newborn screening laboratory were analyzed in terms of precision, accuracy, and sensitivity of hemoglobin variant detection and subsequent data management.