title: Detection of immunoglobulin isotypes from dried blood spots.
abstract: The study was designed to determine the sensitivity and reproducibility of recovering immunoglobulin (Ig) isotypes (IgG subclasses, IgA, IgE and IgM classes) from dried blood spots (DBS), a methodologic subcomponent of the Upstate KIDS Study. A multiplexed Luminex assay was used for IgG1/2/3/4, IgA and IgM analysis; an ELISA was used for IgE. Plasma samples from de-identified patients were used to compare the Luminex assay with nephelometry, which is routinely used to quantify IgA, IgG and IgM in clinical samples. The IgE ELISA was compared to an immunofluorescence assay. Prior to evaluation of punches from newborn dried blood spots (NDBSs), recoveries of Ig from punches of cord blood DBSs (CBDBSs) vs. plasma from the same cord bloods were compared. Although the recoveries of Ig from plasma and DBSs were not comparable, which could be due to cell lysates in the DBS samples, the analyses were reproducible. Additionally, the levels of IgA, IgG2, IgG4, and IgM recovered from CBDBSs positively correlated with those in plasma. The DBS data is a relative value since it is not equivalent to the plasma concentration. The majority of Ig concentrations recovered from 108 newborns of the Upstate KIDs Study were within the range of newborn plasma Ig levels with the exception of IgG3. The IgG4 values displayed the greatest variance with a wide range (0.01-319 mg/dl), whereas, IgG1 values had the narrowest range (85.2-960.4 mg/dl).
authors: Wadsworth Center, New York State Department of Health, Albany, NY 12208, United States.
authors: Nancy J
authors: NJ
authors: Andersen
authors: Wadsworth Center, New York State Department of Health, Albany, NY 12208, United States.
authors: Tapan Kumar
authors: TK
authors: Mondal
authors: Serology/Immunology Lab, Albany Medical Center, Albany, NY 12208, United States.
authors: Mark T
authors: MT
authors: Preissler
authors: University of Colorado, ClinImmune Labs, Aurora CO 80045, United States.
authors: Brian M
authors: BM
authors: Freed
authors: University of Colorado, ClinImmune Labs, Aurora CO 80045, United States.
authors: Sabine
authors: S
authors: Stockinger
authors: University at Albany School of Public Health, Rensselaer, NY 12144, United States.
authors: Erin
authors: E
authors: Bell
authors: Congenital Malformations Registry, NYSDOH, United States.
authors: Charlotte
authors: C
authors: Druschel
authors: Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health & Human Development, United States.
authors: Germaine M Buck
authors: GM
authors: Louis
authors: Wadsworth Center, New York State Department of Health, Albany, NY 12208, United States. Electronic address: David.Lawrence@Wadsworth.org.
authors: David A
authors: DA
authors: Lawrence
mesh_terms: D059788:Dried Blood Spot Testing / Q000592:standards*; D004797:Enzyme-Linked Immunosorbent Assay; D005312:Fetal Blood / Q000737:chemistry; D005333:Fetus; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000097:blood* / Q000145:classification; D007231:Infant, Newborn; D008163:Luminescent Measurements; D009391:Nephelometry and Turbidimetry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D007132:Immunoglobulin Isotypes
keywords: Cord blood; Dried blood spots; IgE; Immunoglobulin isotypes; Newborn