Factitious transient neonatal hyperthyrotropinemia

We report an infant with abnormally elevated levels of TSH determined in the Maryland State Laboratory for Neonatal Thyroid Screening, but normal levels in three other laboratories. The TSH level in the infant normalized by six months of age. The mother, who had a history of sarcoidosis, also had factitious hyperthyrotropinemia in the Maryland State Laboratory. Gel chromatography and ammonium sulfate precipitation of maternal serum demonstrated that the factor responsible for the factitious hyperthyrotropinemia was an immunoglobulin G. Maternal TSH levels in the Maryland State Laboratory were normalized by treatment of serum with polyethylene glycol. However, protein electrophoresis, immunoglobulin levels and immunofixation electrophoresis were all normal. We conclude that a subclass of immunoglobulins G, probably resulting from sarcoidosis, interfered with the precipitation of the TSH-antibody complex in the TSH radioimmunoassay of the Maryland State Laboratory

Immunology of diabetes society T-Cell workshop: HLA class I tetramer-directed epitope validation initiative T-Cell workshop report-HLA class I tetramer validation initiative

BACKGROUND: Identification of T-cell reactivity to β-cell antigen epitopes is an important goal for studying pathogenesis and for designing and monitoring of immunotherapeutic interventions in type 1 diabetes (T1D). METHODS: We performed a multicentre validation of known human leukocyte antigen (HLA) class I CD8+ T-cell epitopes. To this end, peripheral blood T-cell responses were measured in 35 recently (<2 years) diagnosed HLA-A*02:01+ T1D patients using blind-coded HLA-A2 tetramers (TMrs) and pentamers (PMrs), encompassing two epitopes of preproinsulin (PPI; PPIA12-20 and PPIB10-18) and two epitopes of glutamic acid decarboxylase (GAD; GAD114-122 and GAD536-545). We also compared the readout of TMrs and PMrs with a CD8+ T-cell interferon-γ enzyme-linked immunospot assay. RESULTS: Despite the minute frequencies of autoreactive cells detected by TMrs/PMrs, most (73-77%) T1D patients had responses to one or more of the epitopes used. All four epitopes were recognized by T1D patients, with a prevalence ranging from 5 to 25%. TMrs and PMrs detected more positive responses to the β-cell epitopes than CD8+ T-cell interferon-γ enzyme-linked immunospot. However, concordance between positive responses to TMrs and PMrs was limited. CONCLUSIONS: Using a multicentre blind-coded setup and three different T-cell assays, we have validated PPI and GAD epitopes as commonly recognized CD8+ T-cell targets in recently diagnosed T1D patients. Both TMrs and PMrs showed higher detection sensitivity than the CD8+ T-cell interferon-γ enzyme-linked immunospot assay. However, there are some important methodological issues that need to be addressed in using these sensitive techniques for detecting low frequency responses