Clinical And Molecular Characteristics Of ALPS And Digeorge Syndrome

Part one:Clinical and molecular characteristics of an ALPS patient with NRAS gene mutationObjective:To investigate the clinical features, genetic characteristics and immunological alterations of a patient with NRAS mutation causing autoimmune lymphoproliferative syndrome (ALPS).Method:The present study enrolled a 28-month-old girl who presented with recurrent fever, chronic hepatosplenomegaly, lymphadenopathy, hyperleukocytosis and mild autoimmune cytopenia. Sequencing of NRAS gene fragments were amplified and sequenced. Flow cytometry technology was used to analyze NRAS protein. DiversityTCR-Vβ, proliferation of T lymphocyte were assessed. Subsets of white blood cells such as CD4+CD197+, CD4+CD45RO+, CD8+CD197+CD45RO-, CD8+CD197-CD45RO-, CD19+CD27-, CD19+CD27+ and CD 14+, were separated by flow cytometry and mutation of NRAS in these individual populations were analyzed.Resμlts:Sequencing of the patient’s NRAS gene revealed a heterozygote mutation (c.289G>C, p.G12A), with which the parents were normal. TCR-Vβ diversity was not limited. The number of abnormal lymphocyte subsets and the lymphocyte proliferation suggested the dysfunction of T cells function. After being TA cloned, different populations of white blood cells showed different frequency of mutated genotype of NRAS gene, indicating that the mutation of NRAS mainly occurred in neutrophils and monocytes. T cells did not show mutation of NRAS, and B cells showed very low mutation rate.Conclusion:The present study identified the first patient with ALPS caused by NRAS mutation in mainland China. It’s important for physicians to realize that patient with ALPS had varied clinical and immunophenotyping. Prompt diagnosis is necessary for appropriate management.Part two:Clinical and immunological analysis of a Chinese boy with atypical complete DiGeorge syndromeObjective:To investigate the clinical features and immunological of a patient with atypical complete DiGeorge syndrome, providing suggestions for diagnosis.Method:This study enrolled a 7-year-old boy who presented with recurrent infection, abnormal facial. Flow cytometry technology were used to analyze T, B cell subsets, CFSE labeling analysis of T cell proliferation, CDR3 scanning spectral type of technical analysis of TCR diversity, quantitative PCR analysis of TRECs。Resplts:Analysis of T, B lymphocyte subsets showed that T lymphocytes was significantly reduced, naive T cells<50/mm3, memory B lymphocytes slightly reduced, CFSE proliferation suggested the dysfunction of T cells proliferation. TCR-V β subfamily showed monoclonal or oligoclonal. Quantitative PCR was not detected TRECs content.Conclusion:The present study identified the first patient with atypical complete DiGeorge syndrome in China. It’s important for physicians to realize that patient with DiGeorge syndrome had varied clinical and immunophenotyping. Prompt diagnosis necessary for appropriate management.