Newborn Screening for Severe T and B Cell Lymphopenia Using TREC/KREC Detection: A Large-Scale Pilot Study of 202,908 Newborns

• Published in: Journal of clinical immunology 2024-04, Vol.44 (4), p.93-93, Article 93
• Main Authors: Marakhonov, Andrey V., Efimova, Irina Yu, Mukhina, Anna A., Zinchenko, Rena A., Balinova, Natalya V., Rodina, Yulia, Pershin, Dmitry, Ryzhkova, Oxana P., Orlova, Anna A., Zabnenkova, Viktoriia V., Cherevatova, Tatiana B., Beskorovainaya, Tatiana S., Shchagina, Olga A., Polyakov, Alexander V., Markova, Zhanna G., Minzhenkova, Marina E., Shilova, Nadezhda V., Larin, Sergey S., Khadzhieva, Maryam B., Dudina, Ekaterina S., Kalinina, Ekaterina V., Mudaeva, Dzhaina A., Saydaeva, Djamila H., Matulevich, Svetlana A., Belyashova, Elena Yu, Yakubovskiy, Grigoriy I., Tebieva, Inna S., Gabisova, Yulia V., Irinina, Nataliya A., Nurgalieva, Liya R., Saifullina, Elena V., Belyaeva, Tatiana I., Romanova, Olga S., Voronin, Sergey V., Shcherbina, Anna, Kutsev, Sergey I.
• Format: Article
• Language: English
• Subjects: Agammaglobulinemia; B-lymphocytes; Biomedical and Life Sciences; Biomedicine; DNA; early diagnosis; excision; Flow cytometry; Genetic disorders; Humans; Immune system; Immunology; immunosuppression; Infant; Infant, Newborn; Infants; Infectious Diseases; Internal Medicine; Lymphocytes B; Lymphocytes T; Lymphopenia; Lymphopenia - diagnosis; Medical Microbiology; Medical screening; Neonatal Screening - methods; Neonates; Newborn babies; Pilot Projects; prognosis; Receptors, Antigen, T-Cell - genetics; Russia; Severe combined immunodeficiency; Severe Combined Immunodeficiency - diagnosis; Severe Combined Immunodeficiency - genetics; T cell receptors; T-Lymphocytes; trisomics; Trisomy; Whole genome sequencing
• ISSN: 0271-9142; 1573-2592; 1573-2592
• DOI: 10.1007/s10875-024-01691-z

Newborn screening (NBS) for severe inborn errors of immunity (IEI), affecting T lymphocytes, and implementing measurements of T cell receptor excision circles (TREC) has been shown to be effective in early diagnosis and improved prognosis of patients with these genetic disorders. Few studies conducted on smaller groups of newborns report results of NBS that also include measurement of kappa-deleting recombination excision circles (KREC) for IEI affecting B lymphocytes. A pilot NBS study utilizing TREC/KREC detection was conducted on 202,908 infants born in 8 regions of Russia over a 14-month period. One hundred thirty-four newborns (0.66‰) were NBS positive after the first test and subsequent retest, 41% of whom were born preterm. After lymphocyte subsets were assessed via flow cytometry, samples of 18 infants (0.09‰) were sent for whole exome sequencing. Confirmed genetic defects were consistent with autosomal recessive agammaglobulinemia in 1/18, severe combined immunodeficiency – in 7/18, 22q11.2DS syndrome – in 4/18, combined immunodeficiency – in 1/18 and trisomy 21 syndrome – in 1/18. Two patients in whom no genetic defect was found met criteria of (severe) combined immunodeficiency with syndromic features. Three patients appeared to have transient lymphopenia. Our findings demonstrate the value of implementing combined TREC/KREC NBS screening and inform the development of policies and guidelines for its integration into routine newborn screening programs.