Severe combined immunodeficiency: From its discovery to the perspective

Area of Science:

• Immunology
• Genetics
• Pediatrics

Background:

• Severe combined immunodeficiency (SCID) impairs lymphocyte development, leading to fatal infections in infants without prompt treatment.
• SCID affects approximately 1 in 50,000 live births and is caused by various genetic defects.
• Hematopoietic stem cell transplantation (HSCT) has been a treatment for SCID since 1968.

Purpose of the Study:

• To highlight the importance of early detection of SCID in infants.
• To introduce newborn screening (NBS) for SCID as a method for early intervention.
• To emphasize the utility of T-cell receptor excision circles (TRECs) quantification for SCID NBS.

Main Methods:

• Quantification of T-cell receptor excision circles (TRECs) using quantitative PCR.
• TRECs are measured from DNA samples, such as Guthrie cards.
• TRECs are circular DNA fragments generated during T-cell receptor rearrangement.

Main Results:

• SCID patients characteristically lack TRECs.
• TRECs quantification is a reliable method for SCID newborn screening.
• NBS for SCID is implemented in most of the United States.

Conclusions:

• Early detection of SCID through NBS significantly increases survival rates.
• Implementing TRECs quantification for NBS in Japan is crucial to save affected children.
• Advancing SCID diagnosis and treatment through newborn screening is essential for improving pediatric health outcomes.