CIITA

class II major histocompatibility complex transactivator

Normal Function

Health Conditions Related to Genetic Changes

Bare lymphocyte syndrome type II

More than a dozen mutations in the CIITA gene have been found to cause an immune system disorder called bare lymphocyte syndrome type II (BLS II). BLS II is a type of combined immunodeficiency (CID), in which affected individuals have virtually no immune protection from foreign invaders. Consequently, individuals with BLS II have persistent infections in the respiratory, gastrointestinal, and urinary tracts, which can be life-threatening.

CIITA gene mutations involved in BLS II result in a lack of functioning CIITA protein. A shortage of CIITA to coordinate the factors that turn on MHC class II gene transcription prevents production of MHC class II proteins. Consequently, lymphocytes and other immune cells lack any MHC class II proteins on their surface, and the body has difficulty getting rid of bacteria, viruses, and fungi, leading to the persistent infections characteristic of BLS II.

More About This Health Condition

Related Conditions

Bare lymphocyte syndrome type IIAutoimmune Addison disease

Health Conditions Related to Genetic Changes

More than a dozen mutations in the CIITA gene have been found to cause an immune system disorder called bare lymphocyte syndrome type II (BLS II). BLS II is a type of combined immunodeficiency (CID), in which affected individuals have virtually no immune protection from foreign invaders. Consequently, individuals with BLS II have persistent infections in the respiratory, gastrointestinal, and urinary tracts, which can be life-threatening.

CIITA gene mutations involved in BLS II result in a lack of functioning CIITA protein. A shortage of CIITA to coordinate the factors that turn on MHC class II gene transcription prevents production of MHC class II proteins. Consequently, lymphocytes and other immune cells lack any MHC class II proteins on their surface, and the body has difficulty getting rid of bacteria, viruses, and fungi, leading to the persistent infections characteristic of BLS II.

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