Since CD3(+) CD4(+) CD45RA(+) CD45RO(-) CD31(+) RTE are reported to be TCR diverse and to contain regulatory T cells, we found it important to report that continuously reduced numbers of CD3(+) CD4(+) CD45RA(+) CD45RO(-) CD31(+) RTE, in the context of CHD7 haploinsufficiency and despite severe lymphopenia, is consistent with an uneventful clinical outcome.
The phenotype is usually T-B+NK+ SCID with lymphopenia where the clinical findings may be mild (CD3γ) or severe (CD3δ, ε, ζ) owing to the underlying molecular defect.
A mutation of human UNC119 impairs LCK activation and is associated with inadequate signaling, diminished T cell responses to TCR stimulation, CD4 lymphopenia, and infections of viral, bacterial, and fungal origin.
Numerous deleterious mutations occurring in the ADA gene have been found in patients with profound lymphopenia (T<sup>-</sup> B<sup>-</sup> NK<sup>-</sup>), thus underscoring the importance of functional purine metabolism for the development of the immune defense.
Genetic deficiency of adenosine deaminase (ADA) can cause profound lymphopenia and result in the clinical presentation of severe combined immune deficiency (SCID).
Genetic deficiencies in the purine catabolic enzyme adenosine deaminase (ADA) in humans results primarily in a severe lymphopenia and immunodeficiency that can lead to the death of affected individuals early in life.
Deficiency in the enzyme adenosine deaminase (ADA) in humans manifests primarily as severe lymphopenia and immunodeficiency, resulting in death by 6 months of age, if untreated.
The adenosine-deaminase-deficient patients highlight a treatable cause of HIV-negative CD4+ lymphopenia in adults, perhaps accounting for further cases of 'non-HIV AIDS'.
Deficiency of ADA caused the most profound lymphopenia; gamma c or Jak3 deficiency resulted in the most B cells and fewest natural killer (NK) cells; NK cells and function were highest in autosomal recessive and unknown types of SCID.
Two sisters who noted recurrent, predominantly chest infections in their twenties were found in their thirties to have CD4+ lymphopenia and lymphocyte ADA activity of approximately 5% of the lower limit of normal.