Table 1.
Clinical history and immune phenotyping of patients A and B, and additional studies on family members.
| Patient A (<1 mo) | Patient B (9 mo) | Reference range | ||
|---|---|---|---|---|
| Clinical presentation at time of lab evaluation | asymptomatic | PJP pneumonia on steroids | ||
| Phenotype of SCID variant | T−/B+/NKlow | T+(CD8low)/B+/NKlow | ||
| TREC (copies/microliter) at birth* | 0 (L*) | 0 (L*) | >15 [Patient A NBS in Florida], > 252 [Patient B NBS Massachusetts] |
|
| Absolute lymphocyte (cells/μL) | 669 (L) | 1,596 (L) | >2,600 | |
| Absolute CD3 T (cells/μL) | 9 (L) | 1,062 (L) | >1,600 | |
| Absolute CD4 T (cells/μL) | 9 (L) | 1,043 | >1,000 | |
| Absolute CD8 T (cells/μL) | 7 (L) | 27 (L) | >400 | |
| Absolute CD19 B (cells/μL) | 450 (L) | 365 (L) | >600 | |
| Absolute CD56 NK (cells/μL) | 61 (L) | 145 (L) | >200 | |
| CD4+CD45RA+ naïve T (cells/μL), (% of total CD4) | 1 (11%) (L) | 0 (L) | >50% of total CD4 | |
| CD8+CD45RA+ naïve T (cells/μL), (% of total CD8) | 2 (30%) (L) | 0 (L) | >50% of total CD8 | |
| CD3+ T cell proliferation to mitogens | PHA | 0.9% (L) | 7.1% (L) | >58.4% |
| PWM | 11.5% | 4.1% | >3.4% | |
| T cell proliferation with interleukins | anti-CD3 | |||
| anti-CD3/CD28 | n.a. | Absent | ||
| anti-CD3/IL-2 | ||||
| CD132 (common γ chain) expression | T cells | n.a. | 84% (L) | >99% |
| B cells | 87% | 84% | >58% | |
| NK cells | 71% (L) | 66% (L) | >84% | |
| CD132 signaling | absent | absent | ||
| X chromosome inactivation (XCI) in carriers | ||||
| Mother | PBMC | 76:24 | 85:15 (H) | <80:20 |
| Mother | T cells | 100:0 (H) | 100:0 (H) | <80:20 |
| 13-year-old sister | PBMC | 90:10 (H) | n.a. | <80:20 |
| 14-year-old sister | PBMC | 91:9 (H) | n.a. | <80:20 |
X-inactivation studies on peripheral blood mononuclear cells (PBMCs) were performed by Greenwood Genetics (Greenwood, SC). This study does not allow for distinguishing wild type (wt) or mutant alleles. X-inactivation studies in T cells at the NIH allowed for distinction between wt and mutant alleles (Figure 2A). *From NBS card. L indicates low, H indicates high. PJP: Pneumocystis jirovecii pneumonia.