Table 2.
Patterns of DSA found in pretransplant sera (n = 156).
| Bead type | DSA pattern of reactivity |
||||||
|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | |
| SAB | + | + | + | − | + | − | − |
| iBead | + | + | − | + | − | + | − |
| Denatured | + | − | + | + | − | − | + |
| Total no. found | 53 | 99 | 28 | 10 | 61 | 25 | 63 |
The presence of donor-specific human leucocyte antigen (HLA) antibodies (DSA) was defined according to reactivity against single antigen bead (SAB), iBeads or beads with denatured HLA. The presence or absence of reactivity against a specific type of bead is indicated by a + or − sign leading to seven patterns of reactivity against the three bead preparations. Each DSA from each serum was counted. Pattern 1 occurs when antibodies react with both intact and denatured HLA, patterns 2 and 6 represent antibodies recognizing only intact HLA, patterns 3 and 7 are considered as reactivity towards denatured HLA only, the specificity of antibodies yielding pattern 4 is unclear and discussed separately, whereas pattern 5 probably arises from low levels of antibodies against intact HLA. In the table are the actual DSA numbers found per pattern of reactivity in 156 sera.