This may cause reactions to be weaker in the first tubes than in higher dilutions and is believed to be caused by an antibody excess in which all antigenic sites are sensitized with antibody leaving none free to form cross-links (Table 3-2).
| Serum dilution | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1:1 | 1:2 | 1:4 | 1:8 | 1:16 | 1:32 | 1:64 | 1:128 | 1:256 | 1:512 | Titre | |
| Sample #1 | 4+ | 3+ | 3+ | 2+ | 1+ | 1+ | -- | -- | -- | -- | 32 |
| Sample #2 | -- | -- | 3+ | 4+ | 4+ | 3+ | 3+ | 2+ | 1+ | -- | 256 |
* Sample 2 is an example of the prozone phenomenon
|
| Prozone Phenomenon |