def METHOD_NAME(self, adata: AnnData) -> dict:
    """Register the field."""
    state_registry = super().METHOD_NAME(adata)
    if self.use_batch_mask:
        batch_mask = self._get_batch_mask_protein_data(adata)
        if batch_mask is not None:
            state_registry[self.PROTEIN_BATCH_MASK] = batch_mask
    return state_registry