Question: when do white blood cells exit the vascular system
[{'answer': 'the innate immune response', 'provenance': [{'wikipedia_id': '11115752', 'title': 'Leukocyte extravasation', 'start_paragraph_id': 1, 'start_character': 163, 'end_paragraph_id': 1, 'end_character': 189, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '11115752', 'title': 'Leukocyte extravasation', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 363, 'bleu_score': 0.8318835444988091, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11465555762677912039}, 'section': 'Section::::Abstract.'}]}]