title: Immune cells subpopulations in cerebrospinal fluid and peripheral blood of patients with Aneurysmal Subarachnoid Hemorrhage.
abstract: BACKGROUND
  There is growing evidence supporting the role of inflammation in aneurysmal subarachnoid hemorrhage (aSAH) pathophysiology and it is of great interest to elucidate which immune mechanisms are involved.
  
  
  METHODS
  12 aSAH patients and 28 healthy controls were enrolled prospectively. We assessed leukocytes subpopulations and their activation status by flow cytometry in cerebrospinal fluid (CSF) and peripheral blood (PB) of SAH patients at the same time and in PB of controls.
  
  
  RESULTS
  Monocytes and neutrophils were activated in CSF of aSAH patients. The percentage of CD14(++)CD16(+) monocytes were higher in CSF than in PB of aSAH patients, and were also increased in PB of aSAH patients compared with controls. An enhanced expression of CD69 was shown in CSF neutrophils compared with PB in aSAH patients. PB of aSAH patients showed lower percentage of total lymphocytes compared with controls PB. Additionally, lymphocytes were activated in CSF and PB of aSAH patients. CD4(+) and CD8(+) T cells had a decreased expression on CD3 and higher levels of CD69 in CSF compared with PB in aSAH patients. Moreover, PB CD4(+) and CD8(+) T cells of aSAH patients were activated compared with controls. Additionally, CD28 expression was decreased on CSF T lymphocytes.
  
  
  CONCLUSIONS
  Our data suggest an important recruitment of leukocytes to the site of injury in aSAH as well as an increased activation at this level. Overall, these results indicate that aSAH probably stimulates both the innate and adaptive immune responses.
authors.affiliation: Cátedra de Medicina Intensiva. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.|Cátedra de Hematología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Avda. Italia s.n, CP 11300 Montevideo, Uruguay.
authors.forename: Leandro
authors.initials: L
authors.lastname: Moraes
authors.affiliation: Cátedra de Hematología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Avda. Italia s.n, CP 11300 Montevideo, Uruguay.|Departamento Básico de Medicina, Hospital de Clínicas, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
authors.forename: Sofía
authors.initials: S
authors.lastname: Grille
authors.affiliation: Cátedra de Medicina Intensiva. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
authors.forename: Paula
authors.initials: P
authors.lastname: Morelli
authors.affiliation: Departamento de Cardiología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
authors.forename: Rafael
authors.initials: R
authors.lastname: Mila
authors.affiliation: Cátedra de Hematología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Avda. Italia s.n, CP 11300 Montevideo, Uruguay.
authors.forename: Natalia
authors.initials: N
authors.lastname: Trias
authors.affiliation: Cátedra de Hematología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Avda. Italia s.n, CP 11300 Montevideo, Uruguay.
authors.forename: Andreína
authors.initials: A
authors.lastname: Brugnini
authors.affiliation: Departamento de Cardiología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
authors.forename: Natalia
authors.initials: N
authors.lastname: LLuberas
authors.affiliation: Cátedra de Medicina Intensiva. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
authors.forename: Alberto
authors.initials: A
authors.lastname: Biestro
authors.affiliation: Cátedra de Hematología. Hospital de Clínicas. Facultad de Medicina, Universidad de la República, Avda. Italia s.n, CP 11300 Montevideo, Uruguay.
authors.forename: Daniela
authors.initials: D
authors.lastname: Lens
keywords: Aneurysmal subarachnoid hemorrhage; Cerebrospinal fluid; Flow cytometry; Neuroinflammation; Systemic inflammation