And measured using the ImageJ program (NIH, http://rsb.info.nih.gov/nih-image/) [25].Neurological EvaluationNeurological functions were evaluated by the following modified scoring system: 0, no observable neurological deficits (normal); 1, failure to extend forepaw when entire body is lifted by tail (mild); 2, circling to contralateral side (moderate); and 3, loss of walking or righting reflex (severe) [26]. Three mice were tested in each group, and each mouse was subjected to 3 rounds of each test. The observers of the behavioral tests were blinded to the treatment groups, and mice of the various groups were randomized during a given testing period.Human Physiological HSP27 PreparationHeparinized human peripheral blood (40 mL) was obtained from two normal control subjects and separated by density gradient centrifugation in Lympholyte-H (Cedarlane Laboratories Ltd., Hornby, Ontario, Canada) according to the manufacturer’s instructions. Cells were lysed in lysis buffer (50 mmol/L Tris-HCl, pH 7.5, 150 mmol/L NaCl, 5 mmol/L EDTA, 0.5 sodium deoxycholate, and 0.1 mmol/L phenylmethylsulfonyl fluoride) with a Dounce homogenizer, and the lysate was centrifuged at 10,0006g for 1 h. The supernatant was applied to an Epigenetics HSP27-N1 antibody affinity column, and the column was washed with lysis buffer. HSP27 was eluted by peptide antigen (10 mg/mL) for the HSP27-N1 antibody. The eluate was further applied to an HSP27C1 antibody affinity column, and the column was washed with lysis buffer. HSP27 was eluted by a 10-mg/mL excess amount of HSP27-C1 antibody peptide antigen. HSP27 was separated from the peptide with Amicon Ultra-10 centrifugal filter units (Millipore, Billerica, MA, USA). The purity of the hHSP27 protein was over 95 . The investigation conforms to the principles outlined in the Declaration of Helsinki, and was reviewed and approved by the Juntendo University Ethics Committee. Written informed consent was obtained from all participants.hHSP27 and HSP27 Antibody, HSP27 Elution Peptide Administration or Recombinant HSP27 AdministrationMice received intravenous injections of 50 mg of hHSP27 mixed with 50 or 500 mg of HSP27-N1 or -C1 antibody 1 h after reperfusion (n = 3 in each group), 5 or 50 mg of HSP27-N1 and C1 peptides, which were used in the elution, intravenously 1 h after reperfusion (n = 3 in each group), or 50 mg of recombinant HSP27 (rHSP27; Acris Antibodies GmbH) 1 h after reperfusion (n = 3).Dephosphorylated hHSP27 Epigenetic Reader Domain AdministrationhHSP27 was dephosphorylated by active recombinant protein phosphatase 2A (Millipore) [16]. Mice received intravenous injections of 50 mg of dephosphorylated hHSP27 1 h after reperfusion (n = 3).Identification of Transition in Brain Parenchyma by Intravenous hHSP27 InjectionhHSP27 was conjugated with fluorescein isothiocyanate (FITC) according to the manufacturer’s protocol (KPL, Inc.). Mice were administered 50 mg 1317923 of FITC-hHSP27 intravenously 1 h after reperfusion and anesthetized with pentobarbital 30 min after the injection. Their brains were immediately removed, soaked in Tissue-TekH OCTTM Compound (SAKURA, Netherland), and frozen on liquid nitrogen. Coronal sections (20 mm) were cut on a cryostat (CM 1900, Leica Biosystems Nussloch GmbH, Nussloch, Germany). The sections were immediately, or after incubation with Alexa FluorH 555 Conjugated anti-NeuN antibody (Millipore), mounted with Vectashield mounting medium (VectorMS/MS Identification of hHSPhHSP27 was separated by native or SDS-polyacrylamide gel.And measured using the ImageJ program (NIH, http://rsb.info.nih.gov/nih-image/) [25].Neurological EvaluationNeurological functions were evaluated by the following modified scoring system: 0, no observable neurological deficits (normal); 1, failure to extend forepaw when entire body is lifted by tail (mild); 2, circling to contralateral side (moderate); and 3, loss of walking or righting reflex (severe) [26]. Three mice were tested in each group, and each mouse was subjected to 3 rounds of each test. The observers of the behavioral tests were blinded to the treatment groups, and mice of the various groups were randomized during a given testing period.Human Physiological HSP27 PreparationHeparinized human peripheral blood (40 mL) was obtained from two normal control subjects and separated by density gradient centrifugation in Lympholyte-H (Cedarlane Laboratories Ltd., Hornby, Ontario, Canada) according to the manufacturer’s instructions. Cells were lysed in lysis buffer (50 mmol/L Tris-HCl, pH 7.5, 150 mmol/L NaCl, 5 mmol/L EDTA, 0.5 sodium deoxycholate, and 0.1 mmol/L phenylmethylsulfonyl fluoride) with a Dounce homogenizer, and the lysate was centrifuged at 10,0006g for 1 h. The supernatant was applied to an HSP27-N1 antibody affinity column, and the column was washed with lysis buffer. HSP27 was eluted by peptide antigen (10 mg/mL) for the HSP27-N1 antibody. The eluate was further applied to an HSP27C1 antibody affinity column, and the column was washed with lysis buffer. HSP27 was eluted by a 10-mg/mL excess amount of HSP27-C1 antibody peptide antigen. HSP27 was separated from the peptide with Amicon Ultra-10 centrifugal filter units (Millipore, Billerica, MA, USA). The purity of the hHSP27 protein was over 95 . The investigation conforms to the principles outlined in the Declaration of Helsinki, and was reviewed and approved by the Juntendo University Ethics Committee. Written informed consent was obtained from all participants.hHSP27 and HSP27 Antibody, HSP27 Elution Peptide Administration or Recombinant HSP27 AdministrationMice received intravenous injections of 50 mg of hHSP27 mixed with 50 or 500 mg of HSP27-N1 or -C1 antibody 1 h after reperfusion (n = 3 in each group), 5 or 50 mg of HSP27-N1 and C1 peptides, which were used in the elution, intravenously 1 h after reperfusion (n = 3 in each group), or 50 mg of recombinant HSP27 (rHSP27; Acris Antibodies GmbH) 1 h after reperfusion (n = 3).Dephosphorylated hHSP27 AdministrationhHSP27 was dephosphorylated by active recombinant protein phosphatase 2A (Millipore) [16]. Mice received intravenous injections of 50 mg of dephosphorylated hHSP27 1 h after reperfusion (n = 3).Identification of Transition in Brain Parenchyma by Intravenous hHSP27 InjectionhHSP27 was conjugated with fluorescein isothiocyanate (FITC) according to the manufacturer’s protocol (KPL, Inc.). Mice were administered 50 mg 1317923 of FITC-hHSP27 intravenously 1 h after reperfusion and anesthetized with pentobarbital 30 min after the injection. Their brains were immediately removed, soaked in Tissue-TekH OCTTM Compound (SAKURA, Netherland), and frozen on liquid nitrogen. Coronal sections (20 mm) were cut on a cryostat (CM 1900, Leica Biosystems Nussloch GmbH, Nussloch, Germany). The sections were immediately, or after incubation with Alexa FluorH 555 Conjugated anti-NeuN antibody (Millipore), mounted with Vectashield mounting medium (VectorMS/MS Identification of hHSPhHSP27 was separated by native or SDS-polyacrylamide gel.