title: Novel inflammatory biomarkers and their correlation to Chlamydia pneumoniae titres in acute ischemic stroke.
abstract: BACKGROUND
  Young stroke patients constitute 15%-30% of all stroke patients in India as against 3.0%-8.5% reported from the West. The mechanisms for stroke in the young may include unconventional risk factors such as infections. We aimed to investigate the role (if any) of Chlamydia pneumoniae antibodies in young patients with acute ischemic stroke (AIS). Several proinflammatory cytokines and biomarkers are released early after the onset of brain ischemia. We assessed the role of heat shock protein (hsp) 65, neopterin, and myeloperoxidase upregulation after AIS in predicting stroke severity. We also assessed relationship of upregulated inflammatory biomarkers with C pneumoniae antibody titres (IgG, IgA, and IgM).
  
  
  METHODS
  Eighty acute stroke patients and healthy age- and sex-matched controls were recruited. Blood samples were drawn within 1 week from the onset of stroke. Detection of IgA, IgG, and IgM antibodies to C pneumoniae was done with a validated microimmunofluorescence technique from 5 mL of serum in all subjects. Inflammatory biomarkers such as neopterin, myeloperoxidase and hsp 65 were estimated with sandwich enzyme linked immunosorbent assay (ELISA) method.
  
  
  RESULTS
  hsp 65 and neopterin were significantly elevated in all stroke patients with respect to healthy controls (odds ratio [OR], 4.9; 95% confidence interval [CI], 23.5-67.8; P = .001 and OR, 4.4; 95% CI, 2.08-9.4; P = .04, respectively). Eighty-one percent of cases were seropositive for IgA versus 32% of controls (P = .003), and IgG was positive in 52.7% versus 17.3% of controls (P = .05). Myeloperoxidase levels were similar in patients and controls. Correlation and multiple regression indicated a high level of predictability and sensitivity of hsp 65 to IgA. C. pneumoniae antibody titres when all other variables were constant (F [4,90] = -6.8, P = .001). Patients with high NIHSS scores (>15) had elevated levels of hsp 65 (mean, 13.2 ng/mL) suggesting correlation with stroke severity.
  
  
  CONCLUSIONS
  The study demonstrated high levels of hsp 65 and neopterin levels in AIS correlated to significantly elevated IgA titres of C pneumoniae. Elevated levels of hsp 65 were associated with stroke severity.
authors.affiliation: Department of Neurology, AIIMS, New Delhi, India. Electronic address: vasanthapadma123@gmail.com.
authors.forename: M V Padma
authors.initials: MV
authors.lastname: Srivastava
authors.affiliation: Department of Neurology, AIIMS, New Delhi, India.
authors.forename: Ashu
authors.initials: A
authors.lastname: Bhasin
authors.affiliation: Department of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Rama
authors.initials: R
authors.lastname: Chaudhry
authors.affiliation: Department of Neurology, AIIMS, New Delhi, India.
authors.forename: Sakshi
authors.initials: S
authors.lastname: Sharma
authors.affiliation: Department of Neurobiochemistry, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Vivekanandhan
authors.initials: V
authors.lastname: Subbaiah
authors.affiliation: Department of Neurology, AIIMS, New Delhi, India.
authors.forename: Rohit
authors.initials: R
authors.lastname: Bhatia
authors.affiliation: Department of Neurology, AIIMS, New Delhi, India.
authors.forename: Manjari
authors.initials: M
authors.lastname: Tripathi
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial; D015415:Biomarkers / Q000097:blood*; D002545:Brain Ischemia / Q000097:blood*; D016022:Case-Control Studies; D002690:Chlamydia Infections / Q000097:blood*; D016993:Chlamydophila pneumoniae; D005260:Female; D006360:Heat-Shock Proteins / Q000097:blood; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007194:India; D007249:Inflammation / Q000097:blood*; D008297:Male; D008875:Middle Aged; D019798:Neopterin / Q000097:blood; D009195:Peroxidase / Q000097:blood; D012307:Risk Factors; D020521:Stroke / Q000097:blood*; D055815:Young Adult; D018834:Chaperonin 60; D024101:Mitochondrial Proteins
chemical_list: D000907:Antibodies, Bacterial; D015415:Biomarkers; D006360:Heat-Shock Proteins; D007136:Immunoglobulins; D019798:Neopterin; D009195:Peroxidase; C060293:HSPD1 protein, human; D018834:Chaperonin 60; D024101:Mitochondrial Proteins
keywords: Acute ischemia; C pneumoniae; inflammatory biomarkers; stroke severity