title: Humoral immune responses to periodontal pathogens in the elderly.
abstract: OBJECTIVE
  Elderly people are thought to be more susceptible to periodontal disease due to reduced immune function associated with aging. However, little information is available on the nature of immune responses against putative periodontal pathogens in geriatric patients. The purpose of this study was to evaluate the serum IgG antibody responses to six periodontal pathogens in geriatric subjects.
  
  
  METHODS
  The study population consisted of 85 geriatric patients and was divided into three groups: 29 mild (MCP), 27 moderate (MoCP) and 29 severe (SCP) chronic periodontitis patients. Serum levels of IgG antibody to Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Prevotella intermedia were measured by enzyme-linked immunosorbent assay (ELISA) and compared among the groups.
  
  
  RESULTS
  All three groups showed levels of serum IgG in response to P. gingivalis, A. actinomycetemcomitans, and P. intermedia that were three to four times higher than levels of IgG to T. forsythia, T. denticola, and F. nucleatum. There were no significant differences among all three groups in IgG response to P. gingivalis (P=0.065), T. forsythia (P=0.057), T. denticola (P=0.1), and P. intermedia (P=0.167), although the IgG levels tended to be higher in patients with SCP than in those with MCP or MoCP (with the exception of those for P. intermedia). In contrast, there were significant differences among the groups in IgG levels in response to F. nucleatum (P=0.001) and A. actinomycetemcomitans (P=0.003). IgG levels to A. actinomycetemcomitans were higher in patients with MCP than in those with MoCP or SCP.
  
  
  CONCLUSIONS
  When IgG levels were compared among three periodontal disease groups, only IgG levels to F. nucleatum significantly increased with the severity of disease. On the contrary, IgG levels to A. actinomycetemcomitans decreased significantly in patients with SCP compared to those with MCP. There were no significant differences in the IgG levels for P. gingivalis, T. forsythia, T. denticola, and P. intermedia among geriatric patients with chronic periodontitis.
authors.affiliation: Department of Oral & Maxillofacial Surgery, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Uttom
authors.initials: U
authors.lastname: Shet
authors.affiliation: Department of Oral & Maxillofacial Surgery, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Hee-Kyun
authors.initials: HK
authors.lastname: Oh
authors.affiliation: Department of Periodontology, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Chung
authors.affiliation: Department of Periodontology, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Young-Joon
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Periodontology, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Ok-Su
authors.initials: OS
authors.lastname: Kim
authors.affiliation: Department of Orthodontics, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Hoi-Jeong
authors.initials: HJ
authors.lastname: Lim
authors.affiliation: Department of Preventive Medicine, Chonnam National University Medical School, Gwangju, Korea.
authors.forename: Min-Ho
authors.initials: MH
authors.lastname: Shin
authors.affiliation: Department of Periodontology, Chonnam National University School of Dentistry, Gwangju, Korea. ; Department of Dental Education, Dental Science Research Institute, Chonnam National University School of Dentistry, Gwangju, Korea.
authors.forename: Seok-Woo
authors.initials: SW
authors.lastname: Lee
keywords: Chronic periodontitis; Disease progression; Enzyme-Linked Immunosorbent Assay; Geriatrics; Immunoglobulin G