title: Age, environment, and lymphocyte immunization influence the spontaneous resorption rate in the CBA/J x DBA/2J mouse model.
abstract: OBJECTIVE
  This study was designed to examine the influence of age, environment, and lymphocyte immunotherapy on fetal resorption rates in the CBA/J x DBA/2J mouse model.
  
  
  METHODS
  After weaning, CBA/J female mice were randomly allocated to two different environments: room A was a conventional housing facility, and room B was a specific pathogen-free room. They were further divided into two groups in each room according to age (> three months and < or = three months), and mated with CBA/J, DBA/2J, or BALB/c males. The fetal resorption rates were observed. The immunization study was conducted using CBA/J females greater than three months old in room B. Preimmunization with various preparations and dosages of lymphocytes was performed 1 wk before mating with DBA/2J males, and fetal resorption rates were measured to investigate the effect of immunotherapy.
  
  
  RESULTS
  In room A, the fetal resorption rates (9.4 to 11.8%) were not significantly different among the various mating combinations using CBA/J females greater or less than three months of age. In room B, CBA/J females older than three months and mated with DBA/2J males had a higher rate of fetal resorption than those younger than three months (28.9 versus 14.2%) and had higher rate of fetal resorption than those housed and mated in room A (28.9 versus 10.9%). This fetal resorption rate was also higher than those seen with other mating combinations. Preimmunization with male BALB/c splenic lymphocytes (optimal dose 1 x 10(7) cells) was effective in decreasing fetal resorption rate (7.9%), whereas administration of normal saline, or immunization with male CBA/J or DBA/2J lymphocytes was not (20.7 to 27.0%).
  
  
  CONCLUSIONS
  Age and environment influence the spontaneous resorption rate in the CBA/J x DBA/2J mouse model. The high fetal resorption rate of older CBA/J females mated with DBA/2J males in a pathogen-free environment can be reduced by immunization with BALB/c splenic lymphocytes. These results suggested that a variety of mechanisms might initiate early pregnancy failure and that immunological modulation during implantation might be a nonspecific factor.
authors.affiliation: Department of Obstetrics and Gynecology, College of Medicine, National Taiwan University, Taipei, Republic of China.
authors.forename: H N
authors.initials: HN
authors.lastname: Ho
authors.forename: S U
authors.initials: SU
authors.lastname: Chen
authors.forename: Y S
authors.initials: YS
authors.lastname: Yang
authors.forename: S C
authors.initials: SC
authors.lastname: Huang
authors.forename: T Y
authors.initials: TY
authors.lastname: Lee
authors.forename: T J
authors.initials: TJ
authors.lastname: Gill
mesh_terms: D000022:Abortion, Spontaneous / Q000276:immunology*; D000375:Aging / Q000276:immunology; D000818:Animals; D004195:Disease Models, Animal; D004780:Environment, Controlled; D005260:Female; D005327:Fetal Resorption / Q000276:immunology*; D007114:Immunization; D008214:Lymphocytes / Q000276:immunology; D008285:Major Histocompatibility Complex / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D011247:Pregnancy