title: Xenotransplantation of uterine leiomyoma in Wistar rats: a pilot study.
abstract: OBJECTIVE
  To evaluate whether xenografts derived from hysterectomized patients would implant successfully and lead to uterine leiomyoma in Wistar rats.
  
  
  METHODS
  This experimental study examined six female Wistar rats implanted with uterine leiomyoma obtained from patients who underwent hysterectomies at the gynecological surgery service of the HUUFMA. The rats were divided into two groups. Group I consisted of three rats in which the uterine leiomyoma had been implanted in the parietal peritoneum, and group II consisted of three rats in which the uterine leiomyoma was implanted in the subcutaneous tissue. The immunosuppressant mycophenolate mofetil (MMF) was administered orally by gavage (at a dose of 40 mg/kg of body weight) to prevent transplant rejection starting 15 days before the transplant and continuing throughout the entire experiment. After four weeks, necrosis and neovascularization were evaluated histologically in both groups and were classified as either absent or present. Lymphocytic inflammatory infiltration was also examined and classified as mild, moderate or intense (by hematoxylin and eosin staining), and fibrosis was classified as grade I-III (by Masson's trichrome staining).
  
  
  RESULTS
  Necrosis was absent from all three rats in group I and was observed in only one rat from group II. Neovascularization was present in two rats from group I and in only one rat from group II. The lymphocytic inflammatory infiltrate was mild in two rats and moderate in one rat from group I, and it was moderate in two rats and intense in one rat from group II. Two rats from group 1 exhibited grade III fibrosis, and one rat presented grade I fibrosis. In group II, two rats presented grade I fibrosis and one rat had grade II fibrosis. When necrosis and neovascularization were evaluated as variables, group I demonstrated greater evidence of successful implantation when compared to group II, indicating that the peritoneal implantation technique produces better results than the subcutaneous approach (p=0.039).
  
  
  CONCLUSIONS
  This study demonstrates that the xenotransplantation of uterine leiomyoma into the parietal peritoneum is more effective than the xenotransplantation of uterine leiomyoma into the subcutaneous tissue, and it describes a promising new model for the study of leiomyoma in vivo.
authors.affiliation: Experimental Surgery Laboratory of the Federal University of Maranhão (Laboratório de Cirurgia Experimental da Universidade Federal do Maranhão - LabCEMA), São Luis, MA, Brazil.
authors.forename: Willane Bandeira de
authors.initials: WB
authors.lastname: Sousa
authors.affiliation: Pain Medicine Service at the Maranhão State University Teaching Hospital (Hospital Universitário da Universidade Federal do Maranhão - HUUFMA), São Luis, MA, Brazil.
authors.forename: João Batista Santos
authors.initials: JB
authors.lastname: Garcia
authors.affiliation: Experimental Surgery Laboratory of the Federal University of Maranhão (Laboratório de Cirurgia Experimental da Universidade Federal do Maranhão - LabCEMA), São Luis, MA, Brazil. Electronic address: j.nogueira.n@uol.com.br.
authors.forename: João
authors.initials: J
authors.lastname: Nogueira Neto
authors.affiliation: Experimental Surgery Laboratory of the Federal University of Maranhão (Laboratório de Cirurgia Experimental da Universidade Federal do Maranhão - LabCEMA), São Luis, MA, Brazil.
authors.forename: Pablo Gustavo Ribeiro
authors.initials: PG
authors.lastname: Furtado
authors.affiliation: Experimental Surgery Laboratory of the Federal University of Maranhão (Laboratório de Cirurgia Experimental da Universidade Federal do Maranhão - LabCEMA), São Luis, MA, Brazil.
authors.forename: Jonhnathan Adriano Araújo dos
authors.initials: JA
authors.lastname: Anjos
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005355:Fibrosis; D006084:Graft Rejection / Q000517:prevention & control; D006801:Humans; D007166:Immunosuppressive Agents; D007889:Leiomyoma / Q000473:pathology*; D009173:Mycophenolic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives; D009336:Necrosis / Q000473:pathology; D009368:Neoplasm Transplantation / Q000379:methods*; D009389:Neovascularization, Pathologic / Q000473:pathology; D010537:Peritoneum / Q000473:pathology*; D010865:Pilot Projects; D051381:Rats; D017208:Rats, Wistar; D040521:Subcutaneous Tissue / Q000473:pathology*; D014183:Transplantation, Heterologous; D014594:Uterine Neoplasms / Q000473:pathology*
chemical_list: D007166:Immunosuppressive Agents; D009173:Mycophenolic Acid
keywords: Experimental; Uterine leiomyoma; Uterine leiomyoma model; Wistar rats; Xenotransplantation