Molecular detection of adeno-associated virus in cases of spontaneous and intentional human abortion.
Pregnancy failure is a common event and often of unknown cause. Some viruses are thought to cause abortions including the adeno-associated viruses (AAV), viruses which are regarded as being without any definitive association to any human disease. This study investigated AAV infection in 81 human abortions, both spontaneous and intentional that occurred up to the 23rd week of gestation. Nucleic acid of AAV-2, 3, and 5 types from 118 decidual and chorionic tissues, collected from the patients in this study, was amplified by nested-PCR. In situ hybridization (ISH) was developed with a digoxigenin-labeled AAV probe in paraffin embedded tissues from the AAV positive cases. AAV was observed in 28.4% (23/81) of the cases, of which, 78.3% (18/23) were in the decidua and 21.7% (5/23) in the extravillous trophoblast, the chorionic plate, or chorionic villi fragments. AAV-2, the only type detected, occurred in 32.3% (22/68) and in 7.7% (1/13) of the spontaneous and intentional abortions, respectively. ISH revealed AAV in the decidua, chorionic tissue or chorionic plate and extravillous trophoblast. The detection of only AAV-2 type indicates that it is the most frequent in the population studied and/or shows tissue tropism. The presence of AAV in decidual or trophoblastic cells in cases of abortion, as observed by ISH, implies that the virus could jeopardize the pregnancy. The significant predominance in spontaneous cases suggests possibly a causal association between AAV and abortion.
Pereira
Christiane Curi
CC
Center of Infectious Diseases, Health Science Center, Federal University of Espírito Santo, Vitória, ES, Brazil.
de Freitas
Luciana Bueno
LB
de Vargas
Paulo Roberto Merçon
PR
de Azevedo
Maria Luiza Borges
ML
do Nascimento
Jussara Pereira
JP
Spano
Liliana Cruz
LC
D000022:Abortion, Spontaneous / Q000209:etiology* / Q000821:virology; D002823:Chorion / Q000821:virology; D004279:DNA, Viral / Q000235:genetics / Q000302:isolation & purification; D003656:Decidua / Q000821:virology; D000229:Dependovirus / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D017403:In Situ Hybridization / Q000379:methods; D007231:Infant, Newborn; D010322:Parvoviridae Infections / Q000150:complications* / Q000175:diagnosis* / Q000821:virology; D057089:Pathology, Molecular / Q000379:methods; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy; D014327:Trophoblasts / Q000821:virology; D014773:Virology / Q000379:methods
D004279:DNA, Viral