Evaluation of Apoptotic proteins (p53 and Bcl-2) expression in trophoblastic tissue of women infected with Toxoplasma gondii diagnosed by polymerase chain reaction

Background: Gene amplification methods (PCR, LCR, NASBA, etc.) are now used widely in the diagnosis of infectious diseases. Certain types of oncogene products, are known to be physiologically expressed in the placenta among these products are Bcl-2 and p53 proteins.
Aim: Use of gene amplification (Polymerase Chain Reaction/ PCR) in the investigation and diagnosis of toxoplasmosis .And to evaluate Bcl-2 and p53 as an anti-apoptotic and pro-apoptotic proteins in the trophoblastic tissue of T.gondii positive, negative and induced aborted women.
Materials and methods: A total of forty pregnant women, their age ranged from (20 − 50) years, were enrolled in the current study and were further classified into three categories: Toxoplasma gondii positive patients: with spontaneous miscarriage (20 women), Toxoplasma gondii negative patients: with spontaneous miscarriage (10 women) and control group (women with induced abortion for medical causes) (10 women).
Venous blood was collected from all women, for the detection of specific anti-Toxoplasma gondii IgM in the serum using the ELISA test. polymerase chain reaction technique (PCR) was used for the detection of Toxoplasma gondii DNA in trophoplastic tissue as a diagnostic methods for T.gondii for both positive and negative groups,and for immunohistochemical analysis for the detection of apoptotic proteins (Bcl-2 and p53).
Results: Twelve (40%) samples out of the (30) were negative for anti-Toxoplasma gondii IgM while the rest 18 (60%) were positive for IgM, but when using polymerase chain reaction (PCR) two of the negative samples in ELISA were found to be positive for toxoplasma B1 specific gene. The highest percentage of Bcl-2 was found in the T.gondii negative group (34.90%±3.44) and control group (38.19%±0.79, while the lowest percentage (10.93%±1.44) was found in the T.gondii positive group.
There was no statistical difference (p ≤ 0.363) in the mean percentage of Bcl-2 between T. gondii negative and control group; while there was a high significant differences (p=0.000) in the mean percentage of Bcl-2 in T. gondii positive group compared to cotrols. In addition a high significant differences (p= 0.000) in the mean percentage of Bcl-2 was found between T. gondii positive and negative groups.
The highest percentage of expression of p53 protein was found in the T.gondii positive group (31.56%±1.28) and the lowest percentage was in both T.gondii negative and control groups (18.93±1.054 and 11.73±1.810 respectively).
There was statistical difference (p ≤ 0.003) in the mean percentage of p53 between T.gondii negative and control groups .In addition there was high significant differences (p=0.000) in the mean percentage of p53 between T.gondii positive group and control groups and between T.gondii positive and negative groups.
Conclusiocn:This assures the specificity and sensitivity of polymerase chain reaction as a molecular method for diagnosis of: Toxoplasma gondii. And high levels of p53 protein found in positive samples for toxoplasma gondii infection might indicated the important role of this protein in cell death and induction of apoptosis that lead to the end of pregnancy with abortion. Low levels of Bcl-2 in aborted women infected with T.gondii might indicated that Bcl-2 have no role in preventing or initiate apoptosis.