Immortalized Human Oviductal Cells (OE-E6/E7)

Human Sperm DNA Damage has an Effect on Immunological Interaction Between Spermatozoa and Fallopian Tube

Toll-like receptors are crucial for the immune interaction of spermatozoa with the fallopian tube, influencing ovulation, sperm capacitation, fertilization, and pregnancy. Zandieh et al. examined how sperm with high DNA fragmentation (high DF) affects the expression of toll-like receptors, adaptor molecules, and cytokines in the human fallopian tube cell line (OE-E6/E7), compared to normal sperm.

Semen samples were collected from 10 infertile males with high DF (>20%) and 10 healthy donors with DF 1-3%. After preparation, samples were co-cultured with OE-E6/E7 cells. TUNEL results divided samples into high (20-25%) and low DF groups (1-3%). Figure 1 presents images of positive (A) and negative (B) controls and a sample with fragmented DNA spermatozoa (C). Only complete spermatozoa were considered; heads without tails were excluded. Prior research revealed that OE-E6/E7 expresses TLR1-6 at mRNA and protein levels. Figure 2 displays TLR1-6 gene expression profiles in OE-E6/E7 cells with high and low DF groups. TLR1-6 genes showed significantly higher expression with high DF sperm. Adaptor molecule expression was also significantly higher in the high DF group, except in the TRAM pathway (Fig. 3).

Fig. 1. Terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay (Zandieh Z, Ashrafi M, et al., 2019).

Fig. 2. The mean relative expression of TLR genes 1-6 in OE-E6/E7 cells co-cultured with high and low DF groups (Zandieh Z, Ashrafi M, et al., 2019).

Fig. 3. The mean relative expression of adaptor molecules MyD88, TIRAP, TRIF (TICAM 1), TRAM (TICAM 2) in high DNA fragmentation (DF) and low DF groups (Zandieh Z, Ashrafi M, et al., 2019).

Effect of LNG on Fallopian Tube Epithelium Receptivity

Previous study of Li's team indicated that emergency contraception, including levonorgestrel and progesterone, could lead to ectopic pregnancy following contraception failure. However, their understanding of the effects of levonorgestrel and progesterone on oviductal physiology is limited.

To determine whether LNG affects the receptivity of the fallopian tubal epithelium, they subjected the tubal epithelial cell line OE-E6/E7 to different doses of LNG and P4 and detected the expression of various receptive markers, including LIF, STAT3, IGFBP1, ITGB3, MUC1, and ACVR1B, through qRT-PCR and western blot analyses. However, the expression of these receptive markers did not show any significant changes following the administration of LNG or P4, regardless of the dose (Fig. 4). Furthermore, they performed JAr spheroid-fallopian tubal epithelial cell attachment assays. Spheroids of approximately 60–150 μm were produced from JAr cells and allowed to attach to a monolayer of OE-E6/E7 cells (Fig. 5a) that had been previously treated with different doses of LNG and P4, and the percentages of attached JAr spheroids did not show any significant differences among the groups (Fig. 5c-d).

Fig. 4. Effects of different concentrations of LNG and P4 on the expression of receptivity markers in the fallopian tubes (Li C, Zhang HY, et al., 2018).

Fig. 5. Effects of different concentrations of LNG and P4 on JAr spheroid- fallopian tubal attachment rates (Li C, Zhang HY, et al., 2018).