Polymorphisms in major cytokine genes: a study among human immunodeficiency Virus-1 serodiscordant couples in Mumbai, India

PURPOSE

Polymorphism in cytokine genes may affect its production, which play an important role in modulation of human immunodeficiency virus (HIV) infection. Evaluation of these polymorphisms might help to understand why some individuals remain uninfected in spite of several exposures to HIV infection, such as the negative spouses of discordant couples. The aim of this study was to evaluate the association of 22 single nucleotide polymorphisms (SNPs) in 13 cytokine genes and their receptors with HIV infection in serodiscordant couples, attending the Integrated Counselling and Testing Centre of a Municipality Hospital.

MATERIALS AND METHODS

At the end of at least 2 years of follow up, 42 couples were confirmed as being serodiscordant. Genotyping was carried out in blood samples of these couples using the polymerase chain reaction-sequence-specific amplification method.

RESULTS

Significantly high frequency of interleukin-1 receptor antagonist IL-1RA mspa 11100 CC (P=0.04), tumor necrosis factor-alpha TNF-α -238 AG (P=0.01) and IL-4 -33 TT (P=0.01) was observed in HIV seropositives (HSP) while frequency of TNF-α -238 GG (P=0.02) was significantly high among the exposed uninfected (EU). However, application of Bonferroni correction identified only two SNPs i.e., TNF-α -238 AG and IL-4 -33 TT to be significantly associated with the acquisition of HIV. In remaining cytokine genes, no significant association was observed.

CONCLUSION

Our study highlighted possible association of certain specific polymorphisms with HIV transmission, whereas presence or absence of certain other polymorphism in EU individuals might be offering protection from HIV infection. These variations at the genetic level might help to explore new insights into treatment and HIV prevention strategies.

Bacterial vaginosis: a cause of infertility?

Bacterial vaginosis (BV) is a common disorder of the genital tract in women characterized by an alteration of the normal acidic lactobacilli-predominant vaginal ecosystem to a vaginal environment dominated by Gardnerella vaginalis, mycoplasma species and anaerobes, with an increase in pH. The present study evaluated whether BV is associated with reproductive complications in women. BV was screened with a Gram stain of vaginal smear and interpretation was done using the Nugent score. Wet mount and polymerase chain reaction were used to screen other infections. Among 510 enrolled women, 72 (14.1%) had BV. Statistical analysis between the BV negative and positive population revealed a significant association (P = 0.0001) with infertility. In pregnant women, the infection rate was low (P = 0.01). Multiple infections such as Candida, Chlamydia and human papilloma virus were observed in 4.2%, 15.3% and 8.3% of BV-infected women, respectively. Results suggest that BV infection is associated with infertility and its absence leads to pregnancy, emphasizing its screening and treatment.

Use of vaginal pH in diagnosis of infections and its association with reproductive manifestations

Increase in vaginal secretion pH is an indicator of bacterial vaginosis (BV), but is yet to be in use as a diagnostic tool by clinicians. Similarly, no reports are available on the effect of cervical chlamydia infection and different reproductive manifestations on vaginal secretion pH. This study evaluated the use of vaginal pH for screening of BV, the effect of Chlamydia trachomatis (C. trachomatis) infection, and different reproductive manifestations on vaginal pH of women attending the gynecology outpatient department of a general hospital. Vaginal pH was recorded while diagnosing infections in 358 women, among which 45 were with repeated spontaneous abortion, 79 with infertility, 185 had sign and symptoms of lower genital tract infection, and 49 had no history or symptom of any complications or infections. Normal vaginal pH, BV, and C. trachomatis infection were observed in 72.6, 21.5, and 10.1% of women, respectively. BV and C. trachomatis were observed in 78.6 and 4.1% of women, respectively, with high vaginal pH; 12.3% of women with normal vaginal pH had C. trachomatis infection. C. trachomatis infection or different reproductive manifestations do not lead to change in vaginal pH but high vaginal pH correlated with BV and should be used as a simple tool for its diagnosis.