Characterization of an immortalized human cell line derived from neonatal foreskin diploid fibroblasts

Flos Farfarae Inhibits Enterovirus 71-Induced Cell Injury by Preventing Viral Replication and Structural Protein Expression

Enterovirus 71 (EV71) infection can cause airway symptoms, brainstem encephalitis, neurogenic shock, and neurogenic pulmonary edema with high morbidity and mortality. There is no proven therapeutic modality. Flos Farfarae is the dried flower bud of Tussilago farfara L. that has been used to manage airway illnesses for thousands of years. It has neuro-protective activity and has been used to manage neuro-inflammatory diseases. However, it is unknown whether Flos Farfarae has activity against EV71-induced neuropathy. The current study used both human foreskin fibroblast (CCFS-1/KMC) and human rhabdomyosarcoma (RD) cell lines to test the hypothesis that a hot water extract of Flos Farfarae could effectively inhibit EV71 infection. The authenticity of Flos Farfarae was confirmed by HPLC-UV fingerprint. Through plaque reduction assays and flow cytometry, Flos Farfarae was found to inhibit EV71 infection ([Formula: see text]). Inhibition of viral replication and protein expression were further confirmed by reverse transcription polymerase chain reaction (RT-PCR) and quantitative RT-PCR (qRT-PCR), and western blot, respectively. The estimated IC[Formula: see text]s were 106.3[Formula: see text][Formula: see text]g/mL in CCFS-1/KMC, and 15.0[Formula: see text][Formula: see text]g/mL in RD cells. Therefore, Flos Farfarae could be beneficial to inhibit EV71 infection by preventing viral replication and structural protein expression.

Gan-Lu-Siao-Du-yin, a prescription of traditional Chinese medicine, inhibited enterovirus 71 replication, translation, and virus-induced cell apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Gan-Lu-Siao-Du-yin (GLSDY) is a prescription of traditional Chinese medicine. GLSDY contains 11 ingredients and is commonly used for endemic diseases. Enterovirus 71 (EV71) is an endemic disease that can cause meningoencephalitis with mortality and neurologic sequelae without any effective management. It is unknown whether GLSDY is effective against EV71 infection.

AIM OF THE STUDY

To test the hypothesis that GLSDY can protect cell from EV71-induced injury.

MATERIALS AND METHODS

Effects of a hot water extract of GLSDY on EV71 were tested in human foreskin fibroblast cells (CCFS-1/KMC) and human rhabdomyosarcoma cells (RD cells) by plaque reduction assay and flow cytometry respectively. Inhibition of viral replication was further examined by reverse quantitative RT-PCR (qRT-PCR). Its effect on viral protein translation and virus-induced apoptosis were examined by western blot.

RESULTS

GLSDY was dose-dependently effective against EV71 infection (p<0.0001) in both CCFS-1/KMC cells and RD cells. GLSDY was highly effective when supplemented after viral inoculation (P<0.0001) with an IC50 of 8.7μg/mL. GLSDY inhibited viral RNA replication (P<0.0001), formation of viral structural proteins (VP0, VP1, VP2 and VP3) and non-structural proteins (protease 2B and 3AB). Furthermore, 300μg/mL GLSDY is effective to inhibit virus-induced apoptosis possibly through direct inhibition of caspase-8 and indirectly by inhibition of Bax.

CONCLUSIONS

GLSDY is cheap and readily available to manage EV71 infection by inhibiting viral replication, viral protein formations, and EV71-induced apoptosis.

Yakammaoto inhibits enterovirus 71 infection by reducing viral attachment, internalization, replication, and translation

Enterovirus 71 (EV71) can cause central nervous system infections with mortality and neurologic sequelae. At present, there is no effective therapeutic modality for EV71 infection. The infection is more common in families with poor socioeconomic status. Therefore, finding a readily available, cost-effective therapeutic modality would be very helpful to these socioeconomically disadvantaged families. Yakammaoto is a cheap and readily available traditional prescription that is proven to have antiviral activity against coxsackievirus B4 (CVB4). CVB4 and EV71 are enteroviruses. In this study, we evaluated the antiviral activity of hot water extract of yakammaoto against EV71. The results of plaque reduction assay and flow cytometry demonstrated that yakammaoto dose dependently inhibited EV71 infection. In addition, reverse transcription-polymerase chain reaction (RT-PCR) and quantitative RT-PCR results showed that yakammaoto reduced viral replication. Western blotting analysis showed that yakammaoto can inhibit viral protein production. Thus, our results suggest that yakammaoto should be considered to manage EV71 infection in the future.

Water extract of Glycyrrhiza uralensis inhibited enterovirus 71 in a human foreskin fibroblast cell line

Human infection by enterovirus type 71 (EV71) can cause life-threatening meningo-encephalitis. Currently, there is no effective anti-EV71 therapy available. Since EV71 infection commonly involves skin lesions, we tested our hypothesis that water extract of Glycyrrhiza uralensis (G. uralensis) could inhibit the cytopathic effects of EV71 in a human foreskin cell line by using an XTT-based method. Our results showed that the water extract of G. uralensis at 3,000 microg/ml has only 30% cytotoxicity on host cells, and furthermore, that the water extract of G. uralensis at 0.1 microg/ml could effectively protect host cells against EV71 infection (p < 0.0001). The half maximal inhibitory concentration (IC(50)) was 0.056 microg/ml with a selective index greater than 50,000. The water extract of G. uralensis exerted its effects not only by preventing viral attachment (p < 0.0001), but also by inhibiting the penetration of the virus (p < 0.0001). EV71 infection caused cells to produce significant amounts of IFN-beta (p = 0.0003). However, the anti-EV71 activity of the water extract of G. uralensis was not mediated by IFN. In conclusion, the water extract of G. uralensis possesses potent anti-EV71 effects with less cytotoxicity. Its low IC(50) and high 50% cytotoxic concentration (CC(50)) values suggest that it is a promising anti-EV71 agent.

Sheng-Ma-Ge-Gen-Tang inhibited Enterovirus 71 infection in human foreskin fibroblast cell line

ETHNOPHARMACOLOGICAL RELEVANCE

Sheng-Ma-Ge-Gen-Tang (SMGGT), a popular prescription of Chinese traditional medicine, has been used to manage measles infection of children for thousands of years. There are evidences to presume a wider spectrum of antiviral activity of SMGGT. However, SMGGT has not been proven to have activity against EV71 infection.

AIM OF THE STUDY

We tested the hypothesis that SMGGT could inhibit cytotoxic effect of EV71.

MATERIALS AND METHODS

Human foreskin fibroblast cell line was used for viral culture. Cytotoxicity was examined by XTT assay.

RESULTS

SMGGT could inhibit cytopathy induced by EV71 when given before (p<0.0001), in association with (p<0.0001), or after viral infection (p<0.0001). SMGGT was effective (IC(50): 0.21 microg/ml) and safe (SI: more than 24,000). SMGGT could inhibit viral attachment (p<0.0001) and penetration (p<0.0001). EV71 infection could induce cellular interferon production (p<0.0001). However, SMGGT affected neither the virus-induced (p=0.9913), nor the constitutional interferon production (p>0.05). Therefore, SMGGT had direct anti-viral activity not mediated by interferon.

CONCLUSIONS

SMGGT was effective on management of the disease induced by EV71 infection.

Molecular cytogenetic characterization of human papillomavirus16-transformed foreskin keratinocyte cell line 16-MT

Anogenital cancers are closely associated with human papillomavirus (HPV), and HPV-infected individuals, particularly those with high-grade dysplasias, are at increased risk for cervical and anal cancers. Although genomic instability has been documented in HPV-infected keratinocytes, the full spectrum of genetic changes in HPV-associated lesions has not been fully defined. To address this, we examined an HPV16-transformed foreskin keratinocyte cell line, 16-MT, by GTG-banding, spectral karyotyping (SKY), and array comparative genomic hybridization (array CGH); these analyses revealed multiple numerical, complex, and cryptic chromosome rearrangements. Based on GTG-banding, the 16-MT karyotype was interpreted as 78-83,XXY,+add(1)(p36.3),+3,+4,+5,+5,+7,+8,+i(8)(q10)x2,+10,?der(12),der(13;14)(q10;q10),+15,+16,add(19)(q13.3),+21,+21,-22[cp20]. Multicolor analysis by SKY confirmed and further characterized the anomalies identified by GTG banding. The add(1) was identified as a der(1)(1qter-->1q25::1p36.1-->1qter), the add(19) as a dup(19), and the der(12) interpreted as a der(11) involving a duplication of chromosome 11 material and rearrangement with chromosome 19. In addition, previously unidentified der(9)t(9;22), der(3)t(3;19), and der(4)t(4;9) were noted. The 16-MT cell line showed losses and gains of DNA due to unbalanced translocations and complex rearrangements of regions containing known tumor suppressor genes. Chromosomal changes in these regions might explain the increased risk of cancer associated with HPV. Also, array CGH detected copy-number gains or amplifications of chromosomes 2, 8, 10, and 11 and deletions of chromosomes 3, 4, 11, and 15. These results provide the basis for the identification of candidate oncogenes responsible for cervical and anal cancer in amplified regions, and for putative tumor suppressor genes in commonly deleted regions like 11q22-23. Furthermore, these data represent the first full characterization of the HPV-positive cell line 16-MT.