Optimisation of herpes simplex virus-based vectors for delivery to human peripheral blood mononuclear cells

Hearing restoration in a deaf animal model with intravenous transplantation of mesenchymal stem cells derived from human umbilical cord blood

OBJECTIVE

This study was performed to confirm the effect of transplantation of human umbilical cord blood mesenchymal stem cells (UCB-MSCs) on hearing restoration in a sensorineural hearing loss (SNHL) animal model.

MATERIAL AND METHODS

UCB was collected from pregnant women after obtaining consent, and mesenchymal stem cells (MSCs) were extracted. We established an SNHL model and transplanted UCB-MSCs through the brachial vein of the guinea pigs. The animals were divided into 4 groups: animals with normal hearing, animals with SNHL, animals with SNHL and injected with saline, and animals with SNHL and transplanted with UCB-MSCs. Hearing tests were conducted at 1, 3, and 5 weeks, and the results were compared by grading auditory brainstem response (ABR) recordings and distortion product otoacoustic emissions (DPOAEs) for each treatment. Lastly, cochlear pathological features were examined, and surface preparations and morphological changes in each animal model were compared using hematoxylin and eosin staining and light microscopy studies.

RESULTS

In SNHL group, decreased DPOAEs and increased ABR threshold were noted. Furthermore, in the SNHL group, ABR hearing thresholds were unconverted and were similar to those observed in deafness. The transplanted UCB-MSC group showed a significant improvement in hearing threshold (40 dB) compared to that in all the SNHL group (80-90 dB). Examination of the SNHL animals' cochlear morphological features demonstrated a noticeable lack of spiral ganglion cells and also showed degenerated outer hair cells. However, the transplanted UCB-MSCs showed an increase in spiral ganglion and hair cells.

CONCLUSION

Intravenous transplantation of UCB-MSCs can enhance hearing thresholds, outer-hair cells and increase the number of spiral ganglion neurons (SGNs).

In vivo antitumour activity of PBMCs via genetic modification of single-chain immunotoxin

AIM

To investigate In vivo antitumour activity of single-chain immunotoxin (sFv-TNF-α fusion protein).

METHODS

HCC-specific killer cells were generated by transducing the recombinant retroviral virus in supernatant of the virus producing cells (C₂₂) into human peripheral blood mononuclear cells (PBMCs). SMMC-7721 xenograft nude mice were given iv either 1×10⁶ (0.2 mL) transduced or mock-transduced PBMCs once five days for three weeks and tumour growth was detected.

RESULTS

Tumour growth were (20.8±4.9) mg/d in PBMCs/PST group and (28.5±6.7)mg/d in PBMCs/ pLXSN group, with a significant difference (P<0.05).

CONCLUSION

Genetic modification of PBMCs by single-chain immunotoxin has antitumour activity In vivo.

In vitro cytotoxicity of PBMCs via genetic modification of single-chain immunotoxin

AIM: To investigate the selective cytotoxicity of single-chain immunotoxin (sFv-TNF-α fusion proteins) in cell line SMMC-7721.

METHODS: HCC-specific killer cells were generated by transducing the recombinant retroviral virus in supernatant of the virus producing cells into human peripheral blood mononuclear cells (PBMCs). PCR and RT-PCR were used to detect integration and transcription of the sFv-TNF-α gene in transduced PBMCs (PBMCs/PST). MTT method was used to detect antitumour activity of the sFv-TNF-α fusion proteins.

RESULTS: There was integrated sFv-TNF-α gene in the genome of PBMCs/PST, and PBMCs/PST were able to express the fusion sFv-TNF-α proteins. Cell killing was significant in HCC cells co-cultivated with PBMCs/PST, whereas the PBMCs/pLXSN control cells had no significant cytotoxic effects on HCC cells.

CONCLUSION: Expression of sFv-TNF-α fusion proteins in PBMCs/PST has cytotoxicity to HCC cells in vitro.