HspBP1 and anti-HspBP1 levels in the serum of HIV-infected individuals are associated to the disease progression

AIMS

The objective of this research was to quantify the levels of circulating HspBP1 and anti-HspBP1 IgG in HIV-infected individuals and to correlate them with CD4 T cell counts and viral load, as well as to determine the kinetics of those proteins during acute phase.

METHODS AND RESULTS

Sixty serum samples from HIV-positive outpatients, thirty with high viral load and thirty with low viral load were analysed. The HspBP1 and anti-HspBP1 were quantified by ELISA. To investigate the kinetic of HspBP1 and anti-HspBp1 during the acute phase, these proteins and antibodies were quantified in samples of a commercial seroconverting HIV panel. All dosages were compared with the CD4 and CD8 T cell counts and HIV viral load. The results indicated that HIV positive outpatients presented significant increase in HspBP1 and anti-HspBP1 serum levels, compared with uninfected healthy. HspBP1 and anti-HspBP1 were negatively correlated with CD4 counts and CD4:CD8 ratio. In the acute phase, HspBP1 became significantly elevated 15 days after HIV infection.

CONCLUSIONS

These results indicate that the quantification of HspBP1 can be associated to others well-established parameters of the HIV progression.

SIGNIFICANCE AND IMPACT OF THE STUDY

The discovery that HspBp1 and anti-HspBp1 are associated with progression of HIV infection is new and corroborates to validate the quantification of these proteins as an additional strategy in the management of the HIV infection.

High-throughput DNA analysis shows the importance of methylation in the control of immune inflammatory gene transcription in chronic periodontitis

Background

Chronic periodontitis represents a complex disease that is hard to control and is not completely understood. Evidence from past studies suggests that there is a key role for DNA methylation in the pathogenesis of periodontitis. However, all reports have applied technologies that investigate genes in a low throughput. In order to advance in the knowledge of the disease, we analyzed DNA methylation variations associated with gene transcription using a high-throughput assay. Infinium® HumanMethylation450 (Illumina) was performed on gingival samples from 12 periodontitis cases and 11 age-matched healthy individuals. Methylation data of 1,284 immune-related genes and 1,038 cell cycle-related genes from Gene Ontology (GO) and 575 genes from a dataset of stably expressed genes (genes with consistent expression in different physiological states and tissues) were extracted from a microarray dataset and analyzed using bioinformatics tools. DNA methylation variations ranging from −2,000 to +2,000 bp from the transcription start site (TSS) were analyzed, and the results were tested against a differential expression microarray dataset between healthy and periodontitis gingival tissues. Differences were evaluated using tests from the R Statistical Project.

Results

The comparison of probes between periodontitis and normal gingival tissues showed that the mean methylation scores and the frequency of methylated probes were significantly lower in genes related to the immune process. In the immune group, these parameters were negatively correlated with gene expression (Mann-Whitney test, p < 2.2e − 16).

Conclusions

Our results show that variations in DNA methylation between healthy and periodontitis cases are higher in genes related to the immune-inflammatory process. Thus, DNA methylation must be modulating chromatin regions and, consequently, modulating the mRNA transcription of immune-inflammatory genes related with periodontitis, impacting the prognosis of disease.

TLR2 and TLR4 gene promoter methylation status during chronic periodontitis

AIM

The objective of this study was to analyse the status of DNA methylation in the promoter region of the toll-like receptor (TLR)2 and TLR4 genes in gingival tissue samples from healthy subjects, smokers and non-smokers affected by chronic periodontitis.

MATERIAL AND METHODS

Genomic DNA and total RNA were purified from gingival tissue using the TRIZOL reagent protocol. Genomic DNA was then digested by methylation-sensitive restriction enzymes, amplified by polymerase chain reaction (PCR), electrophoresed on a 10% polyacrylamide gel and stained using SYBR Gold. Real-time PCR was also performed to verify the transcript levels.

RESULTS

The CpG dinucleotides analysed were observed to be unmethylated in the majority of DNA samples of the three groups and statistical differences were not found among groups (p>0.05). However, a trend towards methylation was observed in the TLR2 HhaI site in the samples of the periodontitis non-smoker groups. In fact, the analysis of all CpG sites together shows which complete methylation is observed in the shortest level in the samples of periodontitis non-smoker group. The analysis of transcript levels demonstrated no difference among groups (p>0.05).

CONCLUSION

The results demonstrated major unmethylation of the TLR4 gene promoter in all groups. However, the results for the TLR2 gene promoter are inconclusive; this gene was found as a mosaic of methylated and unmethylated DNA in the majority of samples of the three groups and we also observed a trend towards the DNA methylation of CpG sites recognized by the HhaI enzyme.

Recombinant viruses as vaccines against viral diseases

Vaccine approaches to infectious diseases are widely applied and appreciated. Amongst them, vectors based on recombinant viruses have shown great promise and play an important role in the development of new vaccines. Many viruses have been investigated for their ability to express proteins from foreign pathogens and induce specific immunological responses against these antigens in vivo. Generally, gene-based vaccines can stimulate potent humoral and cellular immune responses and viral vectors might be an effective strategy for both the delivery of antigen-encoding genes and the facilitation and enhancement of antigen presentation. In order to be utilized as a vaccine carrier, the ideal viral vector should be safe and enable efficient presentation of required pathogen-specific antigens to the immune system. It should also exhibit low intrinsic immunogenicity to allow for its re-administration in order to boost relevant specific immune responses. Furthermore, the vector system must meet criteria that enable its production on a large-scale basis. Several viral vaccine vectors have thus emerged to date, all of them having relative advantages and limits depending on the proposed application, and thus far none of them have proven to be ideal vaccine carriers. In this review we describe the potential, as well as some of the foreseeable obstacles associated with viral vaccine vectors and their use in preventive medicine.