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Purpose: Laotians and Lao Isan are widely spread Lao groups who live in Laos and northeastern Thailand, respectively. We explored the genetic structure between them and other ethnic groups from Thailand to clarify historical patterns of admixture between Tai-Kadai and Austroasiatic speakers, and to expand the forensic reference database for the region., Subjects and Methods: We combined new genetic data for 554 individuals from 12 populations, typed for 15 autosomal short tandem repeats, with available data from 14 populations from Thailand, for a total of 1,153 raw genotypes belonging to 26 populations. We calculated forensic parameters and performed various analyses on genetic diversity, genetic structure, genetic admixture, and genetic relationships among the studied populations., Results: Forensic estimators suggest a good power of discrimination with the combined power of exclusion ranging from 0.993628 to 0.999991 and a combined power of discrimination value greater than 0.99999999. Generally, the two Laotian groups were genetically similar, but the central Laotians from Vientiane have a closer genetic relationship to the Lao Isan than the northern Laotians from Luang Prabang. The Lao genetic ancestry forms the majority of the Lao Isan genetic makeup, while Austroasiatic ancestry is present at ∼10%-50%., Conclusions: Lao Isan populations show signs of Lao ancestry and admixture with local Austroasiatic ancestry, which reflect historical migrations from Laos to Thailand. Lao speakers are genetically more homogeneous than Austroasiatic speakers, suggesting differential historical processes., (© 2020 John Wiley & Sons Ltd/University College London.)

Background: Porcine Reproductive and Respiratory Syndrome virus (PRRSV) induces several immunomodulatory mechanisms that resulted in delayed and ineffective anti-viral immune responses. Recently, it has been shown that intradermal immunization of plasmid encoding truncated nucleocapsid protein (pORF7t) could reduce PRRSV-induced immunomodulatory activities and enhances anti-PRRSV immunity in vaccinated pigs. However, intradermal immunization may not be practical for farm setting. Currently, there are several transdermal delivery systems available in the market, although they were not originally designed for plasmid delivery., Objectives: To investigate the potential use of a transdermal delivery system for delivering of pORF7t and its immunological outcomes., Method: The immunomodulatory effects induced by transdermal delivery of pORF7t were compared with intradermal immunization in an experimental pig model. In addition, immunomodulatory effects of the DNA vaccine were determined in the fattening pigs kept in a PRRSV-positive farm environment, and in the experimental pigs receiving heterologous prime-boost, pORF7t-modified live vaccine (MLV) immunization., Result: The patterns of PRRSV-specific cellular responses induced by transdermal and intradermal immunizations of pORF7t were similar. Interestingly, the pigs transdermally immunized with pORF7t exhibited higher number of PRRSV-specific CD8(+)IFN-γ(+) cells. Pigs immunized with pORF7t and kept at PRRSV-positive environment exhibited enhanced PRRSV-specific IFN-γ(+) production, reduced numbers of regulatory T lymphocytes (Tregs) and lower lung scores at the end of the finishing period. In the heterologous prime-boost experiment, priming with pORF7t prior to MLV vaccination resulted in significantly higher numbers of CD3(+)IFN-γ(+) subpopulations, lower numbers of PRRSV-specific CD3(+)IL-10(+) cells and Tregs, and rapid antibody responses in immunized pigs., Conclusion: Transdermal immunization with pORF7t reduced PRRRSV-induced immunomodulatory effects and enhanced long-term PRRSV-specific cellular responses in vaccinated pigs. Furthermore, heterologous DNA-MLV prime-boost immunization significantly improved the quality of PRRSV-specific cellular and humoral immunity. The information could benefit the future development of PRRSV management and control strategies., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Viral-induced interleukin (IL)-10 and regulatory T lymphocytes (Tregs) are believed to play a major role in shaping the immunological and clinical outcomes following Porcine Reproductive and Respiratory Syndrome virus (PRRSV) infection. Recently, it has been shown that PRRSV nucleocapsid (N) protein can induce IL-10 production which is essential for induction of PRRSV-specific Tregs. We hypothesized that immunity to N protein should reduce PRRSV-induced negative immunomodulatory effects which will be essential for establishing proper anti-PRRSV immunity in infected pigs., Objectives: To investigate the immunomodulatory effects of DNA vaccine encoding a linearized, truncated form of PRRSV-N protein (pORF7t) which was designed to preferentially induce cell-mediated immunity against PRRSV N protein., Method: Immunomodulatory effects of the novel DNA vaccine were investigated in an experimental vaccinated-challenged model. In addition, long-term immunomodulatory effects of the DNA vaccine were investigated in vaccinated pigs kept at the PRRSV-positive environment until the end of the fattening period. Pigs were vaccinated either prior to or following natural PRRSV infection., Result: The results indicated that pORF7t could modulate the anti-PRRSV immune responses and promote the control of viral replication in the vaccinated-challenged pigs. Immunized pigs exhibited increased numbers of PRRSV-specific activated CD4(+)CD25(+) lymphocytes, reduced numbers of PRRSV-specific Tregs, and rapid viral clearance following infection. In a long-term study, regardless of the time of vaccination, DNA vaccine could modulate the host immune responses, resulted in enhanced PRRSV-specific IFN-γ producing cells, and reduced numbers of PRRSV-specific Tregs, without evidence of enhanced antibody responses. No vaccine adverse reaction was observed throughout the study., Conclusion: This study revealed the novel concept that PRRSV-specific immunity can be modulated by induction of cell-mediated immunity against the nucleocapsid protein. This concept could potentially benefit the development of PRRSV management and control strategies., (Copyright © 2015 Elsevier Ltd. All rights reserved.)