A novel polymerase chain reaction (PCR) based assay for authentication of cell lines or tissues from human, pig and chicken origin

A polymerase chain reaction based assay was developed for authentication of cell lines or tissues from human, pig and chicken origin. Specificity was achieved by species specific primer design targeting the mitochondrial D-loop sequence. Amplicon sizes were 114 bp, 169 bp and 645-648 bp for chicken, human and pig derived cell lines, respectively. Primers were tested for species specificity and non-specificity between haplogroups of the same organisms using BLAST tool and subsequently for cross amplification DNA extracted from human, chicken and pig venous blood as a positive control. Primers were also amplifying specific products in DNA extracted from individual cell line in both functional cell models and intentionally mixed cell lines consisting functional cell models. The PCR assay developed in this study represents a low-cost species specific end-point PCR based assay of the mitochondrial D-loop for the authentication of the cell line origin

Increased HIV-1 transcriptional activity and infectious burden in peripheral blood and gut-associated CD4+ T cells expressing CD30

HIV-1-infected cells persist indefinitely despite the use of combination antiretroviral therapy (ART), and novel therapeutic strategies to target and purge residual infected cells in individuals on ART are urgently needed. Here, we demonstrate that CD4+ T cell-associated HIV-1 RNA is often highly enriched in cells expressing CD30, and that cells expressing this marker considerably contribute to the total pool of transcriptionally active CD4+ lymphocytes in individuals on suppressive ART. Using in situ RNA hybridization studies, we show co-localization of CD30 with HIV-1 transcriptional activity in gut-associated lymphoid tissues. We also demonstrate that ex vivo treatment with brentuximab vedotin, an antibody-drug conjugate (ADC) that targets CD30, significantly reduces the total amount of HIV-1 DNA in peripheral blood mononuclear cells obtained from infected, ART-suppressed individuals. Finally, we observed that an HIV-1-infected individual, who received repeated brentuximab vedotin infusions for lymphoma, had no detectable virus in peripheral blood mononuclear cells. Overall, CD30 may be a marker of residual, transcriptionally active HIV-1 infected cells in the setting of suppressive ART. Given that CD30 is only expressed on a small number of total mononuclear cells, it is a potential therapeutic target of persistent HIV-1 infection

Application of Gut Cell Models for Toxicological and Bioactivity Studies of Functional and Novel Foods

The concept of functional and novel foods undoubtedly bears great potential as an asset to human health. However, this very same quest for ever new bioactive ingredients calls for reliable and distinct risk assessment as they may be potentially hazardous to human health. Most of today\u27s methodologies still rely on decades old routines of animal trials and use of tumor-derived cell lines. Since such methodologies are not in line with the actual processes in the human body and with the 3R (replacement, reduction, refinement) concept, the results are often unreliable and misleading. Therefore, in this paper we propose the utilization of available untransformed small intestinal cell lines derived from human and pig tissue of non-tumor origin and describe several available cell models of the gut that offer a functional, close resemblance with the in vivo environment

Biology-inspired microphysiological systems to advance patient benefit and animal welfare in drug development

The first microfluidic microphysiological systems (MPS) entered the academic scene more than 15 years ago and were considered an enabling technology to human (patho)biology in vitro and, therefore, provide alternative approaches to laboratory animals in pharmaceutical drug development and academic research. Nowadays, the field generates more than a thousand scientific publications per year. Despite the MPS hype in academia and by platform providers, which says this technology is about to reshape the entire in vitro culture landscape in basic and applied research, MPS approaches have neither been widely adopted by the pharmaceutical industry yet nor reached regulated drug authorization processes at all. Here, 46 leading experts from all stakeholders - academia, MPS supplier industry, pharmaceutical and consumer products industries, and leading regulatory agencies - worldwide have analyzed existing challenges and hurdles along the MPS-based assay life cycle in a second workshop of this kind in June 2019. They identified that the level of qualification of MPS-based assays for a given context of use and a communication gap between stakeholders are the major challenges for industrial adoption by end-users. Finally, a regulatory acceptance dilemma exists against that background. This t4 report elaborates on these findings in detail and summarizes solutions how to overcome the roadblocks. It provides recommendations and a roadmap towards regulatory accepted MPS-based models and assays for patients' benefit and further laboratory animal reduction in drug development. Finally, experts highlighted the potential of MPS-based human disease models to feedback into laboratory animal replacement in basic life science research

Differentiating Immune Cell Targets in Gut-Associated Lymphoid Tissue for HIV Cure.

The single greatest challenge to an HIV cure is the persistence of latently infected cells containing inducible, replication-competent proviral genomes, which constitute only a small fraction of total or infected cells in the body. Although resting CD4+ T cells in the blood are a well-known source of viral rebound, more than 90% of the body's lymphocytes reside elsewhere. Many are in gut tissue, where HIV DNA levels per million CD4+ T cells are considerably higher than in the blood. Despite the significant contribution of gut tissue to viral replication and persistence, little is known about the cell types that support persistence of HIV in the gut; importantly, T cells in the gut have phenotypic, functional, and survival properties that are distinct from T cells in other tissues. The mechanisms by which latency is established and maintained will likely depend on the location and cytokine milieu surrounding the latently infected cells in each compartment. Therefore, successful HIV cure strategies require identification and characterization of the exact cell types that support viral persistence, particularly in the gut. In this review, we describe the seeding of the latent HIV reservoir in the gut mucosa; highlight the evidence for compartmentalization and depletion of T cells; summarize the immunologic consequences of HIV infection within the gut milieu; propose how the damaged gut environment may promote the latent HIV reservoir; and explore several immune cell targets in the gut and their place on the path toward HIV cure

B cells are the predominant mediators of early systemic viral dissemination during rectal LCMV infection.

Determining the magnitude of local immune response during mucosal exposure to viral pathogens is critical to understanding the mechanism of viral pathogenesis. We previously showed that vaginal inoculation of lymphocytic choriomeningitis virus (LCMV) fails to induce a robust innate immune response in the lower female reproductive tract (FRT), allowing high titer viral replication and a delay in T-cell-mediated viral control. Despite this immunological delay, LCMV replication remained confined mainly to the FRT and the draining iliac lymph node. Here, we show that rectal infection with LCMV triggers type I/III interferon responses, followed by innate immune activation and lymphocyte recruitment to the colon. In contrast to vaginal exposure, innate immunity controls LCMV replication in the colon, but virus rapidly disseminates systemically. Virus-induced inflammation promotes the recruitment of LCMV target cells to the colon followed by splenic viral dissemination by infected B cells, and to a lesser extent by CD8 T cells. These findings demonstrate major immunological differences between vaginal and rectal exposure to the same viral pathogen, highlighting unique risks associated with each of these common routes of sexual viral transmission

B cells are the predominant mediators of early systemic viral dissemination during rectal LCMV infection.

Determining the magnitude of local immune response during mucosal exposure to viral pathogens is critical to understanding the mechanism of viral pathogenesis. We previously showed that vaginal inoculation of lymphocytic choriomeningitis virus (LCMV) fails to induce a robust innate immune response in the lower female reproductive tract (FRT), allowing high titer viral replication and a delay in T-cell-mediated viral control. Despite this immunological delay, LCMV replication remained confined mainly to the FRT and the draining iliac lymph node. Here, we show that rectal infection with LCMV triggers type I/III interferon responses, followed by innate immune activation and lymphocyte recruitment to the colon. In contrast to vaginal exposure, innate immunity controls LCMV replication in the colon, but virus rapidly disseminates systemically. Virus-induced inflammation promotes the recruitment of LCMV target cells to the colon followed by splenic viral dissemination by infected B cells, and to a lesser extent by CD8 T cells. These findings demonstrate major immunological differences between vaginal and rectal exposure to the same viral pathogen, highlighting unique risks associated with each of these common routes of sexual viral transmission

A co-culture model of the developing small intestine offers new insight in the early immunomodulation of enterocytes and macrophages by Lactobacillus spp. through STAT1 and NF-kB p65 translocation.

The early establishment of a complete microbiome has been shown to play an integral part in the development and maintenance of an intact intestine and its immune system, although much remains unknown about the specific mechanisms of immune modulation in newborns. In our study we show in a co-culture model of the undeveloped small intestine that members of Lactobacillus spp. influence STAT1 and NF-kB p65 nuclear translocation in both intestinal epithelial cells as well as underlying macrophages. Moreover, by using imaging flow cytometry we were able to monitor each individual cell and create a framework of the percentage of cells in which translocation occurred in challenged versus control cell populations. We also observed a significant difference in baseline translocation in intestinal cells when cultured alone versus those in a co-culture model, underpinning the importance of 3D models over monolayer set-ups in epithelial in vitro research. In conclusion, our work offers new insights into the potential routes by which the commensal microbiome primes the early immune system to fight pathogens, and shows how strain-specific these mechanisms really are