Mycobacterium bovis Bacille Calmette-Guérin as a Vaccine Vector for Global Infectious Disease Control

Mycobacterium bovis bacille Calmette-Guérin (BCG) is the only available vaccine for tuberculosis (TB). Although this vaccine is effective in controlling infantile TB, BCG-induced protective effects against pulmonary diseases in adults have not been clearly demonstrated. Recombinant BCG (rBCG) technology has been extensively applied to obtain more potent immunogenicity of this vaccine, and several candidate TB vaccines have currently reached human clinical trials. On the other hand, recent progress in the improvement of the BCG vector, such as the codon optimization strategy and combination with viral vector boost, allows us to utilize this bacterium in HIV vaccine development. In this paper, we review recent progress in rBCG-based vaccine studies that may have implications in the development of novel vaccines for controlling global infectious diseases in the near future

In Vivo Safety and Persistence of Endoribonuclease Gene-Transduced CD4+ T Cells in Cynomolgus Macaques for HIV-1 Gene Therapy Model

BACKGROUND: MazF is an endoribonuclease encoded by Escherichia coli that specifically cleaves the ACA sequence of mRNA. In our previous report, conditional expression of MazF in the HIV-1 LTR rendered CD4+ T lymphocytes resistant to HIV-1 replication. In this study, we examined the in vivo safety and persistence of MazF-transduced cynomolgus macaque CD4+ T cells infused into autologous monkeys. METHODOLOGY/PRINCIPAL FINDINGS: The in vivo persistence of the gene-modified CD4+ T cells in the peripheral blood was monitored for more than half a year using quantitative real-time PCR and flow cytometry, followed by experimental autopsy in order to examine the safety and distribution pattern of the infused cells in several organs. Although the levels of the MazF-transduced CD4+ T cells gradually decreased in the peripheral blood, they were clearly detected throughout the experimental period. Moreover, the infused cells were detected in the distal lymphoid tissues, such as several lymph nodes and the spleen. Histopathological analyses of tissues revealed that there were no lesions related to the infused gene modified cells. Antibodies against MazF were not detected. These data suggest the safety and the low immunogenicity of MazF-transduced CD4+ T cells. Finally, gene modified cells harvested from the monkey more than half a year post-infusion suppressed the replication of SHIV 89.6P. CONCLUSIONS/SIGNIFICANCE: The long-term persistence, safety and continuous HIV replication resistance of the mazF gene-modified CD4+ T cells in the non-human primate model suggests that autologous transplantation of mazF gene-modified cells is an attractive strategy for HIV gene therapy

Geographical, genetic and functional diversity of antiretroviral host factor TRIMCyp in cynomolgus macaque (Macaca fascicularis)

The antiretroviral factor tripartite motif protein 5 (TRIM5) gene-derived isoform (TRIMCyp) has been found in at least three species of Old World monkey: rhesus (Macaca mulatta), pig-tailed (Macaca nemestrina) and cynomolgus (Macaca fascicularis) macaques. Although the frequency of TRIMCyp has been well studied in rhesus and pig-tailed macaques, the frequency and prevalence of TRIMCyp in cynomolgus macaques remain to be definitively elucidated. Here, the geographical and genetic diversity of TRIM5α/TRIMCyp in cynomolgus macaques was studied in comparison with their anti-lentiviral activity. It was found that the frequency of TRIMCyp in a population in the Philippines was significantly higher than those in Indonesian and Malaysian populations. Major and minor haplotypes of cynomolgus macaque TRIMCyp with single nucleotide polymorphisms in the cyclophilin A domain were also found. The functional significance of the polymorphism in TRIMCyp was examined, and it was demonstrated that the major haplotype of TRIMCyp suppressed human immunodeficiency virus type 1 (HIV-1) but not HIV-2, whilst the minor haplotype of TRIMCyp suppressed HIV-2 but not HIV-1. The major haplotype of TRIMCyp did not restrict a monkey-tropic HIV-1 clone, NL-DT5R, which contains a capsid with the simian immunodeficiency virus-derived loop between α-helices 4 and 5 and the entire vif gene. These results indicate that polymorphisms of TRIMCyp affect its anti-lentiviral activity. Overall, the results of this study will help our understanding of the genetic background of cynomolgus macaque TRIMCyp, as well as the host factors composing species barriers of primate lentiviruses

Intratracheal trimerized nanobody cocktail administration suppresses weight loss and prolongs survival of SARS-CoV-2 infected mice

新型コロナウイルスを中和するアルパカ抗体 --マウス実験で有効性を確認--. 京都大学プレスリリース. 2023-02-17.BACKGROUND: SARS-CoV-2 Omicron variants are highly resistant to vaccine-induced immunity and human monoclonal antibodies. METHODS: We previously reported that two nanobodies, P17 and P86, potently neutralize SARS-CoV-2 VOCs. In this study, we modified these nanobodies into trimers, called TP17 and TP86 and tested their neutralization activities against Omicron BA.1 and subvariant BA.2 using pseudovirus assays. Next, we used TP17 and TP86 nanobody cocktail to treat ACE2 transgenic mice infected with lethal dose of SARS-CoV-2 strains, original, Delta and Omicron BA.1. RESULTS: Here, we demonstrate that a novel nanobody TP86 potently neutralizes both BA.1 and BA.2 Omicron variants, and that the TP17 and TP86 nanobody cocktail broadly neutralizes in vitro all VOCs as well as original strain. Furthermore, intratracheal administration of this nanobody cocktail suppresses weight loss and prolongs survival of human ACE2 transgenic mice infected with SARS-CoV-2 strains, original, Delta and Omicron BA.1. CONCLUSIONS: Intratracheal trimerized nanobody cocktail administration suppresses weight loss and prolongs survival of SARS-CoV-2 infected mice

Dynamics of cellular immune responses in the acute phase of dengue virus infection.

In this study, we examined the dynamics of cellular immune responses in the acute phase of dengue virus (DENV) infection in a marmoset model. Here, we found that DENV infection in marmosets greatly induced responses of CD4/CD8 central memory T and NKT cells. Interestingly, the strength of the immune response was greater in animals infected with a dengue fever strain than in those infected with a dengue hemorrhagic fever strain of DENV. In contrast, when animals were re-challenged with the same DENV strain used for primary infection, the neutralizing antibody induced appeared to play a critical role in sterilizing inhibition against viral replication, resulting in strong but delayed responses of CD4/CD8 central memory T and NKT cells. The results in this study may help to better understand the dynamics of cellular and humoral immune responses in the control of DENV infection

Long-Term Persistent GBV-B Infection and Development of a Chronic and Progressive Hepatitis C-Like Disease in Marmosets

It has been shown that infection of GB virus B (GBV-B), which is closely related to hepatitis C virus, develops acute self-resolving hepatitis in tamarins. In this study we sought to examine longitudinally the dynamics of viral and immunological status following GBV-B infection of marmosets and tamarins. Surprisingly, two of four marmosets but not tamarins experimentally challenged with GBV-B developed long-term chronic infection with fluctuated viremia, recurrent increase of alanine aminotransferase and plateaued titers of the antiviral antibodies, which was comparable to chronic hepatitis C in humans. Moreover, one of the chronically infected marmosets developed an acute exacerbation of chronic hepatitis as revealed by biochemical, histological, and immunopathological analyses. Of note, periodical analyses of the viral genomes in these marmosets indicated frequent and selective non-synonymous mutations, suggesting efficient evasion of the virus from antiviral immune pressure. These results demonstrated for the first time that GBV-B could induce chronic hepatitis C-like disease in marmosets and that the outcome of the viral infection and disease progression may depend on the differences between species and individuals

Non-human primate model of amyotrophic lateral sclerosis with cytoplasmic mislocalization of TDP-43

Amyotrophic lateral sclerosis is a fatal neurodegenerative disease characterized by progressive motoneuron loss. Redistribution of transactive response deoxyribonucleic acid-binding protein 43 from the nucleus to the cytoplasm and the presence of cystatin C-positive Bunina bodies are considered pathological hallmarks of amyotrophic lateral sclerosis, but their significance has not been fully elucidated. Since all reported rodent transgenic models using wild-type transactive response deoxyribonucleic acid-binding protein 43 failed to recapitulate these features, we expected a species difference and aimed to make a non-human primate model of amyotrophic lateral sclerosis. We overexpressed wild-type human transactive response deoxyribonucleic acid-binding protein 43 in spinal cords of cynomolgus monkeys and rats by injecting adeno-associated virus vector into the cervical cord, and examined the phenotype using behavioural, electrophysiological, neuropathological and biochemical analyses. These monkeys developed progressive motor weakness and muscle atrophy with fasciculation in distal hand muscles first. They also showed regional cytoplasmic transactive response deoxyribonucleic acid-binding protein 43 mislocalization with loss of nuclear transactive response deoxyribonucleic acid-binding protein 43 staining in the lateral nuclear group of spinal cord innervating distal hand muscles and cystatin C-positive cytoplasmic aggregates, reminiscent of the spinal cord pathology of patients with amyotrophic lateral sclerosis. Transactive response deoxyribonucleic acid-binding protein 43 mislocalization was an early or presymptomatic event and was later associated with neuron loss. These findings suggest that the transactive response deoxyribonucleic acid-binding protein 43 mislocalization leads to α-motoneuron degeneration. Furthermore, truncation of transactive response deoxyribonucleic acid-binding protein 43 was not a prerequisite for motoneuronal degeneration, and phosphorylation of transactive response deoxyribonucleic acid-binding protein 43 occurred after degeneration had begun. In contrast, similarly prepared rat models expressed transactive response deoxyribonucleic acid-binding protein 43 only in the nucleus of motoneurons. There is thus a species difference in transactive response deoxyribonucleic acid-binding protein 43 pathology, and our monkey model recapitulates amyotrophic lateral sclerosis pathology to a greater extent than rodent models, providing a valuable tool for studying the pathogenesis of sporadic amyotrophic lateral sclerosis

Age Influences Male's Mating Preferences for Multiparous and Nulliparous Females in the Laboratory-bred Macaca Fascicularis

Most studies of partner choice and preferences in nonhuman primates have been concerned with male social rank. Females select high-ranking males, and high-ranking females can more readily gain access to males. Although researchers have mentioned males’ choices and their preferences for females, papers that focus on male preferences have been few. Past studies suggested that male primates prefer older females. We analyzed data collected by the every-other-day mating system in which a male alternately lived with each of two females. This allowed us to compare the biological and/or physical characteristics of pregnant females with those of nonpregnant females and to minimize social factors. Multiparous and/or older females were more frequently pregnant. In the nulliparous group, females that became pregnant for the first time tended to be younger than the other nonpregnant females paired in the mating set. While males generally prefer parous females, males prefer to mate with younger females among females that have never been pregnant. A female that gets pregnant at a young age could become pregnant again later in life. Such a mating preference would guarantee higher reproductive success for females in the wild as well