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At least 19 recordsLinked to original sources
PubMed2025

Variation in Severity of Symptoms Associated With Two Snow Mountain Virus Inocula.

Snow Mountain Virus (SMV), the prototype of genogroup II and genotype II Norovirus (NoV), was used in human challenge studies to examine the infectivity, pathogenicity, and immune response to NoV. Clinical and laboratory data from two previously completed SMV human challenge trials using two different inocula (primary and secondary) were analyzed to compare the infectivity, illness, viral shedding, and serum IgG conversion. The primary and secondary SMV inocula were sequenced for detecting single nucleotide mutations. Of 15 subjects challenged with the primary inoculum between 2000 and 2002, nine were infected, and seven presented with acute gastroenteritis. Of 33 subjects challenged with the secondary inoculum between 2016 and 2018, 25 were infected, and nine presented with acute gastroenteritis. There were no statistically significant differences in overall infection and illness rates between subjects challenged with the primary inoculum versus the secondary inoculum. However, subjects infected with the primary inoculum experienced more severe clinical symptoms of acute gastroenteritis, showing higher severity scores (6.00 vs. 2.94, p = 0.003) compared with those infected with the secondary inoculum. We also observed that infection with the secondary inoculum resulted in longer viral shedding compared with the primary inoculum. Partial sequencing of the SMV genome identified three mutations in both inocula. Understanding the differences between these two SMV inocula is critical for NoV vaccine evaluation and using a less pathogenic inoculum for a vaccine trial will require more participants to meet the target reduction in illness when evaluating the efficacy of candidate vaccines.

Humans↗
PubMed2026

Whole cell inactivated poly-bacterial preparation MV130 effect on nasal mucosal immunity and experimental human pneumococcal carriage: double-blind randomised controlled trial with controlled human infection model.

BACKGROUND: Bacterial mucosal immunotherapy has shown protection of children and adults from both viral and bacterial respiratory infections, offering the potential to reduce antimicrobial use, and hence also control antimicrobial resistance (AMR). Pneumococcal carriage of vaccine type Streptococcus pneumoniae remains high in Malawi despite infant conjugate vaccination and AMR is increasing. We compared nasal inflammation following sublingual bacterial immunotherapy including S. pneumoniae (MV130, Inmunotek, Spain) or placebo and determined the effect in an experimental human pneumococcal carriage model. METHODS: A double-blind, randomised, placebo-controlled trial in healthy adult volunteers was conducted at Queen Elizabeth Central Hospital in Blantyre, Malawi. Participants were randomly allocated to receive MV130 or placebo sublingually once daily for 42 days. Mucosal inflammation (neutrophil to T cell ratio, NTR) was measured in nasal micro-biopsies. Post-treatment, participants were challenged with 160,000 CFU/naris S. pneumoniae 6B (Spn6b). Experimental pneumococcal carriage rates post inoculation were compared between the two arms. All participants completing the study were included in the analysis. Prospective trial registration: PACTR202403820001276. FINDINGS: 107 participants were enrolled and randomised to MV130/placebo between May and December 2024. There were no serious adverse events, complete compliance was good (72%) and all adverse events were mild. 96 participants (53 male, 43 female) completed the study with 52 participants randomised to MV130 and 44 to placebo. There was no difference in mucosal inflammation (neutrophil to T cell ratio) at day 14 of the intervention MV130 NTR median = 0.737 (IQR 0.294, 2.059) and placebo NTR = 0.831 (IQR 0.450, 2.073), p = 0.64. Secondary analyses showed a rise in mucosal neutrophils after MV130 treatment and after experimental pneumococcal inoculation. There was no difference in nasal or serum anti-pneumococcal immunoglobulin or in experimental pneumococcal carriage proportion between MV130 (12/52, 23%) and placebo (10/44, 23%) groups (unadjusted risk ratio 1.02 (CI 0.49-2.12) p = 1.0). INTERPRETATION: MV130 induced non-specific mild neutrophil inflammation of the nasal mucosa but had no protective effect against experimental human pneumococcal carriage. FUNDING: Wellcome Trust.

Humans↗
PubMed2025

Modulation of the tumor microenvironment by the ubiquitin-proteasome system in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is a leading cause of cancer-related mortality worldwide, with the tumor microenvironment (TME) playing a pivotal role in its progression and therapeutic resistance. The ubiquitin-proteasome system (UPS), a central regulator of intracellular protein degradation, is increasingly recognized for its involvement in cancer pathogenesis, though its specific role in modulating the CRC TME remains to be fully elucidated. This review aims to systematically summarize current evidence on how the UPS influences the immunosuppressive network within the CRC TME and to evaluate its potential as a therapeutic target. METHODS: We conducted a comprehensive literature search in PubMed, Web of Science, and Scopus databases for original research articles and reviews published between January 2010 and August 2025, using keywords including "ubiquitin-proteasome system," "colorectal cancer," "tumor microenvironment,""immune escape,"and "targeted therapy." Studies were selected based on their relevance to UPS-mediated regulatory mechanisms in CRC TME remodeling, immune cell function, and treatment response. RESULTS: Our analysis of preclinical and clinical evidence reveals that the UPS critically regulates immune evasion in CRC through multiple mechanisms: (1) USP14 stabilizes indoleamine 2,3-dioxygenase 1 (IDO1), enhancing tryptophan catabolism and kynurenine accumulation, which suppresses T-cell activity; (2) E3 ligases including SPOP, C-Cbl, KLHL22, and FBW7 modulate PD-L1/PD-1 protein stability via ubiquitination, thereby influencing immune checkpoint signaling; and (3) ZFP91 facilitates K63-linked ubiquitination of PP2Ac, impairing mTORC1-mediated glycolysis in T cells and reinforcing regulatory T-cell immunosuppression. Additionally, the UPS intersects with key oncogenic pathways such as Wnt/β-catenin, NF-κB, and p53, further shaping the immunosuppressive landscape of CRC. CONCLUSIONS: Targeting the UPS represents a promising strategy to reverse immunosuppression and overcome therapy resistance in CRC. The primary advantage of this approach lies in its ability to simultaneously disrupt multiple immunosuppressive pathways within the TME, offering a potential solution to the limitations of single-target therapies. Current approaches include proteasome inhibitors, E3 ligase modulators, and deubiquitinating enzyme inhibitors, with combination regimens-such as UPS inhibitors with immune checkpoint blockade-showing synergistic efficacy in preclinical models. Future efforts should focus on enhancing the selectivity of UPS-targeting agents, minimizing off-target effects, and integrating genomic profiling to guide personalized treatment. While current evidence strongly supports the therapeutic potential of UPS targeting, its establishment as a reliable alternative therapy in the clinic will depend on overcoming these challenges and validating efficacy in human trials. This review underscores the UPS as a central regulator of the CRC TME and provides a rational basis for novel therapeutic development.

Humans↗
PubMed2020

Translating CRISPR-Cas Therapeutics: Approaches and Challenges.

CRISPR-Cas clinical trials have begun, offering a first glimpse at how DNA and RNA targeting could enable therapies for many genetic and epigenetic human diseases. The speedy progress of CRISPR-Cas from discovery and adoption to clinical use is built on decades of traditional gene therapy research and belies the multiple challenges that could derail the successful translation of these new modalities. Here, we review how CRISPR-Cas therapeutics are translated from technological systems to therapeutic modalities, paying particular attention to the therapeutic cascade from cargo to delivery vector, manufacturing, administration, pipelines, safety, and therapeutic target profiles. We also explore potential solutions to some of the obstacles facing successful CRISPR-Cas translation. We hope to illuminate how CRISPR-Cas is brought from the academic bench toward use in the clinic.

CRISPR-Cas Systems↗
PubMed2025

Innate immune molecular landscape following controlled human influenza virus infection.

Viral infections can induce prolonged changes in innate immunity. Here, we use blood samples from a human influenza H3N2 challenge study (NCT03883113) to perform comprehensive multi-omics analyses. We detect remodeling of immune programs in circulating innate immune cells that persist after resolution of the infection. We find changes associated with suppressed inflammation, including decreased cytokine and AP-1 gene expression as well as decreased accessibility at AP-1 targets and interleukin-related gene promoter regions. We also find decreased histone deacetylase gene expression, increased MAP kinase gene expression, and increased accessibility at interferon-related gene promoter regions. Genes involved in inflammation and methylation remodeling show modulation of gene-chromatin site regulatory circuit activity. These results reveal a coordinated rewiring of the molecular landscape in innate immune cells induced by mild influenza virus infection.

Humans↗
PubMed1976

Development and chimpanzee testing of a vaccine against human hepatitis B.

Highly purified hepatitis B virus surface antigen (Australia antigen) purified by physical and chemical procedures from infected human plasma was used to prepare hepatitis B vaccine. The purified antigen was treated with formalin and the vaccine was tested exhaustively for safety by ordinary procedures and additionally in marmosets (for live hepatitis B virus). The vaccine was highly potent, inducing antibody in guinea pigs, grivet monkeys, and chimpanzees given three doses of vaccine containing up to 20 mug of hepatitis B antigen per dose. A protective efficacy trial was carried out in chimpanzees that were given three doses of vaccine subcutaneously and then challenged intravenously with 1000 chimpanzee infectious doses of human hepatitis B virus. All of five unvaccinated control animals developed hepatitis B virus antigenemia following challenge and all of six vaccinated animals were protected, including one animal that had failed to develop detectable antibody following vaccination.

Animals↗
PubMed1976

Vaccination against typhoid fever with a live oral vaccine.

A Salmonella typhi gal E mutant, designated Ty 21a, has been developed on the basis of virulence and protection studies with similar Salmonella typhimurium mutants in mice. Gal E mutants are characterized by a block in the enzyme UDP-4-galactose-epimerase. They owe their outstanding immunizing capacity when used in live oral vaccine to the fact that when galactose is supplied exogenously, as occurs in vivo, wild-type cell wall structures are synthesized. On the other hand, avirulence of these mutants is based upon the fact that when galactose is taken up it is partly accumulated as galactose-1-phosphate and UDP-galactose, which induces lysis of the bacteria. Strain S. typhi Ty 21a does not revert to wild type in vivo and in vitro. Its safety for man has been demonstrated in studies involving 137 adults and 370 children. S. typhi Ty 21a also has been shown to protect against challenge with virulent S. typhi in human volunteers.

Administration, Oral↗
PubMed1978

Effect of CP-20,961, an interferon inducer, on upper respiratory tract infections due to rhinovirus type 21 in volunteers.

Topically administered CP-20,961 is known to stimulate nasal interferon. Studies in volunteers given the drug prior to challenge with rhinovirus have yielded both fairly good results and only fair or poor results. This study was undertaken in an attempt to settle the differences between the results of these trials and to evaluate the possible effectiveness of CP-20, 961 when given after virus challenge. Sixty volunteers were randomly divided into four groups. One group received placebo, the second received the drug on the day before and the day of challenge, the third was given the drug for two days beginning 24 hr after challenge, and the fourth received the drug for two days beginning 48 hr after challenge. The average number and severity of symptoms in the group that received CP-20,961 prior to challenge were about half of those in the control group. There was no decrease, however, in the number and severity of symptoms in the groups that received the drug after challenge.

Adolescent↗
PubMed1978

Double-blind confirmation and treatment of milk sensitivity.

A nine-year-old boy had seasonal and perennial allergic nasal and eye symptoms, as well as the allergic-tension-fatigue syndrome. The presence of milk sensitivity was demonstrated by repeated non-blind and double-blind dietary challenge. He responded well to sublingual milk therapy. The efficacy of this technique was confirmed twice by double-blind challenges.

Animals↗
PubMed2014

Engineering adeno-associated viruses for clinical gene therapy.

Clinical gene therapy has been increasingly successful owing both to an enhanced molecular understanding of human disease and to progressively improving gene delivery technologies. Among these technologies, delivery vectors based on adeno-associated viruses (AAVs) have emerged as safe and effective and, in one recent case, have led to regulatory approval. Although shortcomings in viral vector properties will render extension of such successes to many other human diseases challenging, new approaches to engineer and improve AAV vectors and their genetic cargo are increasingly helping to overcome these barriers.

Capsid↗
PubMed2026

Direct Initiation of Long-Acting Cabotegravir Plus Rilpivirine in People with HIV and Suboptimal Virologic Suppression: A Randomized Trial.

BACKGROUND: Long-acting injectable cabotegravir plus rilpivirine (LA CAB+RPV) is approved for virally suppressed people with human immunodeficiency virus (HIV), but evidence for its use in those with persistent viremia and adherence challenges remains limited. METHODS: We conducted a multicenter, open-label, randomized study involving oral antiretroviral therapy (ART)-experienced people with HIV who had been diagnosed with HIV for at least 12 months and a most recent HIV-1 RNA level of at least 200 copies per milliliter. Participants with resistance-associated mutations to CAB or RPV were excluded. Eligible participants were randomly assigned in a 1:1 ratio to receive immediate LA CAB+RPV or to continue standard oral therapy until Week 24 (delayed switch group). The primary endpoint was the proportion of participants with an HIV-1 RNA level of less than 200 copies per milliliter at Week 24. RESULTS: Of 61 randomized participants, 45 met eligibility criteria and were included in the analysis; 91% were male, and the median baseline HIV-1 RNA was 35,000 copies/mL. At Week 24, viral suppression was achieved in 88.0% (22/25) in the immediate LA group versus 55.0% (11/20) in the delayed switch group (relative risk for failure to achieve viral suppression, 0.27; 95% CI, 0.08-0.86; p = 0.026). The effect of LA CAB+RPV was sustained through Week 52. CONCLUSIONS: Among people with HIV and viremia associated with adherence challenges, immediate initiation of LA CAB+RPV resulted in higher rates of viral suppression than continued oral ART, supporting its use beyond populations with stable suppression.

HIV↗
PubMed1976

Double-blind clinical assessment of ribavirin (virazole) in the prevention of induced infection with type B influenza virus.

The prophylactic effectiveness of oral administration of ribavirin (1-beta-D-ribofuranosyl-1,24-triazole-3-carboxamide, virazole) against artificially induced influenza B infection was evaluated in a double-blind clinical trial. Fifteen seronegative men received ribavirin capsules (600 mg/day in three divided doses), and 15 other men received placebo capsules two days before the inoculation of 6.4 X 10(4) 50% tissue culture infective doses of influenza virus B/Georgia/26/74 and for eight days after challenge. Ten men (69%) in each of the two groups developed mild to severe influenzal illness. Of these, five placebo-treated men developed severe febrile illness, while only one drug-treated man had illness of comparable severity. Illness of moderate severity was observed in three placebo-treated conrols and two drug recipients. There was no difference between the frequencies of isolation of virus or the anitbody responses in the two groups. Ribavirin suppressed signs and symptoms induced by influenza B challenge, but its effectiveness was marginal.

Adult↗
PubMed1977

Clinical trials of adjuvant radiation therapy for breast cancer.

Years ago, radiation therapists conducted randomized clinical trials which showed that regional irradiation significantly reduces local recurrence of breast cancer but does not often affect life span. No new findings challenge these conclusions. Controlled trials in general have lost some credibility, however, as it has become more widely recognized that they are very vulnerable to fallacious reasoning and to simple human error. There is serious concern that some physicians may be unwisely abandoning well tested treatment methods because of the premature dissemination of early results of some trials. Still, many important questions remain that can only be answered by clinical trials, some including radiation therapy. This paper suggests that randomization schemes be incorporated into "routine" medical practice, although only after the most careful deliberation, in order to hasten fuller understanding of old therapeutic methods as well as new ones.

Breast Neoplasms↗
PubMed1979

A controlled clinical trial comparing disodium cromoglycate and ICI 74,917 in extrinsic asthma.

A controlled clinical trial comparing inhalation of disodium cromoglycate (DSCG) and of ICI 74,917 was carried out using a double-placebo technique in thirty-two patients with extrinsic asthma already shown to be reasonably responsive to DSCG. In view of the fact that ICI 74,917 is 300 times more potent than DSCG in inhibiting antigenic challenge in animals a better effect was anticipated from the new drug in the human asthmatic subject. Whilst this was not obtained, there appeared to be no lesser effect than that of DSCG.

Asthma↗
PubMed1978

Effect of a polynucleotide interferon inducer of fungal origin on experimental rhinovirus infection in humans.

A double-stranded RNA of fungal origin (BRL 5907) was given intranasally to volunteers. Apart from mild local irritancy of the higher dosage, the compound was well tolerated. A double-blind placebo-controlled trial of a three-day course (5 mg per day) of BRL 5907 against challenge with rhinovirus type 4 showed that treatment was associated with a delay in onset of symptoms and a reduction in shedding of virus, but the differences were not statistically significant. Low titers of interferon were found in nasal washings.

Adolescent↗