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Quijada, D.

Publications and source records attributed to Quijada, D..

6 recordsLinked to original sources

Targeting CCRL2 enhances therapeutic outcomes in a tuberculosis mouse model

Tuberculosis (TB) remains among the leading infectious causes of death. Due to the limited number of antimicrobials in the TB drug discovery pipeline, interest has developed in host-directed approaches to improve TB treatment outcomes. C-C motif chemokine-like receptor 2 (CCRL2) is a unique seven-transmembrane domain receptor that is upregulated by inflammatory signals and mediates leucocyte migration. However, little is known about its role in the setting of TB infection. Here, we show that Mycobacterium tuberculosis (Mtb) infection increases CCRL2 protein expression in macrophages and in mouse lungs. To target selectively CCRL2-expressing cells in vivo, we developed a novel mouse anti-CCRL2 antibody-drug conjugate (ADC) linked with the cytotoxic drug SG3249. We tested its adjunctive therapeutic efficacy against TB when combined with the first-line regimen for drug-susceptible TB (isoniazid, rifampin, pyrazinamide, ethambutol; RHZE). The anti-CCRL2 ADC treatment potentiated RHZE efficacy in Mtb-infected mice and decreased gross lung inflammation. CCRL2 expression in lung dendritic cells and alveolar macrophages was lower in mice receiving anti-CCRL2 ADC treatment + RHZE compared to those receiving RHZE alone or the control group, although the total innate cell populations did not differ across treatment groups. Interestingly, neutrophils were completely absent in the anti-CCRL2 ADC treatment + RHZE group, unlike in the other treatment groups. IFN-{gamma}+ and IL17-A+ T-cell responses, which are associated with optimal TB control, were also elevated in the anti-CCRL2 ADC treatment + RHZE group. Collectively, our findings suggest that CCRL2-targeting approaches may improve TB treatment outcomes, possibly through selective killing of Mtb-infected innate immune cells.

immunology↗

Therapeutic DNA Vaccine Targeting Mycobacterium tuberculosis Persisters Shortens Curative Tuberculosis Treatment

Mycobacterium tuberculosis (Mtb) is one of the leading infectious causes of death worldwide. There is no available licensed therapeutic vaccine that shortens active tuberculosis (TB) disease drug treatment and prevents relapse, despite the World Health Organizations calls. Here, we show that an intranasal DNA vaccine containing a fusion of the stringent response relMtb gene with the gene encoding the immature dendritic cell-targeting chemokine, MIP-3/CCL20, shortens the duration of curative TB treatment in immunocompetent mice. Compared to the first-line regimen for drug-susceptible TB alone, our novel adjunctive vaccine induced greater RelMtb-specific T-cell responses associated with optimal TB control in spleen, blood, lungs, mediastinal lymph nodes, and bronchoalveolar lavage (BAL) fluid. These responses were sustained, if not augmented, over time. It also triggered more effective dendritic cell recruitment, activation, and colocalization with T cells, implying enhanced crosstalk between innate and adaptive immunity. Moreover, it potentiated a 6-month TB drug-resistant regimen, rendering it effective across treatment regimens, and also showed promising results in CD4+ knockout mice, perhaps due to enhanced Rel-specific CD8+ T-cell responses. Notably, our novel fusion vaccine was also immunogenic in nonhuman primates, the gold standard animal model for TB vaccine studies, eliciting antigen-specific T-cell responses in blood and BAL fluid analogous to those observed in protected mice. Our findings have critical implications for therapeutic TB vaccine clinical development in immunocompetent and immunocompromised populations and may serve as a model for defining immunological correlates of therapeutic vaccine-induced protection. One sentence summaryA TB vaccine shortens curative drug treatment in mice by eliciting strong TB-protective immune responses and induces similar responses in macaques.

immunology↗

Pharmacological inhibition of macrophage triglyceride biosynthesis pathways does not improve Mycobacterium tuberculosis control in infected mice

Triglyceride rich macrophages (foam cells) are a hallmark of necrotic granulomas in tuberculosis, and multiple antimicrobial functions are down-regulated in these cells. In this study, we assessed the ability of two different compounds to reduce triglyceride content and intracellular burden in Mycobacterium tuberculosis (Mtb)-infected macrophages: A-922500 (DGATi), an inhibitor of diacylglycerol acyltransferase 1, an enzyme involved in triglyceride synthesis; and LY2584702 (p70S6Ki), an inhibitor of p70 S6 kinase, a serine/threonine kinase involved in mTORC-1dependent lipid biogenesis. Additionally, we evaluated the adjunctive activity of these inhibitors as host-directed therapies against chronic Mtb infection in C3HeB/FeJ mice. DGATi and p70S6Ki significantly reduced the lipid content and bacillary burden in Mtb-infected human monocyte-derived macrophages. In Mtb-infected mice, each inhibitor reduced the triglyceride content (P[≤] 0.0001) in cells from bronchoalveolar lavage samples. Adjunctive treatment of DGATi with isoniazid and p70S6Ki monotherapy reduced the lipid droplet content (P[≤] 0.05) within lung macrophages of Mtb-infected mice. However, neither inhibitor reduced the lung bacterial burden in Mtb-infected mice alone or in combination with isoniazid, and they did not alter lung inflammation. These findings provide further insights into the role of foam cells in tuberculosis pathogenesis and the utility of interventions targeting these cell populations as adjunctive host-directed therapies.

pharmacology and toxicology↗

The heme oxygenase-1 metalloporphyrin inhibitor stannsoporfin enhances the bactericidal activity of a novel regimen for multidrug-resistant tuberculosis in a murine model

Multidrug-resistant (MDR) Mycobacterium tuberculosis (Mtb) poses significant challenges to global tuberculosis (TB) control efforts. Host-directed therapies (HDT) offer a novel approach for TB treatment by enhancing immune-mediated clearance of Mtb. Prior preclinical studies found that inhibition of heme oxygenase-1 (HO-1), an enzyme involved in heme metabolism, with tin-protoporphyrin IX (SnPP) significantly reduced mouse lung bacillary burden when co-administered with the first-line antitubercular regimen. Here we evaluated the adjunctive HDT activity of a novel HO-1 inhibitor, stannsoporfin (SnMP), in combination with a novel MDR-TB regimen comprising a next-generation diarylquinoline, TBAJ-876 (S), pretomanid (Pa), and a new oxazolidinone, TBI-223 (O) (collectively, SPaO) in Mtb-infected BALB/c mice. After 4 weeks of treatment, SPaO + SnMP 5 mg/kg reduced mean lung bacillary burden by an additional 0.69 log10 (P=0.01) relative to SPaO alone. As early as 2 weeks post-treatment initiation, SnMP adjunctive therapy differentially altered the expression of pro-inflammatory cytokine genes, and CD38, a marker of M1 macrophages. Next, we evaluated the sterilizing potential of SnMP adjunctive therapy in a mouse model of microbiological relapse. After 6 weeks of treatment, SPaO + SnMP 10 mg/kg reduced lung bacterial burdens to 0.71 {+/-} 0.23 log10 CFU, a 0.78 log-fold greater decrease in lung CFU compared to SpaO alone (P=0.005). However, adjunctive SnMP did not reduce microbiological relapse rates after 5 or 6 weeks of treatment. SnMP was well tolerated and did not significantly alter gross or histological lung pathology. SnMP is a promising HDT candidate requiring further study in combination with regimens for drug-resistant TB.

microbiology↗

An intranasal stringent response vaccine targeting dendritic cells as a novel adjunctive therapy against tuberculosis

Lengthy tuberculosis (TB) treatment is required to address the ability of a subpopulation of persistent Mycobacterium tuberculosis (Mtb) to remain in a non-replicating, antibiotic-tolerant state characterized by metabolic remodeling, including induction of the RelMtb-mediated stringent response. We developed a novel therapeutic DNA vaccine construct involving fusion of the relMtb gene with the immature dendritic cell-targeting gene encoding chemokine MIP-3/CCL20. To augment mucosal immune responses, intranasal delivery was also evaluated. We found that the intramuscular MIP-3/relMtb (fusion) vaccine potentiates isoniazid activity more than a similar DNA vaccine expressing relMtb alone in a chronic TB mouse model (absolute reduction of Mtb burden: 0.63 log10 colony-forming units, P=0.0001), inducing pronounced Mtb-protective immune signatures. The intranasal fusion vaccine, an approach combining relMtb fusion to MIP-3 and intranasal delivery, demonstrated the greatest therapeutic effect compared to each approach alone, as evidenced by robust Th1 and Th17 responses systemically and locally and the greatest mycobactericidal activity when combined with isoniazid (absolute reduction of Mtb burden: 1.13 log10, P<0.0001, when compared to the intramuscular vaccine targeting relMtb alone). This DNA vaccination strategy may be a promising adjunctive approach combined with standard therapy to shorten curative TB treatment, and also serve as proof-of-concept for treating other chronic infections.

immunology↗

Sex differences in lung imaging and SARS-CoV-2 antibody responses in a COVID-19 golden Syrian hamster model

In the ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), more severe outcomes are reported in males compared with females, including hospitalizations and deaths. Animal models can provide an opportunity to mechanistically interrogate causes of sex differences in the pathogenesis of SARS-CoV-2. Adult male and female golden Syrian hamsters (8-10 weeks of age) were inoculated intranasally with 105 TCID50 of SARS-CoV-2/USA-WA1/2020 and euthanized at several time points during the acute (i.e., virus actively replicating) and recovery (i.e., after the infectious virus has been cleared) phases of infection. There was no mortality, but infected male hamsters experienced greater morbidity, losing a greater percentage of body mass, developing more extensive pneumonia as noted on chest computed tomography, and recovering more slowly than females. Treatment of male hamsters with estradiol did not alter pulmonary damage. Virus titers in respiratory tissues, including nasal turbinates, trachea, and lungs, and pulmonary cytokine concentrations, including IFN{beta} and TNF, were comparable between the sexes. However, during the recovery phase of infection, females mounted two-fold greater IgM, IgG, and IgA responses against the receptor-binding domain of the spike protein (S-RBD) in both plasma and respiratory tissues. Female hamsters also had significantly greater IgG antibodies against whole inactivated SARS-CoV-2 and mutant S-RBDs, as well as virus neutralizing antibodies in plasma. The development of an animal model to study COVID-19 sex differences will allow for a greater mechanistic understanding of the SARS-CoV-2 associated sex differences seen in the human population. ImportanceMen experience more severe outcomes from COVID-19 than women. Golden Syrian hamsters were used to explore sex differences in the pathogenesis of a human clinical isolate of SARS-CoV-2. After inoculation, male hamsters experienced greater sickness, developed more severe lung pathology, and recovered more slowly than females. Sex differences in disease could not be reversed by estradiol treatment in males and were not explained by either virus replication kinetics or the concentrations of inflammatory cytokines in the lungs. During the recovery period, antiviral antibody responses in the respiratory tract and plasma, including to newly emerging SARS-CoV-2 variants, were greater in females than male hamsters. Greater lung pathology during the acute phase combined with reduced antiviral antibody responses during the recovery phase of infection in males than females illustrate the utility of golden Syrian hamsters as a model to explore sex differences in the pathogenesis of SARS-CoV-2 and vaccine-induced immunity and protection. One Sentence SummaryFollowing SARS-CoV-2 infection, male hamsters experience worse clinical disease and have lower antiviral antibody responses than females.

microbiology↗