Monkey Models of Tuberculosis: Lessons Learned

The use of animal models has been invaluable for studying the pathogenesis ofMycobacterium tuberculosisinfection, as well as for testing the efficacy of vaccines and drug regimens for tuberculosis. Among the applied animal models, nonhuman primates, particularly macaques, share the greatest anatomical and physiological similarities with humans. As such, macaque models have been used for investigating tuberculosis pathogenesis and preclinical testing of drugs and vaccines. This review focuses on published major studies which illustrate how the rhesus and cynomolgus macaques have enriched and may continue to advance the field of global tuberculosis research.

Download Full-text

Characterization of T Cells Specific for CFP-10 and ESAT-6 in Mycobacterium tuberculosis-Infected Mauritian Cynomolgus Macaques

Infection and Immunity ◽

10.1128/iai.01009-16 ◽

2017 ◽

Vol 85 (4) ◽

Cited By ~ 5

Author(s):

Amy Ellis ◽

Alexis Balgeman ◽

Mark Rodgers ◽

Cassaundra Updike ◽

Jaime Tomko ◽

...

Keyword(s):

T Cells ◽

Mycobacterium Tuberculosis ◽

Mhc Class Ii ◽

Nonhuman Primates ◽

Content Type ◽

Host Immune Responses ◽

Cell Responses ◽

Cynomolgus Macaques ◽

Mhc Haplotype

ABSTRACT Nonhuman primates can be used to study host immune responses to Mycobacterium tuberculosis. Mauritian cynomolgus macaques (MCMs) are a unique group of animals that have limited major histocompatibility complex (MHC) genetic diversity, such that MHC-identical animals can be infected with M. tuberculosis. Two MCMs homozygous for the relatively common M1 MHC haplotype were bronchoscopically infected with 41 CFU of the M. tuberculosis Erdman strain. Four other MCMs, which had at least one copy of the M1 MHC haplotype, were infected with a lower dose of 3 CFU M. tuberculosis. All animals mounted similar T-cell responses to CFP-10 and ESAT-6. Two epitopes in CFP-10 were characterized, and the MHC class II alleles restricting them were determined. A third epitope in CFP-10 was identified but exhibited promiscuous restriction. The CFP-10 and ESAT-6 antigenic regions targeted by T cells in MCMs were comparable to those seen in cases of human M. tuberculosis infection. Our data lay the foundation for generating tetrameric molecules to study epitope-specific CD4 T cells in M. tuberculosis-infected MCMs, which may guide future testing of tuberculosis vaccines in nonhuman primates.

Download Full-text

Importance of Confirming Data on theIn VivoEfficacy of Novel Antibacterial Drug Regimens against Various Strains of Mycobacterium tuberculosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05701-11 ◽

2011 ◽

Vol 56 (2) ◽

pp. 731-738 ◽

Cited By ~ 22

Author(s):

Mary A. De Groote ◽

Veronica Gruppo ◽

Lisa K. Woolhiser ◽

Ian M. Orme ◽

Janet C. Gilliland ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Animal Studies ◽

Strain Difference ◽

Drug Combinations ◽

Antibacterial Drug ◽

Preclinical Testing ◽

Content Type ◽

Drug Regimens

ABSTRACTIn preclinical testing of antituberculosis drugs, laboratory-adapted strains ofMycobacterium tuberculosisare usually used both forin vitroandin vivostudies. However, it is unknown whether the heterogeneity ofM. tuberculosisstocks used by various laboratories can result in different outcomes in tests of antituberculosis drug regimens in animal infection models. In head-to-head studies, we investigated whether bactericidal efficacy results in BALB/c mice infected by inhalation with the laboratory-adapted strains H37Rv and Erdman differ from each other and from those obtained with clinical tuberculosis strains. Treatment of mice consisted of dual and triple drug combinations of isoniazid (H), rifampin (R), and pyrazinamide (Z). The results showed that not all strains gave the samein vivoefficacy results for the drug combinations tested. Moreover, the ranking of HRZ and RZ efficacy results was not the same for the two H37Rv strains evaluated. The magnitude of this strain difference also varied between experiments, emphasizing the risk of drawing firm conclusions for human trials based on single animal studies. The results also confirmed that the antagonism seen within the standard HRZ regimen by some investigators appears to be anM. tuberculosisstrain-specific phenomenon. In conclusion, the specific identity ofM. tuberculosisstrain used was found to be an important variable that can change the apparent outcome ofin vivoefficacy studies in mice. We highly recommend confirmation of efficacy results in late preclinical testing against a differentM. tuberculosisstrain than the one used in the initial mouse efficacy study, thereby increasing confidence to advance potent drug regimens to clinical trials.

Download Full-text

Coxiella burnetii Intratracheal Aerosol Infection Model in Mice, Guinea Pigs, and Nonhuman Primates

Infection and Immunity ◽

10.1128/iai.00178-19 ◽

2019 ◽

Vol 87 (12) ◽

Author(s):

A. E. Gregory ◽

E. J. van Schaik ◽

K. E. Russell-Lodrigue ◽

A. P. Fratzke ◽

J. E. Samuel

Keyword(s):

Animal Models ◽

Coxiella Burnetii ◽

Guinea Pigs ◽

Nonhuman Primates ◽

Q Fever ◽

Febrile Illness ◽

Cell Vaccine ◽

Infection Model ◽

Atypical Pneumonia ◽

Content Type

ABSTRACT Coxiella burnetii, the etiological agent of Q fever, is a Gram-negative bacterium transmitted to humans by inhalation of contaminated aerosols. Acute Q fever is often self-limiting, presenting as a febrile illness that can result in atypical pneumonia. In some cases, Q fever becomes chronic, leading to endocarditis that can be life threatening. The formalin-inactivated whole-cell vaccine (WCV) confers long-term protection but has significant side effects when administered to presensitized individuals. Designing new vaccines against C. burnetii remains a challenge and requires the use of clinically relevant modes of transmission in appropriate animal models. We have developed a safe and reproducible C. burnetii aerosol challenge in three different animal models to evaluate the effects of pulmonary acquired infection. Using a MicroSprayer aerosolizer, BL/6 mice and Hartley guinea pigs were infected intratracheally with C. burnetii Nine Mile phase I (NMI) and demonstrated susceptibility as determined by measuring bacterial growth in the lungs and subsequent dissemination to the spleen. Histological analysis of lung tissue showed significant pathology associated with disease, which was more severe in guinea pigs. Infection using large-particle aerosol (LPA) delivery was further confirmed in nonhuman primates, which developed fever and pneumonia. We also demonstrate that vaccinating mice and guinea pigs with WCV prior to LPA challenge is capable of eliciting protective immunity that significantly reduces splenomegaly and the bacterial burden in spleen and lung tissues. These data suggest that these models can have appreciable value in using the LPA delivery system to study pulmonary Q fever pathogenesis as well as designing vaccine countermeasures to C. burnetii aerosol transmission.

Download Full-text

Developing New Drugs for Mycobacterium tuberculosis Therapy: What Information Do We Get from Preclinical Animal Models?

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01376-20 ◽

2020 ◽

Vol 64 (12) ◽

Author(s):

G. L. Drusano ◽

Brandon Duncanson ◽

C. A. Scanga ◽

S. Kim ◽

S. Schmidt ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Animal Models ◽

Scale Up ◽

New Drugs ◽

Model Systems ◽

Infection Model ◽

New Agents ◽

Content Type ◽

Preclinical Animal Models ◽

The Impact

ABSTRACT Preclinical animal models of infection are employed to develop new agents but also to screen among molecules to rank them. There are often major differences between human pharmacokinetic (PK) profiles and those developed by animal models of infection, and these may lead to substantial differences in efficacy relative to that seen in humans. Linezolid is a repurposed agent employed to great effect for therapy of Mycobacterium tuberculosis. In this study, we used the hollow-fiber infection model (HFIM) to evaluate the impact of different pharmacokinetic profiles of mice and nonhuman primates (NHP) versus humans on bacterial cell kill as well as resistance suppression. We examined both plasma and epithelial lining fluid (ELF) profiles. We examined simulated exposures equivalent to 600 mg and 900 mg daily of linezolid in humans. For both plasma and ELF exposures, the murine PK profile provided estimates of effect that were biased low relative to human and NHP PK profiles. Mathematical modeling identified a linkage between minimum concentrations (Cmin) and bacterial kill and peak concentrations (Cpeak) and resistance suppression, with the latter being supported by a prospective validation study. Finding new agents with novel mechanisms of action against M. tuberculosis is difficult. It would be a tragedy to discard a new agent because of a biased estimate of effect in a preclinical animal system. The HFIM provides a system to benchmark evaluation of new compounds in preclinical animal model systems against human PK effects (species scale-up estimates of PK), to safeguard against unwarranted rejection of promising new agents.

Download Full-text

Effects of B Cell Depletion on Early Mycobacterium tuberculosis Infection in Cynomolgus Macaques

Infection and Immunity ◽

10.1128/iai.00083-16 ◽

2016 ◽

Vol 84 (5) ◽

pp. 1301-1311 ◽

Cited By ~ 47

Author(s):

Jiayao Phuah ◽

Eileen A. Wong ◽

Hannah P. Gideon ◽

Pauline Maiello ◽

M. Teresa Coleman ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

B Cells ◽

B Cell ◽

Humoral Immunity ◽

Nonhuman Primates ◽

Acute Infection ◽

Cell Depletion ◽

B Cell Depletion ◽

Content Type ◽

The Impact

Although recent studies in mice have shown that components of B cell and humoral immunity can modulate the immune responses againstMycobacterium tuberculosis, the roles of these components in human and nonhuman primate infections are unknown. The cynomolgus macaque (Macaca fascicularis) model ofM. tuberculosisinfection closely mirrors the infection outcomes and pathology in human tuberculosis (TB). The present study used rituximab, an anti-CD20 antibody, to deplete B cells inM. tuberculosis-infected macaques to examine the contribution of B cells and humoral immunity to the control of TB in nonhuman primates during the acute phase of infection. While there was no difference in the overall pathology, disease profession, and clinical outcome between the rituximab-treated and untreated macaques in acute infection, analyzing individual granulomas revealed that B cell depletion resulted in altered local T cell and cytokine responses, increased bacterial burden, and lower levels of inflammation. There were elevated frequencies of T cells producing interleukin-2 (IL-2), IL-10, and IL-17 and decreased IL-6 and IL-10 levels within granulomas from B cell-depleted animals. The effects of B cell depletion varied among granulomas in an individual animal, as well as among animals, underscoring the previously reported heterogeneity of local immunologic characteristics of tuberculous granulomas in nonhuman primates. Taken together, our data clearly showed that B cells can modulate the local granulomatous response inM. tuberculosis-infected macaques during acute infection. The impact of these alterations on disease progression and outcome in the chronic phase remains to be determined.

Download Full-text

Deficiency of Double-Strand DNA Break Repair Does Not Impair Mycobacterium tuberculosis Virulence in Multiple Animal Models of Infection

Infection and Immunity ◽

10.1128/iai.01540-14 ◽

2014 ◽

Vol 82 (8) ◽

pp. 3177-3185 ◽

Cited By ~ 11

Author(s):

Brook E. Heaton ◽

Daniel Barkan ◽

Paola Bongiorno ◽

Petros C. Karakousis ◽

Michael S. Glickman

Keyword(s):

Dna Damage ◽

Mycobacterium Tuberculosis ◽

Animal Models ◽

Bacterial Load ◽

Dna Breaks ◽

Dsb Repair ◽

Content Type ◽

Dna Break ◽

Repair Systems ◽

Double Strand Dna

ABSTRACTMycobacterium tuberculosispersistence within its human host requires mechanisms to resist the effector molecules of host immunity, which exert their bactericidal effects through damaging pathogen proteins, membranes, and DNA. Substantial evidence indicates that bacterial pathogens, includingM. tuberculosis, require DNA repair systems to repair the DNA damage inflicted by the host during infection, but the role of double-strand DNA break (DSB) repair systems is unclear. Double-strand DNA breaks are the most cytotoxic form of DNA damage and must be repaired for chromosome replication to proceed.M. tuberculosiselaborates three genetically distinct DSB repair systems: homologous recombination (HR), nonhomologous end joining (NHEJ), and single-strand annealing (SSA). NHEJ, which repairs DSBs in quiescent cells, may be particularly relevant toM. tuberculosislatency. However, very little information is available about the phenotype of DSB repair-deficientM. tuberculosisin animal models of infection. Here we testedM. tuberculosisstrains lacking NHEJ (a ΔkuΔligDstrain), HR (a ΔrecAstrain), or both (a ΔrecAΔkustrain) in C57BL/6J mice, C3HeB/FeJ mice, guinea pigs, and a mouse hollow-fiber model of infection. We found no difference in bacterial load, histopathology, or host mortality between wild-type and DSB repair mutant strains in any model of infection. These results suggest that the animal models tested do not inflict DSBs on the mycobacterial chromosome, that other repair pathways can compensate for the loss of NHEJ and HR, or that DSB repair is not required forM. tuberculosispathogenesis.

Download Full-text

A Mycobacterium tuberculosis Cytochrome bd Oxidase Mutant Is Hypersensitive to Bedaquiline

mBio ◽

10.1128/mbio.01275-14 ◽

2014 ◽

Vol 5 (4) ◽

Cited By ~ 48

Author(s):

Michael Berney ◽

Travis E. Hartman ◽

William R. Jacobs

Keyword(s):

Mycobacterium Tuberculosis ◽

Proton Pumping ◽

Major Drawback ◽

Content Type ◽

Cytochrome Bd ◽

New Drug ◽

Long Duration ◽

Bacterial Enzyme ◽

Drug Regimens ◽

Cytochrome Bd Oxidase

ABSTRACT The new medicinal compound bedaquiline (BDQ) kills Mycobacterium tuberculosis by inhibiting F1Fo-ATP synthase. BDQ is bacteriostatic for 4 to 7 days and kills relatively slowly compared to other frontline tuberculosis (TB) drugs. Here we show that killing with BDQ can be improved significantly by inhibiting cytochrome bd oxidase, a non-proton-pumping terminal oxidase. BDQ was instantly bactericidal against a cytochrome bd oxidase null mutant of M. tuberculosis, and the rate of killing was increased by more than 50%. We propose that this exclusively bacterial enzyme should be a high-priority target for new drug discovery. IMPORTANCE A major drawback of current TB chemotherapy is its long duration. New drug regimens with rapid killing kinetics are desperately needed. Our study demonstrates that inhibition of a nonessential bacterial enzyme greatly improves the efficacy of the latest TB drug bedaquiline and emphasizes that screening for compounds with synergistic killing mechanisms is a promising strategy.

Download Full-text

Experimental Mycobacterium tuberculosis Infection of Cynomolgus Macaques Closely Resembles the Various Manifestations of Human M. tuberculosis Infection

Infection and Immunity ◽

10.1128/iai.71.10.5831-5844.2003 ◽

2003 ◽

Vol 71 (10) ◽

pp. 5831-5844 ◽

Cited By ~ 297

Author(s):

Saverio V. Capuano ◽

Denise A. Croix ◽

Santosh Pawar ◽

Angelica Zinovik ◽

Amy Myers ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Immune Responses ◽

Nonhuman Primates ◽

Low Dose ◽

Latent Tuberculosis ◽

Tuberculosis Infection ◽

Mycobacterium Tuberculosis Infection ◽

Full Spectrum ◽

Tuberculin Skin Test Conversion ◽

Cynomolgus Macaques

ABSTRACT Nonhuman primates were used to develop an animal model that closely mimics human Mycobacterium tuberculosis infection. Cynomolgus macaques were infected with low doses of virulent M. tuberculosis via bronchoscopic instillation into the lung. All monkeys were successfully infected, based on tuberculin skin test conversion and peripheral immune responses to M. tuberculosis antigens. Progression of infection in the 17 monkeys studied was variable. Active-chronic infection, observed in 50 to 60% of monkeys, was characterized by clear signs of infection or disease on serial thoracic radiographs and in other tests and was typified by eventual progression to advanced disease. Approximately 40% of monkeys did not progress to disease in the 15 to 20 months of study, although they were clearly infected initially. These monkeys had clinical characteristics of latent tuberculosis in humans. Low-dose infection of cynomolgus macaques appears to represent the full spectrum of human M. tuberculosis infection and will be an excellent model for the study of pathogenesis and immunology of this infection. In addition, this model will provide an opportunity to study the latent M. tuberculosis infection observed in ∼90% of all infected humans.

Download Full-text

Medical, Genomic, and Evolutionary Aspects of the Peptide Sharing between Pathogens, Primates, and Humans

Global Medical Genetics ◽

10.1055/s-0040-1716334 ◽

2020 ◽

Vol 07 (02) ◽

pp. 064-067 ◽

Cited By ~ 1

Author(s):

Darja Kanduc ◽

Yehuda Shoenfeld

Keyword(s):

Animal Models ◽

Rhesus Macaque ◽

Nonhuman Primates ◽

Molecular Mimicry ◽

Homo Sapiens ◽

Point Of View ◽

Preclinical Testing ◽

Medical Genomic ◽

Scientific Challenge ◽

Evolutionary Aspects

AbstractComparing mammalian proteomes for molecular mimicry with infectious pathogens highlights the highest levels of heptapeptide sharing between pathogens and human, murine, and rat proteomes, while the peptide sharing level is minimal (or absent) with proteomes from nonhuman primates such as gorilla, chimpanzee, and rhesus macaque. From the medical point of view, the data might be useful to clinicians and vaccinologists to develop and evaluate immunomodulatory and immunotherapeutic approaches. As a matter of fact, primates seem to be unreliable animal models for revealing potential autoimmune events in preclinical testing of immunotherapies. In terms of genomics, the scarce or absent peptide sharing between pathogens and primates versus the massive peptide sharing existing between pathogens and humans lets foresee mechanisms of pathogen sequence insertion/deletion/alteration that have differently operated in mammals over evolutionary timescales. Why and how the human genome has been colonized by pathogen sequences and why and how primates escaped such a colonization appears to be the new scientific challenge in our efforts to understand not only the origin of Homo sapiens but also his autoimmune diseasome.

Download Full-text

Mutations in fbiD (Rv2983) as a Novel Determinant of Resistance to Pretomanid and Delamanid in Mycobacterium tuberculosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01948-20 ◽

2020 ◽

Vol 65 (1) ◽

pp. e01948-20

Author(s):

Dalin Rifat ◽

Si-Yang Li ◽

Thomas Ioerger ◽

Keshav Shah ◽

Jean-Philippe Lanoix ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Clinical Evidence ◽

Clinical Samples ◽

Loss Of Function ◽

Wild Type ◽

Content Type ◽

Solid Media ◽

High Level ◽

Level Resistance

ABSTRACTThe nitroimidazole prodrugs delamanid and pretomanid comprise one of only two new antimicrobial classes approved to treat tuberculosis (TB) in 50 years. Prior in vitro studies suggest a relatively low barrier to nitroimidazole resistance in Mycobacterium tuberculosis, but clinical evidence is limited to date. We selected pretomanid-resistant M. tuberculosis mutants in two mouse models of TB using a range of pretomanid doses. The frequency of spontaneous resistance was approximately 10−5 CFU. Whole-genome sequencing of 161 resistant isolates from 47 mice revealed 99 unique mutations, of which 91% occurred in 1 of 5 genes previously associated with nitroimidazole activation and resistance, namely, fbiC (56%), fbiA (15%), ddn (12%), fgd (4%), and fbiB (4%). Nearly all mutations were unique to a single mouse and not previously identified. The remaining 9% of resistant mutants harbored mutations in Rv2983 (fbiD), a gene not previously associated with nitroimidazole resistance but recently shown to be a guanylyltransferase necessary for cofactor F420 synthesis. Most mutants exhibited high-level resistance to pretomanid and delamanid, although Rv2983 and fbiB mutants exhibited high-level pretomanid resistance but relatively small changes in delamanid susceptibility. Complementing an Rv2983 mutant with wild-type Rv2983 restored susceptibility to pretomanid and delamanid. By quantifying intracellular F420 and its precursor Fo in overexpressing and loss-of-function mutants, we provide further evidence that Rv2983 is necessary for F420 biosynthesis. Finally, Rv2983 mutants and other F420H2-deficient mutants displayed hypersusceptibility to some antibiotics and to concentrations of malachite green found in solid media used to isolate and propagate mycobacteria from clinical samples.

Download Full-text