Robert Koch and the pressures of scientific research: tuberculosis and tuberculin

Historical examination of tuberculosis; from ancient affliction to modern challenges

Tuberculosis (TB), white plague, many other definitions is an ancient deadly infection that humans dealt with after creation. The first hypothesis refers to 150 million years ago about the appearance of TB in the Jurassic era before human creation, but documents show 9000 years ago for first appearance in human society. In 1882, Robert Koch was able to identify and describe the best possible agent of TB. After the discovery of TB's agent [Mycobacterium tuberculosis], progress was made in diagnosis and treatment rapidly, and invasive operations such as surgery were replaced with drug treatment and chemical compounds hired for treatment that were so effective before drug resistance occurrence. In this review authors done their tries to describe all aspects of TB [identification, epidemics, diagnostics, drug development, etc.] in history from ancient records to the present condition and give insight into the future of TB ending in 2030 and 2050.

TB prevention and immunization in pediatrics

Tuberculosis (TB) is one of the main contributors to global mortality and morbidity. Prevalence of TB is more in developing countries. It is one of the airborne diseases that has always been a major health problem. It is caused by organisms of the Mycobacterium tuberculosis (MTB) complex affecting different organ systems. The proverb prevention is better than cure best applies to TB and it has been practiced from ancient periods. However, modalities of prevention have varied much depending upon the advancement in research and technology. TB preventive practice reduces the load of TB significantly and it was used as the theme for world TB Day for the year 2013. Bacille Calmette-Guérin (BCG) vaccination is one of the modalities to prevent TB and it's been practiced for decades with a lot of modifications from synthesis, schedule and method of administration. BCG mainly prevents serious TB with a less known effect on TB prevention. Other uses of BCG vaccination are being studied. In the modern era, heterologous effects of BCG vaccination have brought BCG once again into the limelight. TB prevention strategies start from basic health education and vaccination. Newer vaccines are under trial to improve the efficacy of TB vaccination and yet to be used for general practice. Prevention and immunization against TB have been modified in immunocompromised children. The concept of drug resistance has to be kept in mind before using anti tubercular drugs without any bacteriological evidence for tuberculosis. National Tuberculosis Elimination Programme (NTEP) focuses on contact tracing and treatment of latent TB infection as a resort to prevent further spread of TB in India. This review article has been authored following an exhaustive examination of the existing literature, with the aim of enhancing comprehension regarding tuberculosis prevention and immunization.

Identification of potent indolizine derivatives against Mycobacterial tuberculosis: In vitro anti-TB properties, in silico target validation, molecular docking and dynamics studies

In the current study, two sets of compounds: (E)-1-(2-(4-substitutedphenyl)-2-oxoethyl)-4-((hydroxyimino)methyl)pyridinium derivatives (3a-3e); and (E)-3-(substitutedbenzoyl)-7-((hydroxyimino)methyl)-2-substitutedindolizine-1-carboxylate derivatives (5a-5j), were synthesized and biologically evaluated against two strains of Mycobacterial tuberculosis (ATCC 25177) and multi-drug resistant (MDR) strains. Further, they were also tested in vitro against the mycobacterial InhA enzyme. The in vitro results showed excellent inhibitory activities against both MTB strains and compounds 5a-5j were found to be more potent, and their MIC values ranged from 5 to 16 μg/mL and 16-64 μg/mL against the M. tuberculosis (ATCC 25177) and MDR-TB strains, respectively. Compound 5h with phenyl and 4-fluorobenzoyl groups attached to the 2- and 3-position of the indolizine core was found to be the most active against both strains with MIC values of 5 μg/mL and 16 μg/mL, respectively. On the other hand, the two sets of compounds showed weak to moderate inhibition of InhA enzyme activity that ranged from 5 to 17 % and 10-52 %, respectively, with compound 5f containing 4-fluoro benzoyl group attached to the 3-position of the indolizine core being the most active (52 % inhibition of InhA). Unfortunately, there was no clear correlation between the InhA inhibitory activity and MIC values of the tested compounds, indicating the probability that they might have different modes of action other than InhA inhibition. Therefore, a computational investigation was conducted by employing molecular docking to identify their putative drug target(s) and, consequently, understand their mechanism of action. A panel of 20 essential mycobacterial enzymes was investigated, of which β-ketoacyl acyl carrier protein synthase I (KasA) and pyridoxal-5'-phosphate (PLP)-dependent aminotransferase (BioA) enzymes were revealed as putative targets for compounds 3a-3e and 5a-5j, respectively. Moreover, in silico ADMET predictions showed adequate properties for these compounds, making them promising leads worthy of further optimization.

Mycobacterium tuberculosis: immune response, biomarkers, and therapeutic intervention

Although tuberculosis (TB) is an infectious disease, the progression of the disease following Mycobacterium tuberculosis (MTB) infection is closely associated with the host's immune response. In this review, a comprehensive analysis of TB prevention, diagnosis, and treatment was conducted from an immunological perspective. First, we delved into the host's immune response mechanisms against MTB infection as well as the immune evasion mechanisms of the bacteria. Addressing the challenges currently faced in TB diagnosis and treatment, we also emphasized the importance of protein, genetic, and immunological biomarkers, aiming to provide new insights for early and personalized diagnosis and treatment of TB. Building upon this foundation, we further discussed intervention strategies involving chemical and immunological treatments for the increasingly critical issue of drug-resistant TB and other forms of TB. Finally, we summarized TB prevention, diagnosis, and treatment challenges and put forward future perspectives. Overall, these findings provide valuable insights into the immunological aspects of TB and offer new directions toward achieving the WHO's goal of eradicating TB by 2035.

Oral and maxillofacial tuberculosis: A systematic review

OBJECTIVES

This study aimed to analyze the demographic, clinical, histopathological, diagnosis, treatment, and follow-up data on the occurrence of oral and maxillofacial tuberculosis (OMTB).

METHODS

Electronic searches without publication date restrictions were undertaken in four databases. Case reports and case series describing the occurrence of OMTB were included. Critical evaluation of studies was done using the Joanna Briggs Institute - University of Adelaide tool for case reports or case series.

RESULTS

A total of 217 studies were included in the qualitative synthesis, for a total of 301 cases of OMTB. Of these patients, 192 (63.7%) were male, with an average age of 39.6 ± 19.8 (15 months to 81 years). The tongue (n = 80/26.6%) represented the most common affected site, followed by the mandible (n = 43/14.3%). The clinical presentation consisted mainly of a painful ulcerated lesion (n = 156/56.5%). Histopathological analysis showed a granulomatous inflammation in most cases (n = 156/63.1%). The main diagnostic methods used were sputum test (n = 53/26.8%), culture (n = 49/24.7%) and purified protein derivative (PPD), or Mantoux test (n = 49/24.7%). Antituberculosis therapy was used in 244 cases (100.0%) and 5.2% of patients died.

CONCLUSIONS

This systematic review provided clinical, demographic data and information about diagnostic methods of OMTB lesions and served as an important guide to assist health professionals in the early diagnosis of these lesions.

The animal model of human disease as a core concept of medical research: Historical cases, failures, and some epistemological considerations

This article uses four historical case studies to address epistemological issues related to the animal model of human diseases and its use in medical research on human diseases. The knowledge derived from animal models is widely assumed to be highly valid and predictive of reactions by human organisms. In this contribution, I use three significant historical cases of failure (ca. 1890, 1960, 2006), and a closer look at the emergence of the concept around 1860/70, to elucidate core assumptions related to the specific practices of animal-human knowledge transfer, and to analyze the explanations provided by historical actors after each of the failures. Based on these examples, I argue that the epistemological status of the animal model changed from that of a helpful methodological tool for addressing specific questions, but with precarious validity, to an obligatory method for the production of strong knowledge on human diseases. As a result, there now exists a culture of biomedical research in human disease that, for more than a century, has taken the value of this methodological tool as self-evident, and more or less beyond question.

Vaccine Efficacy Denial: A Growing Concern Affecting Modern Science, and Impacting Public Health

BACKGROUND

The discovery of the vaccination technique has been revealed by Edward Jenner in 1796: undoubtedly, it represents the first scientific attempt to control an infectious disease by vaccines, followed by other important studies carried out by Pasteur and Koch, and Sabin, who developed the first technique to attenuate the virus. In recent decades, numerous scholars have begun to create dangerous theories against the effectiveness of vaccines through scientifically invalid or fraudulent studies.

AIM

This critical review of the literature aims to analyse the main factors that have undermined the credibility of vaccines in the general population, to disprove false information and, on the other hand, emphasize the benefits of vaccines over the last 200 years.

DISCUSSIONS

Unfortunately, several studies have been carried out without the proper scientific rigour. The most impacting example is the study published by Andrew Wakefield in the Lancet journal that tried to correlate vaccines with the development of autism: this publication was withdrawn from the journal a few years after its publication, but the impact of incorrect scientific studies, fake news, and ambiguous healthcare policies has led to an adverse general opinion about the effectiveness of vaccines.

CONCLUSION

The excess of uncontrolled information is a serious concerning in the Coronavirus pandemic. The modern science must tackle this problem with a better willingness to communicate even the clinical studies to those people not able to understand the medical information autonomously. Nevertheless, a reliable science must also limit the dissemination of studies that do not meet the basic criteria of a methodological rigor and certainty of results, in order not to feed confusion in the scientific community.

In Silico Characterization and Virtual Screening of GntR/HutC Family Transcriptional Regulator MoyR: A Potential Monooxygenase Regulator in Mycobacterium tuberculosis

Simple Summary

In an era where the world faces new diseases and pathogens, another emerging challenge is neglected pathogens becoming more notorious. Transcriptional regulators play a vital role in the pathogenesis and survival of these pathogens. Hence, characterizing transcriptional regulators, either in vitro or in silico, is of great importance. Here, we present the first structural characterization of a GntR/HutC regulator in Mycobacterium tuberculosis via in silico methods. We have suggested its possible role and potential as a drug target as well as identified possible drug leads that can be used for further improvements.

Abstract

Mycobacterium tuberculosis is a well-known pathogen due to the emergence of drug resistance associated with it, where transcriptional regulators play a key role in infection, colonization and persistence. The genome of M. tuberculosis encodes many transcriptional regulators, and here we report an in-depth in silico characterization of a GntR regulator: MoyR, a possible monooxygenase regulator. Homology modelling provided a reliable structure for MoyR, showing homology with a HutC regulator DasR from Streptomyces coelicolor. In silico physicochemical analysis revealed that MoyR is a cytoplasmic protein with higher thermal stability and higher pI. Four highly probable binding pockets were determined in MoyR and the druggability was higher in the orthosteric binding site consisting of three conserved critical residues: TYR179, ARG223 and GLU234. Two highly conserved leucine residues were identified in the effector-binding region of MoyR and other HutC homologues, suggesting that these two residues can be crucial for structure stability and oligomerization. Virtual screening of drug leads resulted in four drug-like compounds with greater affinity to MoyR with potential inhibitory effects for MoyR. Our findings support that this regulator protein can be valuable as a therapeutic target that can be used for developing drug leads.

Multidrug resistant tuberculosis - Diagnostic challenges and its conquering by nanotechnology approach - An overview

One of the leading killer diseases that target the parenchymal tissues of lungs is Tuberculosis. Although antimycobacterial drugs are available, there are increased incidences of drug resistance encountered in Mycobacterium sp. They have been categorized into MDR (Multidrug resistant) and XDR (Extensively drug-resistant) strains exhibiting resistance toward successive treatment regimen. This situation threatens the futuristic containment of TB with the dearth of anti-TB drugs. Nanotechnology, the emerging multidisciplinary science has presented an excellent opportunity for timely and accurate diagnosis and discrimination of Mycobacteria via its unique physio-chemical and optical characteristics. The delayed and misdiagnosis of TB and lack of sensitive diagnostic method(s) has seen a paradigm shift toward nanoparticulate system for improved diagnosis, drug delivery and reduced treatment frequency. This review article highlights the evolution of tuberculosis and its transformation to multidrug resistant strain. Further, the conventional methods for diagnosing TB and the challenges encountered in their analytical performance have been highlighted and the strategies to overcome those challenges have been briefly discussed. Smart approaches encompassing metal nanoparticles, Quantum Dots (QDs) and Field Effect Transistors (FET) based biosensor for accurate diagnosis have been critically reviewed. A decade long state-of-the-art knowledge on TB nanodiagnostics, fabrication concepts and performance characteristics has been reviewed.

The impact of COVID-19 on tuberculosis: challenges and opportunities

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a seafood market in Wuhan, China, has ushered in a new era. It transformed into a pandemic, seized global attention, and was the biggest highlight of the year 2020. The SARS-CoV-2 outbreak has jeopardized health systems and greatly affected socioeconomic parameters. With global focus on fighting this unpredictable fight with this new virus, the biggest chronic infectious killer, mycobacterium tuberculosis (M. tb), was hugely affected from this shift in attention. Due to certain similarities in the behavior of the two infectious agents, there have been inevitable consequences. On one hand, administrative measures to contain SARS-CoV-2 have simultaneously led to a breaking in the chain of tuberculosis (TB) management. Consequently, a regression occurred in the milestones achieved in the battle against TB. On the other hand, the same measures and heightened hygiene awareness has helped to decrease the spread of the TB bacilli. With an improved understanding of the interrelations and the outcomes noticed in 2020, we can better gear ourselves to develop a more sophisticated and robust strategy to tilt the balance against TB. Keeping this in mind, in this review we aim to discuss in detail the implications of SARS-CoV-2 on an already unwavering health hazard: TB.

Tuberculosis: a timeless challenge for medicine

This overview shows how tuberculosis has represented and still represents a continuous challenge for Medicine. Starting from the dawn of medicine, when tuberculosis was called “phthisis” by Hippocrates, passing through the discovery of the tubercles and the creation of the word “tuberculosis”, following the application of the anatomo-clinical method, until the discovery of a microscopic enemy: Mycobacterium tuberculosis. The progressive discovery of the pathological basis of tuberculosis has allowed to devise important therapeutic strategies in Pre-Antibiotic and Post-Antibiotic Era. In particular, “antibiotic therapy” had to be the end of the challenge between man and tuberculosis. However it was only an illusion. Despite progress in care and prevention, tuberculosis remains one of the world’s leading causes of ill-health and the first cause of death from infectious disease. Nowadays, the drug resistance, individuals with immune deficiencies, the ageing and globalization are just some of the causes responsible for the increasing of the challenge between man and tuberculosis.

"How was tuberculosis known to the world?"

Tuberculosis is a well-known disease in the Indian subcontinent. This disease always poses challenges in front of the clinician for its proper treatment. However, its discovery was equally challenging. It took a great effort of many clinicians after which this disease was known to the world. History of tuberculosis is not only extensive but dramatic as well.

The history of tuberculosis: from the first historical records to the isolation of Koch's bacillus

Tuberculosis (TB) is a contagious, infectious disease, due to Mycobacterium tuberculosis (MT) that has always been a permanent challenge over the course of human history, because of its severe social implications. It has been hypothesized that the genus Mycobacterium originated more than 150 million years ago. In the Middle Ages, scrofula, a disease affecting cervical lymph nodes, was described as a new clinical form of TB. The illness was known in England and France as "king's evil", and it was widely believed that persons affected could heal after a royal touch. In 1720, for the first time, the infectious origin of TB was conjectured by the English physician Benjamin Marten, while the first successful remedy against TB was the introduction of the sanatorium cure. The famous scientist Robert Koch was able to isolate the tubercle bacillus and presented this extraordinary result to the society of Physiology in Berlin on 24 March 1882. In the decades following this discovery, the Pirquet and Mantoux tuberculin skin tests, Albert Calmette and Camille Guérin BCG vaccine, Selman Waksman streptomycin and other anti-tuberculous drugs were developed.

Targeting multidrug-resistant tuberculosis (MDR-TB) by therapeutic vaccines

Tuberculosis (TB) has scourged humankind for millennia, and latent infection affects nearly one-third of today's world population. The emergence of multidrug-resistant (MDR)-TB is a major global threat and reflects treatment failure of drug-sensitive disease. MDR-TB management is a burden for patients and society; success rates are unacceptably low with prolonged treatment duration. Mycobacterium tuberculosis (Mtb) possesses the ability to transform into a dormant state in which it can persist in the face of antimicrobial treatment and host defense. This sub-population of persisters is largely responsible for lengthy and difficult treatment. Targeting persistent bacilli could eventually improve the treatment success rate (currently 50-65 %) and shorten duration of treatment. A subset of therapies in the pipeline, termed therapeutic vaccines, use the host immune response to attack Mtb. The historical occurrence of an exacerbated host response has resulted in a negative perception of therapeutic vaccines. Thus, a renewed concept of immunotherapy is needed. We review current perspectives of immunotherapy in MDR-TB based on the knowledge of TB immunology and briefly discuss the profiles of several therapeutic vaccine products.

Robert Koch and the 'golden age' of bacteriology

Robert Koch's discovery of the anthrax bacillus in 1876 launched the field of medical bacteriology. A 'golden age' of scientific discovery ensued. A century after Koch's death, we remember his life and work.

Packaging BCG: standardizing an anti-tuberculosis vaccine in interwar Europe

Using the example of the anti-tuberculosis vaccine BCG during the 1920s and 1930s, this article asks how a labile laboratory-modified bacteria was transformed into a genuine standard vaccine packaged and commercialized as a pharmaceutical product. At the center of the analysis lies the notion of standardization inquiring why and how a local laboratory process with standard operating procedures (SOPs) reached its limits and was transformed when the product faced international distribution. Moving from Paul Ehrlich's initial technological notion of Wertbestimmung referring to a practice physiologically testing the effects of ill-defined antitoxins, the concept of standardization is extended to pharmaceutical and economical meanings implying quality control for biological therapeutic agents produced by a variety of industrial entrepreneurs. Following the request for product uniformity, two ways to maintain levels of compatibility and commonality are depicted opposing SOPs and end-product control. Furthermore, standardization is understood as a spiral, never ending process where progressive transformation of the vaccine in its production and medical uses periodically recreated the necessity of standardization. Developments analyzed are thus understood as a stabilization process aligning laboratory settings, products, and practices with medical theories and practices through technical, bureaucratic, and organizational systems. A paradox of the analysis is that standardization as a historical phenomenon and moment in the history of drug development was initially linked to a problem of under-determination of what was to be standardized and to a knowledge gap before it could become a central concept for quality control.

Locating therapeutic vaccines in nineteenth-century history

This essay places some therapeutic vaccines, including particularly the diphtheria antitoxin, into their larger historical context of the late nineteenth century. As industrially produced drugs, these vaccines ought to be seen in connection with the structural changes in medicine and pharmacology at the time. Given the spread of industrial culture and technology into the field of medicine and pharmacology, therapeutic vaccines can be understood as boundary objects that required and facilitated communication between industrialists, medical researchers, public health officials, and clinicians. It was in particular in relation to evaluation and testing for efficacy in animal models that these medicines became a model for twentieth-century medicine. In addition, these medicines came into being as a parallel invention in two very distinct local cultures of research: the Institut Pasteur in Paris and the Institut für Infektionskrankheiten in Berlin. While their local cultural origins were plainly visible, the medicines played an important role in the alignment of the methods and objects that took place in bacteriology research in France and Germany in the 1890s. This article assesses the two locally specific regimes for control in France and in Imperial Germany. In France the Institut Pasteur, building on earlier successful vaccines, enjoyed freedom from scrutinizing control. The tight and elaborate system of control that evolved in Imperial Germany is portrayed as being reliant on experiences that were drawn from the dramatic events that surrounded the launching of a first example of so-called "bacteriological medicine," tuberculin, in 1890.

Breaking the ties: epistemic significance, bacilli, and underdetermination

One premise of the underdetermination argument is that entailment of evidence is the only epistemic constraint on theory-choice. I argue that methodological rules can be epistemically significant, both with respect to observables and unobservables. Using an example from the history of medicine -- Koch's 1882 discovery of tuberculosis bacteria -- I argue that even anti-realists ought to accept that these rules can break the tie between theories that are allegedly underdetermined. I then distinguish two types of underdetermination and argue that anti-realists, in order to maintain the underdetermination argument, need to do more than show that theories are empirically equivalent: they need to show that a certain kind of underdetermination obtains.

Robert Koch and the white death: from tuberculosis to tuberculin

The German medical bacteriologist Robert Koch is commonly considered one of the founding fathers of medical bacteriology. His investigations into the aetiology of tuberculosis uncovered the pathogen of this condition, the tubercle bacillus today known as Mycobacterium tuberculosis, in 1882. This work can be seen as a cornerstone of contemporary medical bacteriology, its technologies and methods. It has often been asked how such successful research connected to the tuberculin episode of 1890/91, when Koch produced a medicine for that disease, which spectacularly failed when applied in practice. The analysis concentrates on the path of mostly experimental investigations which Koch followed between 1882 and 1890. From Koch's laboratory notes it becomes clear that tuberculin therapy did in fact work in Koch's laboratory, even though it failed to do so almost anywhere else. The clue to this contradictory picture lies in the peculiar nature of Koch's understanding of tuberculosis as a disease e.g. his reliance an animal experiments, which essentially differed from what many of his contemporaries held as essentials of that condition.

Robert Koch: Nobel laureate and controversial figure in tuberculin research

Tuberculosis has been a major cause of death for centuries. Likewise, anthrax has posed a deadly threat to both farm animals and humans and today poses a threat as a weapon of biological warfare. Cholera, which wreaked havoc in the East and threatened to enter Europe, also posed a deadly threat. The causes of these diseases remained mysteries for centuries. Nobel laureate Robert Koch (1843-1910), often called the founder of medical bacteriology, is credited with discovering the tubercle bacillus, Mycobacterium tuberculosis; with demonstrating for the first time in history the life cycle of the anthrax bacillus under controlled in vitro conditions; and with identifying Vibrio cholorae as the cause of cholera. In later life, he also was at the center of several controversies. This article provides a brief summary of Koch's exploration into bacteriology and, especially, his experience with tuberculosis and the controversies that developed in the latter part of his life, as well as his childhood and early adult years and the development of his now well-known "postulates."

Before there were standards: the role of test animals in the production of empirical generality in physiology

After 1900, the selective breeding of a few standard animals for research in the life sciences changed the way science was done. Among the pervasive changes was a transformation in scientists' assumptions about relationship between diversity and generality. Examination of the contents of two prominent physiology journals between 1885 and 1900, reveals that scientists used a diverse array of organisms in empirical research. Experimental physiologists gave many reasons for the choice of test animals, some practical and others truly comparative. But, despite strong philosophical differences in the approaches they represented, the view that it was best to incorporate as many species as possible into research on physiological processes was widespread in both periodicals. Authors aimed for generality, but they treated it as a conclusion that would or would not follow from the examination of many species. After 1900, an increasing emphasis on standardization, the growth of the experimental method and the growing industrialization of the life sciences led to a decline in the number of species used in research. In this context, the selective breeding of animals for science facilitated a change in assumptions about the relationship between generality and diversity. As animals were increasingly viewed as things that were assumed to be fundamentally similar, scientific generality became an a priori assumption rather than an empirical conclusion.