Tuberculosis in Newborns: The Lessons of the “Lübeck Disaster” (1929–1933)

<div><p>In an accident later known as the Lübeck disaster, 251 neonates were orally given three doses of the new Bacille Calmette–Guérin (BCG) antituberculosis (TB) vaccine contaminated with <i>Mycobacterium tuberculosis</i>. A total of 173 infants developed clinical or radiological signs of TB but survived the infection, while 72 died from TB. While some blamed the accident on BCG itself by postulating reversion to full virulence, such a possibility was conclusively disproven. Rather, by combining clinical, microbiological, and epidemiological data, the chief public health investigator Dr. A. Moegling concluded that the BCG vaccine had been contaminated with variable amounts of fully virulent <i>M</i>. <i>tuberculosis</i>. Here, we summarize the conclusions drawn by Moegling and point out three lessons that can be learned. First, while mortality was high (approximately 29%), the majority of neonates inoculated with <i>M</i>. <i>tuberculosis</i> eventually overcame TB disease. This shows the high constitutional resistance of humans to the bacillus. Second, four semiquantitative levels of contamination were deduced by Moegling from the available data. While at low levels of <i>M</i>. <i>tuberculosis</i> there was a large spread of clinical phenotypes reflecting a good degree of innate resistance to TB, at the highest dose, the majority of neonates were highly susceptible to TB. This shows the dominating role of dose for innate resistance to TB. Third, two infants inoculated with the lowest dose nevertheless died of TB, and their median time from inoculation to death was substantially shorter than for those who died after inoculation with higher doses. This suggests that infants who developed disease after low dose inoculation are those who are most susceptible to the disease. We discuss some implications of these lessons for current study of genetic susceptibility to TB.</p></div

Summary of clinical status of TB in newborns during three-year follow-up.

<p>The figure uses data extracted from Tables 8 and 9 in Moegling’s report. All but six children who survived until September 1933 achieved complete clinical remission. Six of the seven clinical categories of TB are presented (excluding “no signs of disease and a negative TST”). Severe illness in this figure combines both (a) severe illness with worst prognosis and (b) severe illness with questionable, eventually unfavourable, prognosis.</p

Evidence for cis-eQTL in stimulated <i>versus</i> non-stimulated cells.

<p>For each gene, we plotted the SNP with the lowest <i>P</i> value obtained under an additive model in one condition (stimulated or non-stimulated) against the <i>P</i> value obtained under the alternative condition. Red and grey dashed lines correspond to the 0.01 and to the 0.5 FDR to classify response eQTL (reQTL). Green dots are general cis-eQTL (found in both conditions). Blue dots are reQTL specific to cells stimulated with <i>M</i>. <i>leprae</i> sonicate while pink dots are reQTL specific to untreated cells. For this figure, reQTL are variants that exhibit a significant <i>P</i> value for genotype-phenotype association in one condition at an FDR of 0.01 and not in the other condition at an FDR of 0.5 (without taking the entire 200-kb tested regions per gene into account). The orange cloud corresponds to all the variants detected as being cis-eQTL at an FDR of 0.01.</p

Evidence for cis-eQTL in stimulated <i>versus</i> non-stimulated cells.

<p>For each gene, we plotted the SNP with the lowest <i>P</i> value obtained under an additive model in one condition (stimulated or non-stimulated) against the <i>P</i> value obtained under the alternative condition. Red and grey dashed lines correspond to the 0.01 and to the 0.5 FDR to classify response eQTL (reQTL). Green dots are general cis-eQTL (found in both conditions). Blue dots are reQTL specific to cells stimulated with <i>M</i>. <i>leprae</i> sonicate while pink dots are reQTL specific to untreated cells. For this figure, reQTL are variants that exhibit a significant <i>P</i> value for genotype-phenotype association in one condition at an FDR of 0.01 and not in the other condition at an FDR of 0.5 (without taking the entire 200-kb tested regions per gene into account). The orange cloud corresponds to all the variants detected as being cis-eQTL at an FDR of 0.01.</p

Family based sample and study design.

<p>Two sets of families were employed: those with T1R-affected offspring and those with leprosy but T1R-free offspring. The T1R-affected subset comprised 229 offspring belonging to 221 families while the T1R-free subset comprised 229 offspring in 209 families. Offspring were matched by clinical leprosy subtype in the two family sets. In a first analysis stage, the transmission disequilibrium test (TDT) was used to estimate significance of association of <i>LRRK2</i> variants with disease in each subset. In a second stage, a formal heterogeneity test was performed to identify <i>LRRK2</i> variants preferentially associated with T1R.</p

LRRK2 variants preferentially associated with T1R.

<p>LRRK2 variants preferentially associated with T1R.</p

Host versus pathogen control of <i>LRRK2</i> expression levels.

<p><i>LRRK2</i> expression levels for 53 unrelated subjects are indicated on the y-axis and stratified according to rs2404580 genotypes on the x-axis. The left panel represents baseline expression while the right panel indicates gene expression levels following stimulation with <i>M</i>. <i>leprae</i> antigen.</p

Specific Dysregulation of IFNγ Production by Natural Killer Cells Confers Susceptibility to Viral Infection

<div><p>Natural Killer (NK) cells contribute to the control of viral infection by directly killing target cells and mediating cytokine release. In C57BL/6 mice, the Ly49H activating NK cell receptor plays a key role in early resistance to mouse cytomegalovirus (MCMV) infection through specific recognition of the MCMV-encoded MHC class I-like molecule m157 expressed on infected cells. Here we show that transgenic expression of Ly49H failed to provide protection against MCMV infection in the naturally susceptible A/J mouse strain. Characterization of Ly49H⁺ NK cells from <i>Ly49h</i>-A transgenic animals showed that they were able to mount a robust cytotoxic response and proliferate to high numbers during the course of infection. However, compared to NK cells from C57BL/6 mice, we observed an intrinsic defect in their ability to produce IFNγ when challenged by either m157-expressing target cells, exogenous cytokines or chemical stimulants. This effect was limited to NK cells as T cells from C57BL/6 and <i>Ly49h</i>-A mice produced comparable cytokine levels. Using a panel of recombinant congenic strains derived from A/J and C57BL/6 progenitors, we mapped the genetic basis of defective IFNγ production to a single 6.6 Mb genetic interval overlapping the <i>Ifng</i> gene on chromosome 10. Inspection of the genetic interval failed to reveal molecular differences between A/J and several mouse strains showing normal IFNγ production. The chromosome 10 locus is independent of MAPK signalling or decreased mRNA stability and linked to MCMV susceptibility. This study highlights the existence of a previously uncovered NK cell-specific <i>cis</i>-regulatory mechanism of <i>Ifnγ</i> transcript expression potentially relevant to NK cell function in health and disease.</p></div

Multivariate analysis of <i>LRRK2</i> variants with T1R

<p>Multivariate analysis of <i>LRRK2</i> variants with T1R</p

Proposed mechanism for LRRK2 in T1R.

<p>The LRRK2 M2397T amino acid substitution affects protein turnover. The methionine variant of LRRK2 displays a half-life of approximately 8 hours while the half-life of the threonine variant is 18 hours [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004412#pntd.0004412.ref034" target="_blank">34</a>]. LRRK2 arrests the NFAT transcription factor in the cytoplasm through a complex mechanism mediated by Ca²⁺ [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004412#pntd.0004412.ref036" target="_blank">36</a>]. This prevents NFAT to migrate to the nucleus and trigger the expression of pro-inflammatory cytokines [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0004412#pntd.0004412.ref035" target="_blank">35</a>]. The M2397 allele is in tight linkage disequilibrium with alleles of SNPs that promote an increase in <i>LRRK2</i> expression creating a compensatory mechanism to counterbalance the shorter LRRK2-M2397 half-life. This compensatory mechanism is abrogated in the presence of <i>M</i>. <i>leprae</i> antigen. Hence, the effect of the M2397T amino acid substitution is most pronounced in the presence of <i>M</i>. <i>leprae</i> antigen.</p