Kim-Hellmuth Lab

Genetic basis of human immune response variation

The human immune system plays an important role in host protection, autoimmune and inflammatory diseases, cancer, metabolism, and ageing. Given this central role in many human pathologies, it is crucial to understand the variability of immune responses at the population level and how this variability relates to disease susceptibility.

Large genome-wide association studies have implicated hundreds of genetic loci in immune-related genes highlighting the immune system’s role in the biological mechanism underlying genetic risk to numerous diseases. However, for the vast majority of these genetic variants, we have little understanding of their functional effects and their context-specificity. Studying the genetic influence on immune response is further complicated by the complexity of the immune system, which consists of many different cell types that respond to a plethora of signals, interact with each other and induce different effector functions under diverse kinetics.

Our group integrates state-of-the-art genomic and functional genetic approaches to characterize the genetic basis of human immune response variation to advance our understanding of disease-associated variants and answer questions of genome function plasticity that is shaped by gene-by-environment interactions. We focus in particular on molecular quantitative traits (molQTLs) in the context of immune activation and disentangle the cell type and context specificity of functional genetic variants with the ultimate goal to develop a roadmap for complex traits at large and enable the move from genetic discovery to functional interpretation and ultimately clinical impact.

COVID-19 in children and young adults

COVID-19 is an infectious disease caused by the new strain of coronavirus SARS-CoV-2. It was first identified in 2019 in Wuhan, China, and has since spread globally, resulting in the 2019–20 coronavirus pandemic. Common symptoms include fever and cough, however disease symptoms as well as disease course and outcome are highly variable ranging from asymptomatic cases to severe pneumonia and death. While children are likely to have milder symptoms than adults, children of all ages are susceptible to COVID-19 and can suffer from severe disease. Until now it is unknown why children show a different course of disease compared to adults.

Studying the immune response to SARS-CoV-2 in children is therefore critical to rapidly advance our understanding of the pathophysiology of COVID-19 both in children and adults. Children offer a unique possibility to study host-related factors that determine COVID-19 severity in the absence of ageing and comorbidity-related interactions, which are largely determining the disease course in adults.

We have therefore initiated a functional genetics and genomics COVID-19 study to examine the genetic and environmental risk factors of COVID-19 in pediatric and adult patients. Our group integrates deep immune profiling with multi-omics across multiple molecular levels (genome, transcriptome, proteome, metabolome) to enhance our understanding of the human immune response to SARS-CoV-2. Following questions will be addressed:

- Why does SARS-CoV-2 affect children differently compared to adults?

- What are the genetic and immunological risk factors that contribute to this difference?

- Can we use these factors to identify those children who will become severely affected?

As part of the Child Health Alliance Munich (CHANCE) initiative this prospective study is performed at the Dr. von Hauner Children’s Hospital of the Ludwig-Maximilians University (LMU) Munich and the Department of Pediatrics of the Technical University of Munich School of Medicine (TUM). The study is also actively involved in national (Deutsche COVID-19 OMICS Initiative) and international (COVID-19 Host Genetics Initiative) COVID-19 initiatives to join forces in combating this pandemic.

Selected publications:

1. GTEx Consortium#. The GTEx Consortium atlas of genetic regulatory effects across human tissues. Science 369, 1318-1330 (2020). #Lead analyst: Kim-Hellmuth, S.

2. Kim-Hellmuth, S.†*, Aguet, F.*, Oliva, M., Muñoz-Aguirre, M., Kasela, S., Wucher, V., Castel, S. E., Hamel, A. R., Viñuela, A., Roberts, A. L., Mangul, S., Wen, X., Wang, G., Barbeira, A. N., Garrido-Martin, D., Nadel, B., Zou, Y., Bonazzola, R., Quan, J., Brown, A., Martinez-Perez, A., Soria, J. M., GTEx Consortium, Getz, G., Dermitzakis, E., Small, K. S., Stephens, M., Xi, H. S., Im, H. K., Guigó, R., Segre, A. V., Stranger, B. E., Ardlie, K. G. & Lappalainen, T. Cell type specific genetic regulation of gene expression across human tissues. Science 369 (2020). doi: 10.1126/science.aaz8528

3. Oliva, M.*, Muñoz-Aguirre, M.*, Kim-Hellmuth, S.*, Wucher, V., Gewirtz, A., Cotter, D., Parsana, P., Kasela, S., Balliu, B., Viñuela, A., Castel, S. E., Mohammadi, P., Aguet, F., Zou, Y., Khramtsova, E., Skol, A., Garrido-Martin, D., Reverter, F., Brown, A., Evans, P., Gamazon, E., Payne, A., Bonazzola, R., Barbeira, A. N., Hamel, A. R., Martinez-Perez, A., Soria, J. M., GTEx Consortium, Pierce, B., Stephens, M., Eskin, E., Dermitzakis, E., Segre, A. V., Im, H. K., Engelhardt, B., Ardlie, K. G., Montegomery, S., Battle, A., Lappalainen, T., Guigó, R. & Stranger, B. E. The impact of sex on gene expression and its genetic regulation across human tissues. Science 369 (2020). doi: 10.1126/science.aba3066

4. Demanelis, K., Jasmine, F., Chen, L. S., Chernoff, M., Tong, L., Delgado, D., Zhang, C., Shinkle, J., Sabarinathan, M., Lin, H., Ramirez, E., Oliva, M., Kim-Hellmuth, S., Stranger, B. E., Lai, T.-P., Aviv, A., Ardlie, K. G., Aguet, F., Ahsan, H., GTEx Consortium, Doherty, J. A., Kibriya, M. G. & Pierce, B. L. Determinants of telomere length across human tissues. Science 369 (2020). doi: 10.1126/science.aaz6876

5. Brandt, M. K., Kim-Hellmuth, S., Ziosi, M., Gokden, A., Wolman, A., Lam, N., Recinos, Y., Hornung, V. K., Schumacher, J. & Lappalainen, T. An autoimmune disease risk variant has a trans master regulatory effect mediated by IRF1 under immune stimulation. bioRxiv 1–19 (2020). doi:10.1101/2020.02.21.959734

6. Barbeira, A. N.*, Bonazzola, R.*, Gamazon, E. R.*, Liang, Y.*, Park, Y.*, Kim-Hellmuth, S., Wang, G., Jiang, Z., Zhou, D., Hormozdiari, F., Liu, B., Rao, A., Hamel, A. R., Pividori, M. D., Aguet, F., GTEx GWAS working group, Bastarache, L., Jordan, D. M., Verbanck, M., Do, R., GTEx Consortium, Stephens, M., Ardlie, K., McCarthy, M., Montgomery, S. B., Segre, A. V., Brown, C. D., Lappalainen, T., Wen, X. & Im, H. K. Widespread dose-dependent effects of RNA expression and splicing on complex diseases and traits. bioRxiv 6, e1000888–89 (2019).

7. de Goede, O. M., Ferraro, N. M., Nachun, D. C., Rao, A. S., Aguet, F., Barbeira, A. N., Castel, S. E., Kim-Hellmuth, S., Park, Y., Scott, A. J., Strober, B. J., GTEx Consortium, Brown, C. D., Wen, X., Hall, I. M., Battle, A., Lappalainen, T., Im, H. K., Ardlie, K. G., Quertermous, T., Kirkegaard, K. & Montgomery, S. B. Long non-coding RNA gene regulation and trait associations across human tissues. bioRxiv 7, 1860–31 (2019).

8. Kim-Hellmuth, S.†, Bechheim, M., Pütz, B., Mohammadi, P., Nédélec, Y., Giangreco, N., Becker, J., Kaiser, V., Fricker, N., Beier, E., Boor, P., Castel, S. E., Nöthen, M. M., Barreiro, L. B., Pickrell, J. K., Müller-Myhsok, B., Lappalainen, T., Schumacher, J. & Hornung, V. Genetic regulatory effects modified by immune activation contribute to autoimmune disease associations. Nat Commun 8, 266 (2017).

9. Kim-Hellmuth, S. & Lappalainen, T. Concerted Genetic Function in Blood Traits. Cell 167, 1167–1169 (2016).

10. Kehrer, C., Hoischen, A., Menkhaus, R., Schwab, E., Müller, A., Kim, S. et al. Whole exome sequencing and array-based molecular karyotyping as aids to prenatal diagnosis in fetuses with suspected Simpson-Golabi-Behmel syndrome. Prenat Diagn 36, 961–965 (2016).

11. Schäfgen, J., Cremer, K., Becker, J., Kim, S., Aretz, S., Strom, T. M., Wieczorek, D. & Engels, H. De novo nonsense and frameshift variants of TCF20 in individuals with intellectual disability and postnatal overgrowth. European Journal of Human Genetics 24, 1739–1745 (2016).

12. Kim, S., Becker, J., Bechheim, M., Kaiser, V., Noursadeghi, M., Fricker, N., Beier, E., Klaschik, S., Boor, P., Hess, T., Hofmann, A., Holdenrieder, S., Wendland, J. R., Fröhlich, H., Hartmann, G., Nöthen, M. M., Müller-Myhsok, B., Pütz, B., Hornung, V. & Schumacher, J. Characterizing the genetic basis of innate immune response in TLR4-activated human monocytes. Nat Commun 5, 5236 (2014).

13. Kim, S., Kaiser, V., Beier, E., Bechheim, M., Guenthner-Biller, M., Ablasser, A., Berger, M., Endres, S., Hartmann, G. & Hornung, V. Self-priming determines high type I IFN production by plasmacytoid dendritic cells. Eur. J. Immunol. 44, 807–818 (2014).

14. Bauernfeind, F., Ablasser, A., Bartok, E., Kim, S., Schmid-Burgk, J., Cavlar, T. & Hornung, V. Inflammasomes: current understanding and open questions. Cell. Mol. Life Sci. 68, 765–783 (2011).

15. Kim, S., Bauernfeind, F., Ablasser, A., Hartmann, G., Fitzgerald, K. A., Latz, E. & Hornung, V. Listeria monocytogenes is sensed by the NLRP3 and AIM2 inflammasome. Eur. J. Immunol. 40, 1545–1551 (2010).

16. Bauernfeind, F., Ablasser, A., Kim, S., Bartok, E. & Hornung, V. An unexpected role for RNA in the recognition of DNA by the innate immune system. RNA Biology 7, 151–157 (2010).

17. Berger, M., Ablasser, A., Kim, S., Bekeredjian-Ding, I., Giese, T., Endres, S., Hornung, V. & Hartmann, G. TLR8-driven IL-12-dependent reciprocal and synergistic activation of NK cells and monocytes by immunostimulatory RNA. J. Immunother. 32, 262–271 (2009).

18. Ablasser, A., Poeck, H., Anz, D., Berger, M., Schlee, M., Kim, S. et al. Selection of molecular structure and delivery of RNA oligonucleotides to activate TLR7 versus TLR8 and to induce high amounts of IL-12p70 in primary human monocytes. J. Immunol. 182, 6824–6833 (2009).

19. Hornung, V., Ellegast, J., Kim, S., Brzózka, K., Jung, A., Kato, H., Poeck, H., Akira, S., Conzelmann, K.-K., Schlee, M., Endres, S. & Hartmann, G. 5'-Triphosphate RNA is the ligand for RIG-I. Science 314, 994–997 (2006).

†Corresponding author, *Equally contributing author

Complete list of publications

Kim-Hellmuth Lab

Research topics

Dr. med. Sarah Kim-Hellmuth

Dr. Sarah Kim-Hellmuth

Sathya Darmalinggam

Benedict Wendel

Alina Czwienzek

Carola Kaltenhauser

Alumni

Anda Ardeoan

Jöran Sarrazin

12/2020

MD student Alina Czwienzek joins the lab

11/2020

Our COVID-19 case report in a pediatric patient with Down syndrome is out in JPIDS

10/2020

PhD student Sathya Darmalinggam joins the lab

MD student Jöran Sarazzin joins the lab

09/2020

Radio report on the GTEx project with Sarah Kim-Hellmuth

Our GTEx Cell Type Group Paper is out in Science

MD student Ben Wendel joins the lab

The GTEx Main Paper is out in Science

Our GTEx Sex Group Paper is out in Science

08/2020

MD student Anda Ardeoan joins the lab

06/2020

Sarah Kim-Hellmuth presents her work at ESHG 2020

04/2020

MD Student Carola Kaltenhauser joins the lab

News Article covering our Ped-COVID-19 study

Ped-COVID-19 study joins the German COVID-19 OMICS Initiative

03/2020

The Ped-COVID-19 study is launched

Ped-COVID-19 study joins the international COVID-19 Host Genetics Initiative

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