Projects Experimental Infection Research

Immunological sensing of human cytomegalovirus (HCMV)

Currently 60-100% of the world´s population is latently infected with HCMV. This represents a major health problem as the infection can lead to severe morbidity and mortality in immunocompromised individuals. However, in immunocompetent persons HCMV infection is mostly unnoticed as the virus developed sophisticated means to avoid immune responses and thus can persist in a latent state. In light of these multilayered evasion strategies we aim to better understand how HCMV is sensed by the immune system and how antiviral protection mechanisms are induced. Therefore, we focus especially on sensing of CMV by myeloid cells in the human and murine model and on the induction of type I interferons which can exhibit pro- and anti-viral effects on HCMV infection. By applying single cell analysis approaches we aim to elucidate the delicate balance between the host response and the evasion strategies deployed by HCMV.

Publications

Regulation of acute hepatitis

The pathogenesis of virus-induced hepatitis is not well understood and immunological therapies aiming at re-adjustment of immunological processes are not available. Therefore, we established mouse models of acute viral hepatitis that are currently being studied. At present we study how liver resident Kupffer cells and infiltrating peripheral myeloid cells react upon hepatic infection. The objective is to better understand local immune mechanisms within the liver that modulate anti-viral defense and inflammation.

Publications

Virus control within the CNS

Even though virus infection of the central nervous system (CNS) is a relatively rare event, it causes high morbidity and mortality. Currently, efficacious therapies are very limited due to an incomplete understanding of molecular processes underlying anti-viral control and pathogenesis within the CNS. Upon intranasal instillation, VSV infects olfactory sensory neurons within the nasal epithelium and then moves within the axons into peripheral areas of the olfactory bulb. There, type I interferon receptor expression of CNS resident cells, including astrocytes, oligodendrocytes and neurons, is essential to protect against acute viral encephalitis. Within the olfactory bulb primarily astrocytes produce the protective type I interferon. Currently we are aiming at understanding how virus is sensed within the CNS and how type I interferon responses trigger protective immunity. In addition to VSV these studies are carried out also with HSV.

Publications

Towards the molecular mechanism of HBV vaccination non-responsiveness

The intramuscularly applied HBV vaccine leads to the activation of immune cells. As a consequence, B cells release protective antibodies, which can neutralize HBV.

Since 1986, genetically engineered second generation HBV vaccines are on the market which consist the HBV surface antigen (HBsAg). The vaccines are produced in yeast and formulated with alum as adjuvant. They are considered the first true anti-cancer vaccine. Even though second generation HBV vaccines are considered to be amongst the safest and most effective vaccines ever made, approximately 5% of vaccinated individuals do not respond to vaccination. Therefore, we aim at identifying immunological and genetic mechanisms of non-responsiveness to HBV-vaccination. Based on this information we will then search for new strategies to overcome the HBV vaccination non-responsiveness. This project is carried out by an interdisciplinary group of clinicians and immunological experts at different centers of the Helmholtz Association, the German Cancer Research Centre (DKFZ), the Helmholtz-Center Munich, and the HZI, and clinical units of MHH and the Technical University Munich (TUM).

Development of a topical anti-inflammatory mAb therapy

For the superagonistic antibody TGN1412 we found that interaction with Fcγ receptor expressing cells is needed in order to exhibit its function, i.e., T cell-receptor independent stimulation of T cells . Similarly, also the CD4-specific monoclonal antibody BT061 needs interaction with Fcγ receptor expressing cells in order to induce CD4 down-modulation on T cells . Specifically, our data showed that interaction of BT061 decorated T cells with inflammatory cells expressing the high affinity Fcγ receptor CD64 are needed. Therefore, now we test whether upon direct application into inflamed joints BT061 can modulate inflammation.

Publications

Cell-selective delivery of active compounds

Glycan-decorated liposomes enhance targeting of APCs such as macrophages and dendritic cells, while providing a preferential delivery of their payload to endo/lysosomal compartments.

Upon systemic administration of new drugs entirely unexpected adverse effects can be induced in addition to the anticipated effects, which make the development of new compounds very difficult and time consuming. Therefore, we aim at the development of cell-selective delivery of approved drugs with established functions and known adverse effects. Currently we test different antibiotics encapsulated in glycan-functionalized liposomes (TargoSpheres®) in in vitro and in vivo settings. The hope is that this way antibiotic resistance of intracellular pathogens can be overcome and adverse effects can be avoided.

Publications

Immunological sensing of human cytomegalovirus (HCMV)

Hirche C, Frenz T, Haas SF, Doring M, Borst K, Tegtmeyer PK, Brizic I, Jordan S, Keyser K, Chhatbar C, Pronk E, Lin S, Messerle M, Jonjic S, Falk CS, Trumpp A, Essers MAG, Kalinke U (2017) Systemic Virus Infections Differentially Modulate Cell Cycle State and Functionality of Long-Term Hematopoietic Stem Cells In Vivo. Cell Rep 19(11): 2345-2356.

Doring M, Lessin I, Frenz T, Spanier J, Kessler A, Tegtmeyer P, Dag F, Thiel N, Trilling M, Lienenklaus S, Weiss S, Scheu S, Messerle M, Cicin-Sain L, Hengel H, Kalinke U (2014) M27 expressed by cytomegalovirus counteracts effective type I interferon induction of myeloid cells but not of plasmacytoid dendritic cells. J Virol 88(23): 13638-13650.

Paijo J, Doring M, Spanier J, Grabski E, Nooruzzaman M, Schmidt T, Witte G, Messerle M, Hornung V, Kaever V, Kalinke U (2016) cGAS Senses Human Cytomegalovirus and Induces Type I Interferon Responses in Human Monocyte-Derived Cells. PLoS Pathog 12(4): e1005546.

Regulation of acute hepatitis

Grabski E, Wappler I, Pfaender S, Steinmann E, Haid S, Dzionek A, Pietschmann T, Kalinke U (2015) Efficient virus assembly, but not infectivity, determines the magnitude of hepatitis C virus-induced interferon alpha responses of plasmacytoid dendritic cells. J Virol 89(6): 3200-3208.

Pfaender S, Grabski E, Detje CN, Riebesehl N, Lienenklaus S, Steinmann E, Kalinke U, Pietschmann T (2016) Hepatitis C Virus Stimulates Murine CD8alpha-Like Dendritic Cells to Produce Type I Interferon in a TRIF-Dependent Manner. PLoS Pathog 12(7): e1005736.

Virus control within the CNS

Detje CN, Meyer T, Schmidt H, Kreuz D, Rose JK, Bechmann I, Prinz M, Kalinke U (2009) Local type I IFN receptor signaling protects against virus spread within the central nervous system. J Immunol 182(4): 2297-2304.

Detje CN, Lienenklaus S, Chhatbar C, Spanier J, Prajeeth CK, Soldner C, Tovey MG, Schluter D, Weiss S, Stangel M, Kalinke U (2015) Upon intranasal vesicular stomatitis virus infection, astrocytes in the olfactory bulb are important interferon Beta producers that protect from lethal encephalitis. J Virol 89(5): 2731-2738.

Development of a topical anti-inflammatory mAb therapy

Bartholomaeus P, Semmler LY, Bukur T, Boisguerin V, Romer PS, Tabares P, Chuvpilo S, Tyrsin DY, Matskevich A, Hengel H, Castle J, Hunig T, Kalinke U (2014) Cell contact-dependent priming and Fc interaction with CD32+ immune cells contribute to the TGN1412-triggered cytokine response. J Immunol 192(5): 2091-2098.

Vogel S, Grabski E, Buschjager D, Klawonn F, Doring M, Wang J, Fletcher E, Bechmann I, Witte T, Durisin M, Schraven B, Mangsbo SM, Schonfeld K, Czeloth N, Kalinke U (2015) Antibody induced CD4 down-modulation of T cells is site-specifically mediated by CD64(+) cells. Sci Rep 5: 18308.

Cell-selective delivery of active compounds

Frenz T, Grabski E, Duran V, Hozsa C, Stepczynska A, Furch M, Gieseler RK, Kalinke U (2015) Antigen presenting cell-selective drug delivery by glycan-decorated nanocarriers. Eur J Pharm Biopharm 95(Pt A): 13-17.