Christian Klotz

Learn More
BACKGROUND Giardia duodenalis is highly endemic in East Africa but its effects on child health, particularly of submicroscopic infections, i.e., those below the threshold of microscopy, and of genetic subgroups (assemblages), are not well understood. We aimed at addressing these questions and at examining epidemiological characteristics of G. duodenalis in(More)
Plasmodium undergoes one round of multiplication in the liver prior to invading erythrocytes and initiating the symptomatic blood phase of the malaria infection. Productive hepatocyte infection by sporozoites leads to the generation of thousands of merozoites capable of erythrocyte invasion. Merozoites are released from infected hepatocytes as merosomes,(More)
Giardia duodenalis is a common flagellated protozoan parasite that infects the small intestine of a wide range of vertebrate hosts. This study aimed to determine whether tracing of G. duodenalis isolates by current genetic typing tools is possible using an exemplary set of samples from infected cattle, buffalo and children from the Ismailia province, Egypt.(More)
Here, we show that Treg limit intestinal pathology during nematode infection and that they control the onset and magnitude of the anti-parasitic Th Th2 response. Using mice expressing the diphtheria toxin receptor under the control of the foxp3 locus, we removed Foxp3(+) Treg during the early phase of infection with Heligmosomoides polygyrus bakeri.(More)
Mast cells (MCs) are potent inflammatory cells that are distributed throughout mucosal barrier tissues and respond rapidly to pathogenic stimuli. During helminth infections, MCs play an important role as late-stage effectors. However, it is currently unknown whether MCs contribute to the early innate events that determine the priming of adaptive immunity.(More)
Possibilities to study the biology of human protozoan parasites and their interaction with the host remain severely limited, either because of non-existent or inappropriate animal models or because parasites cannot even be cultured in vitro due to strict human-host specificity or physiology. Here we discuss the prospects of using induced pluripotent stem(More)
Helminth infections are commonly associated with a Th2 immune response, yet only a few parasite molecules involved in triggering such immune responses have been identified. Here, we describe the Th2-skewing property of calreticulin of Heligmosomoides polygyrus (HpCRT). HpCRT is a secreted protein most abundantly expressed by tissue invasive larvae (L4).(More)
Depletion of arginine is a recognized strategy that pathogens use to evade immune effector mechanisms. Depletion depends on microbial enzymes such as arginases, which are considered virulence factors. The effect is mostly interpreted as being a consequence of successful competition with host enzymes for the substrate. However, both arginases and arginine(More)
To identify new vaccine candidates, Eimeria tenella expressed sequence tags (ESTs) from public databases were analysed for secretory molecules with an especially developed automated in silico strategy termed DNAsignalP. A total of 12,187 ESTs were clustered into 2881 contigs followed by a blastx search, which resulted in a significant number of E. tenella(More)
In order to identify secretory proteins as possible new vaccine candidates, a cDNA-library from E. tenella sporozoites was generated in yeast and was used to select secreted and surface proteins. Herein 191 clones were isolated and analysis of the nucleic acid sequences revealed 162 deduced open reading frames with a prediction for signal peptides. These(More)