title: Preventive Anti-CD2 Treatment does not Impair Parasite Control in a Murine Toxoplasmosis Model.
abstract: Targeting human CD2 with the monoclonal antibody (mAb) CB.219 reduces intestinal inflammation in a colitis model where T cells carry human CD2. Here, we asked whether this mAb has adverse effects on infection control. Mice expressing human CD2 on T cells (huCD2tg) were orally infected with Toxoplasma (T.) gondii and treated with the human CD2-specific mAb CB.219 in a preventive setting. The intestinal T. gondii loads in CB.219 treated mice did not differ from the control group. Histologically, huCD2tg mice showed moderate ileal inflammation that did not change with CB.219 treatment. In the ileum, CB.219 treatment reduced the protein levels of interferon-γ, transforming growth factor β and interleukin-6, whereas interleukin-18 mRNA was slightly increased. The infiltration of neutrophils, macrophages, and T cells into the ileum was unaffected by CB.219 treatment. However, CB.219 treatment decreased the numbers of forkhead box P3(+) regulatory T cells (Treg) in ileum and liver of huCD2tg mice. This was confirmed in vitro using human peripheral blood mononuclear cells. Taken together, targeting CD2(+) T cells by the human CD2 mAb CB.219 does not prevent beneficial immune reactions necessary for pathogen control. Further experiments will address gut specificity, underlying mechanisms, and general applicability of CB.219 treatment.
authors.affiliation: Medical Department (Gastroenterology, Infectious Diseases, Rheumatology), Campus Benjamin Franklin, Chari té - Universitätsmedizin Berlin , Berlin, Germany ; Research Center ImmunoSciences, Charité - Universitätsmedizin Berlin , Berlin, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Erben
authors.affiliation: Immatics Biotechnologies GmbH , Tübingen, Germany.
authors.forename: N N
authors.initials: NN
authors.lastname: Pawlowski
authors.affiliation: Institute for Microbiology and Hygiene, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin , Berlin, Germany.
authors.forename: M M
authors.initials: MM
authors.lastname: Heimesaat
authors.affiliation: Pathotres Joint Practice for Pathology , Berlin, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Loddenkemper
authors.affiliation: Cold Spring Harbor Laboratory , Cold Spring Harbor, New York, USA.
authors.forename: K
authors.initials: K
authors.lastname: Doerfel
authors.affiliation: Medical Department (Gastroenterology, Infectious Diseases, Rheumatology), Campus Benjamin Franklin, Chari té - Universitätsmedizin Berlin , Berlin, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Spieckermann
authors.affiliation: Medical Department (Gastroenterology, Infectious Diseases, Rheumatology), Campus Benjamin Franklin, Chari té - Universitätsmedizin Berlin , Berlin, Germany ; Research Center ImmunoSciences, Charité - Universitätsmedizin Berlin , Berlin, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Siegmund
authors.affiliation: Medical Department (Gastroenterology, Infectious Diseases, Rheumatology), Campus Benjamin Franklin, Chari té - Universitätsmedizin Berlin , Berlin, Germany ; Research Center ImmunoSciences, Charité - Universitätsmedizin Berlin , Berlin, Germany.
authors.forename: A A
authors.initials: AA
authors.lastname: Kühl
keywords: CD2; experimental ileitis; infection model; inflammatory bowel disease