*2.4. Sampling of Biological Material and Processing of Samples*

At the end of experiments, the animals were anesthetized with ketamine/acepromazine/ xylazine cocktail (ketamine 80 mg/kg, Richterpharma ag, Wells, Austria; acepromazine 6 mg/kg, Vetoquinol SA, Lure, France; xylazine 1 mg/kg, Bioveta SA, Czech Republic) for blood, spleen and skin sample collection. Peripheral blood was collected by intra-cardiac puncture in K2-EDTA coated tubes (SARSTEDT AG & CO. KG, Nümbrecht, Germany). Spleens were weighed (Balance AEP-1500A, Adam Equipment Co., Ltd., Kingston, UK) for splenomegaly evaluation and processed in order to isolate the spleen cells. The spleens were collected in 5% FBS RPMI 1640 media (Biochrom AG GmbH, Berlin, Germany), passed through a 70 µm cell strainer (BD Falcon -BD Biosciences, San Jose, CA, USA), cells centrifuged for 5 min at 350× *g* (20 ◦C) and resuspended in RBC Lysis Buffer (BioLegend, San Diego, CA, USA). After 5 min on ice, 10 mL Cell Staining Buffer (BioLegend, San Diego, CA, USA) was added in order to stop the lysis and centrifuged for 5 min at 350× *g* (20 ◦C). The pellet was resuspended twice in Cell Staining Buffer, for a final concentration of 1 × 10<sup>6</sup> cells/mL. Skin samples were collected and processed (fixed in 10% buffered formalin, embedded in paraffin, sectioned in 5 µm sections) for hematoxylin and eosin (H&E) staining, prior to histopathological evaluation (Olympus BX43 with CellSens Dimension Program, Tokyo, Japan).
