8–12-week-old mice from either wildtype or STAT1 knockout strains were used for organ isolation. Mice were euthanized as per the institutional guidelines. The procedure was performed within an en-closed fume hood. Immediately after euthanasia, the thoracic cavity was opened and a 25G needle at-tached to a canula and syringe containing 7,5% formaldehyde was inserted into the ascending aorta within the left ventricle. The needle was secured in position via a hemostatic forcep. The right atrium was incised using a pair of fine scissors. Prior to perfusion, the abdominal cavity was opened to visu-alize the liver. Perfusion with 7,5% formaldehyde was performed at an average rate of 5ml/min, with a total of 20-25 ml of 7,5% formaldehyde used per animal. Successful perfusion was determined by general stiffness within tissues and pale appearance of the liver. Spleen was dissected carefully with minimal contact and utilizing the fascia associated with splenic capsule to gently isolate the tissue. The splenic tissue was cut (2mm) at either ends and the tissue was incubated in 12% Formalin for further fixation. Wherever possible, minimal pressure and handling of tissue was employed to avoid disrupt-ing the tissue architecture.   After fixation, tissue specimens were processed using a vacuum infiltration processor (Sakura Tissue-Tek VIP 6 AI) equipped with a graded series of alcohol solutions, xylene and molten paraffin. Subse-quently, formalin-fixed paraffin-embedded (FFPE) samples were embedded into paraffin blocks on an embedding workstation (Thermo Scientific HistoStar) before sectioning on a rotary microtome (Ther-mo Scientific HM 355S). Before starting, all surfaces and work areas were wiped with ethanol. After trimming excess paraffin, the FFPE blocks were placed in an ice bath and incubated for 15 minutes, before taking 5 µm tissue sections, which were placed on the respective capture area of the Visium Spatial slide for FFPE (10X Genomics). The Slide was then placed in a drying rack and incubated in an oven at 42°C for 3 hours before being placed in a desiccator overnight at room temperature. Subse-quent steps to obtain sequencing-ready libraries were performed following the manufacturer's instructions. Spatial transcriptomic libraries were generated using the Visium Spatial gene expression reagent kit (10x Genomics) according to the manufacturer's protocol. The sequencing-ready spatial transcriptomics libraries were sequenced by the Biomedical Sequencing Facility at the CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, using the Illumina Novaseq platform and the 75 bp paired-end configuration.