Fig 2: Adoptive transfer of GCA+ immune cells aggravated cognitive and memory impairments. A) Experiment design about GCA+ immune cells, GCA− immune cells and PBS controls transferred into Aβ‐injected mice. B–E) In the MWM test, B) the escape latency time, C) representative motion trajectories, D) target quadrant occupancy, E) platform crossing times in GCA+ immune cells, GCA− immune cells and PBS control groups (n = 7). F) Experiment design about novel object recognition test (NORT). G,H) Time with the object was assessed G) and recognition index H) of the NORT (n = 4–6). I) Representative images of IBA1 (red) and nucleus (blue) staining and quantification of IBA1 labeled area in hippocampus and cortex. The boxed regions correspond to Figure S2F. (Scale bar = 50 µm; n = 5). J) Representative images of Neu‐N (green) and nucleus (blue) staining in hippocampus and quantification of Neu‐N labeled area. The boxed regions correspond to Figure S2F (Scale bar = 100 µm; n = 5). K) Representative images of Neu‐N (green) and nucleus (blue) staining in cortex and quantification of Neu‐N labeled area. (Scale bar = 100 µm; n = 5). Data are shown as the mean ± SEM. For panel (B): two‐way ANOVA. For panel (D,E,H–K): one‐way ANOVA. For panel (G): paired, two‐tailed Student's t‐test. * p < 0.05, ** p < 0.01, *** p < 0.001.

Fig 3: Bone marrow‐derived GCA+ immune cells preferentially invaded the brain of AD mouse model in a CCR10‐dependent manner. A) Representative images of PKH26 (red), EGFP (green), CD31 (violet), and nucleus (blue) staining in hippocampus from GCA+ immune cells, GCA− immune cells groups. White arrows indicate cells within the brain parenchyma (Scale bar = 100 µm; n = 4). B) Representative ex vivo fluorescent images from Aβ‐injected mice treated with DiR‐labeled GCA+ immune cells or GCA− immune cells by intravenous injection. C) KEGG enrichment analysis of upregulated genes in GCA+ immune cells compared with GCA− immune cells. D) Heatmap of chemokine receptor genes across GCA+ immune cells and GCA− immune cells. E) Relative cell proportion of CCR10 in GCA+ immune cells and GCA− immune cells (n = 4). (F) Representative immunoblots of CCR10 in GCA+ immune cells and GCA− immune cells. G) Heatmap of Ccl27 and Ccl28 in brain from APP/PS1 mice and control mice (Ccl28, p value < 0.05). H) Relative mRNA levels of Ccl28 in cortex and hippocampus from APP/PS1 mice and control mice. I) Bar chart of GCA+ immune cells and GCA− immune cells migration treated with different concentrations of chemokine, Ccl28 (n = 7). J) Representative immunoblots of CCR10 in GCA+ immune cells treated with treated with AAV‐CMV‐FLEX‐ShCcr10 (AAV‐GCA‐ShCcr10) or AAV‐CMV‐FLEX‐Scramble (AAV‐GCA‐ Scramble) (n = 3). K) Representative images of GFP (green) and nucleus (blue) staining in cortex and hippocampus from Aβ‐injected AAV‐GCA‐ShCcr10 mice or AAV‐GCA‐Scramble mice. (Scale bar = 100 µm; n = 5). Data are shown as the mean ± SEM. For panel (E,H,K): unpaired, two‐tailed Student's t‐test. For panel (I): two‐way ANOVA. * p < 0.05, ** p < 0.01, *** p < 0.001.

Fig 4: GCA‐Neutralizing antibody treatment alleviated AD progression. A) Schematic diagram for treatment and detection time points were indicated. B–E) In the MWM test, B) the escape latency time, C) representative motion trajectories, D) target quadrant occupancy, E) platform crossing times in APP/PS1 mice treated with GCA neutralizing antibody (GCA‐NAb) or IgG control (n = 5). F,G) Time with the object F) and recognition index G) were assessed of the NORT (n = 5). H) Representative images and area percentage of Aβ (green) and nucleus (blue) staining in hippocampus from APP/PS1 mice treated with GCA‐NAb or IgG control. (Scale bar = 100 µm; n = 5). I) Representative images of IBA1 (red), Aβ (green), and nucleus (blue) staining, and bar chart of number of plaque‐associated microglia and the volume percentage of Aβ engulfed by microglia in plaque. (Scale bar = 10 µm; n = 5). J) ELISA of the concentration of soluble A𝛽1‐40 and A𝛽1‐42 in APP/PS1 mice treated with GCA‐NAb or IgG control (n = 4). K) ELISA of the concentration of insoluble A𝛽1‐40 and A𝛽1‐42 in APP/PS1 mice treated with GCA‐NAb or IgG control (n = 4). L) Representative images of Neu‐N (green) and nucleus (blue) staining and quantification of Neu‐N labeled area in hippocampus and cortex. (Scale bar = 200 µm; n = 5). Data are shown as the mean ± SEM. For panel (B): two‐way ANOVA. For panel (D,E,G–L): unpaired, two‐tailed Student's t‐test. For panel (F): paired, two‐tailed Student's t‐test. * p < 0.05, ** p < 0.01.

Fig 5: Genetic ablation of GCA in the hematopoietic cells improved cognitive and memory function A) Schematic diagram for treatment and detection time points were indicated. B–E) In the MWM test, B) the escape latency time, C) representative motion trajectories, D) target quadrant occupancy, E) platform crossing times in Aβ‐injected Gca hematopoietic knockout mice (Gca‐Vav1‐CKO; CKO) and control littermates (Gcaf/f ; Flox) (n = 7). F,G) Time with the object F) and recognition index G) were assessed of the NOR test (n = 7). H) Representative images of IBA1 (red) and nucleus (blue) staining in hippocampus and quantification of IBA1 labeled area from Aβ‐injected CKO mice and Flox mice. (Scale bar = 100 µm; n = 5). I) Representative images of IBA1 (red) and nucleus (blue) staining in cortex and quantification of IBA1 labeled area from Aβ‐injected CKO mice and Flox mice. (Scale bar = 100 µm; n = 5). J) Representative images of Neu‐N (green) and nucleus (blue) staining in hippocampus and quantification of Neu‐N labeled area from Aβ‐injected CKO mice and Flox mice. (Scale bar = 100 µm; n = 5). K) Representative images of Neu‐N (green) and nucleus (blue) staining in cortex and quantification of Neu‐N labeled area from Aβ‐injected CKO mice and Flox mice. (Scale bar = 100 µm; n = 5). Data are shown as the mean ± SEM. For panel (B): two‐way ANOVA. For panel (D,E,G–K): unpaired, two‐tailed Student's t‐test. For panel (F): paired, two‐tailed Student's t‐test. * p < 0.05, ** p < 0.01, *** p < 0.001.