Fig. 2: Macrophages/monocytes, but not neutrophils and NK/NKT cells, significantly promote malaria transmission.

a The percentage of neutrophils, monocytes, macrophages, DCs, and NK/NKT cells in the midguts of mosquitoes (n = 9) 3 h post-feeding on P. yoelii-infected mice was analyzed using FACS. Twenty midguts were pooled to create one sample, and each has three biological replicates. b Experimental scheme. Mice were treated with or without anti-Ly6G, anti-NK1.1, or CL at 3 days after infection with P. yoelii. Twenty-four hours later, mice were fed to mosquitoes. c, d Mice were treated with or without anti-Ly6G (c), or anti-NK1.1 (d) at 3 days after infection with P. yoelii. Twenty-four hours later, these mice were fed to mosquitoes, and 7 days later, the oocysts number were counted. Both infection intensity and prevalence were calculated and compared. e–j Mice were treated with or without CL at 3 days after infection with P. yoelii (e–g, i) or P. berghei (h, j). Twenty-four hours later, mice were fed to mosquitoes. The relative expression of ookinete-specific genes (n = 9), including SOAP (e) and WARP (f), to the internal control S7 was detected by qPCR in mosquitoes at 12 h post-feeding on CL-treated and control mice. Twenty mosquitoes constitute one sample, and three biological replicates were performed. Both the oocyst infection intensity and prevalence of P. yoelii (g) and P. berghei (h) at 7- or 9-days post-blood meal was compared, respectively. The individual dot represents oocysts number per mosquito, with a line indicating the median. The infection intensity and prevalence of P. yoelii (i) or P. berghei (j) sporozoites in the salivary gland of mosquitoes (n = 15) were counted and compared at 18 days post blood meal. Ten salivary glands constitute one sample, and five biological replicates were performed. k, l At 18 days post-feeding on P. yoelii- or P. berghei-infected mice (treated with or without CL), 5 mosquitoes were allowed to fed on naïve mice, and the onset of blood stage infection were monitored daily for 12 days. The onset of the blood stage of P. yoelii (k) or P. berghei (l) in mice (n = 15) was monitored, after infection by the bite of mosquitoes that fed on P. yoelii- or P. berghei-infected mice (treated with or without CL). m The infection intensity and prevalence of P. falciparum in mosquitoes that fed on P. falciparum-infected RBCs (red blood cells) with or without monocytes isolated from human peripheral blood. The individual dot in panels (c, d, g, h, m) represents oocysts number per mosquito, with a line indicating the median, and the pi chart under each scatter chart indicates the sample size and prevalence in each group. Three independent experiments were performed for each experiment, and the data were pooled. The data in panels (a, e, f, i, j) were presented as mean ± SD. Source data are provided as a Source Data file. Significance was determined by GLMMs test (two-sided) for (c, d, g, h, m); Unpaired t test (two-sided) for (e, f, i, j), Kaplan-Meier analysis was applied for (k, l), and Fisher’s exact test (two-sided) was applied for prevalence analysis. Number between each group represent the P-value, P < 0.05 was consider as statistically significant.