Figure 3
Gametocytes are enriched in the bone marrow and the spleen.
(a) Histological sections of sternum bone marrow, spleen, liver and lung were stained with antibodies directed against Pfg27 and HSP70 to detect gametocytes and all parasites, respectively. n = total number of HSP70- and Pfg27-positive parasites observed in 30 fields at 630X magnification for each tissue sample for 5 mice (a total of 1, 200 fields was analyzed). Bars represent 10 μm. (b) Proportion of Pfg27-positive gametocytes in the HSP70-positive parasite population in bone marrow (BM), spleen (SP), lung and liver. Results represent the average ratio of Pfg27-positive cells in Pfg27-stained sections to HSP70-positive cells in HSP70-stained sections observed in 30 fields. Stars represent significant differences in proportion (**P < 0.01, *P < 0.05). ns: not significant. (c) Quantitative analysis by real time RT-qPCR of gametocytes distribution in peripheral blood (PB), femur bone marrow (BM), spleen (SP), lung and liver. Relative copy numbers (RCN) of the gametocyte marker Pfs48/45 were calculated as the ratio between copy numbers of Pfs48/45 transcripts and the geometric mean of the ring upregulated gene sbp1 and the trophozoite upregulated gene hprt transcripts. Results represent the average quantification for 8 mice from two independent infection experiments. (d) Histological sections of bone marrow (sternum) were stained with antibodies directed against laminin to detect basement membrane of microvasculature (V). Hemozoin malaria pigment allows detection of parasites in intra- (green arrow) or extra- (yellow arrow) vascular space. Bars represent 10 μm. (e) Proportion of intra- and extra-vascular parasites observed in a population of 200 parasites on laminin-stained histological sections from three mice.
