Anti-Granulocytes monoclonal antibody, clone 7E20 [FITC]

Neonatal stroke is as frequent as stroke in the elderly, but many pathophysiological injury aspects are distinct in neonates, induding immune signaling. While myeloid cells can traffic into the brain via multiple routes, the choroid plexus (CP) has been identified as a uniquely educated gate for immune cell traffic during health and disease. To understand the mechanisms of myeloid cell trafficking via the CP and their influence on neonatal stroke, we characterized the phenotypes of CP-infiltrating myeloid cells after transient middle cerebral artery occlusion (tMCAO) in neonatal mice of both sexes in relation to blood-brain barrier permeability, injury, microglial activation, and CX3CR1-CCR2 signaling, focusing on the dynamics early after reperfusion. We demonstrate rapid recruitment of multiple myeloid phenotypes in the CP ipsilateral to the injury, induding inflammatory CD45(+)CD11b(+)Ly6c(high)CD86(+), beneficial CD45(+)CD11b(+)Ly6c(low)CD206(+), and CD45(+)CD11b(+)Ly6c(low)Ly6g(high) cells, but only minor leukocyte infiltration into acutely ischemic-reperfused cortex and negligible vascular albumin leakage. We report that CX3CR1-CCR2-mediated myeloid cell recruitment contributes to stroke injury. Considering the complexity of inflammatory cascades triggered by stroke and a role for TLR2 in injury, we also used direct TLR2 stimulation as an independent injury model. TLR2 agonist rapidly recruited myeloid cells to the CP, increased leukocytosis in the CSF and blood, but infiltration into the cortex remained low over time. While the magnitude and the phenotypes of myeloid cells diverged between tMCAO and TLR2 stimulation, in both models, disruption of CX3CR1-CCR2 signaling attenuated both monocyte and neutrophil trafficking to the CP and cortex.

Toll-like receptors take an essential part in innate immunity in response to invasion of the various harmful pathogens. We aimed to investigate TLR2, 7 and 8 expression in rat testis and epididymis throughout postnatal development. In the prepubertal period, TLR2 and 7 were variably localized to peritubular myoid cells, interstitial cells, blood vessels, epithelial cells, ductal smooth muscle cells in testis and epididymis. In the pubertal period, immunostaining of TLR2 and 7 started to be seen in primary spermatocytes, as well as other cells, in the testis. Narrow cells showed strong intracytoplasmic staining in the epididymis. In the postpubertal period, moderate to strong immunostaining of TLR2 and TLR7 was seen in spermatids at different developmental steps but weak immunoreaction in pachytene spermatocytes. Other cells in testis and epididymis showed variable immunostaining of TLR2 and 7. However, weak to moderate immunoreaction to TLR8 was detected in only interstitial cells in testis. In the mature period, immunostaining of TLR2, 7 and 8 tended to increase in different types of cells in testis and epididymis. Our findings suggest that expression of TLR2, 7 and 8 changed dynamically during postnatal development and increased towards mature period. We consider that TLR2, 7 and 8 might be associated with the regulation of spermatogenesis and the maintenance of innate immunity of testis and epididymis during postnatal development.