Human IFN-γ ELISA Development Kit

Proliferation of aberrant, dysfunctional lymphatic vessels around solid tumors is a common histologic finding. Studies have shown that abnormalities in lymphatic function result in accumulation of inflammatory cells with an immunosuppressive profile. We tested the hypothesis that dysfunctional lymphatic vessels surrounding solid tumors regulate changes in the tumor microenvironment and tumor-specific immune responses. Using subcutaneously implanted mouse melanoma and breast cancer tumors in a lymphatic endothelial cell-specific diphtheria toxin receptor transgenic mouse, we found that local ablation of lymphatic vessels increased peritumoral edema, as compared with controls. Comparative analysis of the peritumoral fluid demonstrated increases in the number of macrophages, CD4+ inflammatory cells, F4/80(+)/Gr-1(+) (myeloid-derived suppressor cells), CD4(+)/Foxp3(+) (Tregs) immunosuppressive cells, and expression of inflammatory cytokines such as TNFa, IFNg, and IL1b following lymphatic ablation. Tumors grown in lymphatic ablated mice exhibited reduced intratumoral accumulation of cytotoxic T cells and increased tumor PD-L1 expression, causing rapid tumor growth, compared with tumors grown in nonlymphatic-ablated mice. Our study suggests that lymphatic dysfunction plays a role in regulating tumor microenvironments and may be therapeutically targeted in combination with immunotherapy to prevent tumor growth and progression.

Trypanosoma brucei (T.b.) rhodesiense is the cause of the acute form of human African trypanosomiasis (HAT) in eastern and southern African countries. There is some evidence that there is diversity in the disease progression of T.b. rhodesiense in different countries. HAT in Malawi is associated with a chronic haemo-lymphatic stage infection compared to other countries, such as Uganda, where the disease is acute with more marked neurological impairment. This has raised the question of the role of host genetic factors in infection outcomes. A candidate gene association study was conducted in the northern region of Malawi. This was a case-control study involving 202 subjects, 70 cases and 132 controls. All individuals were from one area; born in the area and had been exposed to the risk of infection since birth. Ninety-six markers were genotyped from 17 genes: IL10, IL8, IL4, HLA-G, TNFA, IL6, IFNG, MIF, APOL, HLA-A, IL1B, IL4R, IL12B, IL12R, HP, HPR, and CFH. There was a strong significant association with APOL1 G2 allele (p = 0.0000105, OR = 0.14, CI95 = [0.05-0.41], BONF = 0.00068) indicating that carriers of the G2 allele were protected against T.b. rhodesiense HAT. SNP rs2069845 in IL6 had raw p < 0.05, but did not remain significant after Bonferroni correction. There were no associations found with the other 15 candidate genes. Our finding confirms results from other studies that the G2 variant of APOL1 is associated with protection against T.b. rhodesiense HAT.