Phage Display Identification of CD100 in Human Atherosclerotic Plaque Macrophages and Foam Cells

Abstract

Atherosclerosis is a complex disease in which vessels develop plaques comprising dysfunctional endothelium, monocyte derived lipid laden foam cells and activated lymphocytes. Considering that humans and animal models of the disease develop quite distinct plaques, we used human plaques to search for proteins that could be used as markers of human atheromas. Phage display peptide libraries were probed to fresh human carotid plaques, and a bound phage homologous to plexin B1, a high affinity receptor for CD100, was identified. CD100 is a member of the semaphorin family expressed by most hematopoietic cells and particularly by activated T cells. CD100 expression was analyzed in human plaques and normal samples. CD100 mRNA and protein were analyzed in cultured monocytes, macrophages and foam cells. The effects of CD100 in oxLDL-induced foam cell formation and in CD36 mRNA abundance were evaluated. Human atherosclerotic plaques showed strong labeling of CD100/SEMA4D. CD100 expression was further demonstrated in peripheral blood monocytes and in in vitro differentiated macrophages and foam cells, with diminished CD100 transcript along the differentiation of these cells. Incubation of macrophages with CD100 led to a reduction in oxLDL-induced foam cell formation probably through a decrease of CD36 expression, suggesting for the first time an atheroprotective role for CD100 in the human disease. Given its differential expression in the numerous foam cells and macrophages of the plaques and its capacity to decrease oxLDL engulfment by macrophages we propose that CD100 may have a role in atherosclerotic plaque development, and may possibly be employed in targeted treatments of these atheromas.

Semaphorins in cardiovascular medicine

“…Human atherosclerotic plaques express high levels of SEMA4D as well as foam cells. Furthermore, SEMA4D inhibits the differentiation of macrophages into foam cells, which is otherwise induced by oxidized lipoproteins by down-modulating the expression of CD36, which has a relevant role in lipoprotein trafficking and atherogenesis [71].…”

Caracterização funcional de CD100/Sema4D na infecção de macrófagos por <i>Leishmania</i> (<i>Leishmania</i>) <i>amazonensis</i>.

“…Essa proteína é encontrada como um dímero ligado à membrana no tamanho de 150 kDa (por subunidade) ou na forma solúvel no tamanho de 120 kDa (sCD100), obtida por clivagem (BASILE et al, 2007;ELHABAZI et al, 2003;ZHU et al, 2007). Essa clivagem é feita em plaquetas por uma metaloprotease ADAM17 (ZHU, 2007 (MOREAUFAUVARQUE et al, 2003), em crescimento e angiogênese tumorais (BASILE et al, 2006;CH'NG;KUMANOGOH, 2010;GABROVSKA et al, 2011;KATO et al, 2011;SIERRA et al, 2008;SOONG et al, 2011;YANG et al, 2011), em osteogênese (NEGISHI-KOGA et al, 2011) e em aterosclerose (LUQUE et al, 2013;LUQUE et al, 2015), e ainda foi mostrado que CD100 também é expressa em plaquetas, participando ora da formação de trombos, ora da recuperação da monocamada endotelial (ZHU et al, 2007). …”

“…Estudos de nosso grupo mostraram que placas ateroscleróticas humanas possuem macrófagos que expressam CD100, sendo essa proteína responsável pela diminuição da internalização de LDL oxidado por inibir seu receptor CD36 (LUQUE et al, 2013).…”

“…Interessantemente, vimos que apenas parte dos macrófagos de baço expressam CD100, sugerindo que essa molécula possa estar relacionada com subtipos específicos de macrófagos (LUQUE et al, 2013). Em um segundo trabalho, mostramos que CD100 e as plexinas, especialmente plexina B2, contribuem para a ligação de monócitos humanos a células endoteliais in vitro, e que essas duas células expressam CD100 na membrana, apontando para a proteína como um dos participantes na interação célula endotelial-monócito, um passo importante na aterogênese e formação de trombos (LUQUE et al, 2015).…”

Efeito do laser de baixa intensidade e da proteína purificada do látex natural (Hevea brasiliensis) sobre a lesão por esmagamento do nervo isquiático de ratos wistar: estudo morfológico, imunohistoquímico e ultraestrutural.

“…As células espumosas são macrófagos ativos com acúmulos de lipídeos em seu citoplasma (BOVEN et al, 2006;LUQUE et al, 2013;SENGUPTA et al, 2013).…”