BACKGROUND: The genitourinary tract is regarded as part of the mucosal immune system. However, the structural and functional aspects of the human prostate-associated lymphoid tissue (PALT) have never been extensively explored. METHODS: This article describes our investigation of this issue by means of immunohistological, confocal, and ultrastructural examination of the normal human prostate. RESULTS: PALT consists of two main components: (1) intraepithelial leukocytes, namely CD3(+)T cells with prevalent CD8(+) and CD45RA(-)CD45RO(+) phenotype, sometimes CD69(+), followed by CD94(+)NK, CD11c(+)DCs, some expressing CD86, DC-SIGN(+)DCs and a few B lymphocytes; (2) lymphoid aggregates, frequently below the epithelia, arranged in B cell follicles, endowed with a central ICAM-1(+)VCAM-1(+)CD21(+)FDCs network expressing BLC/CXCL13, and parafollicular T cell areas crossed by PNAd(+)HEV-like vessels showing SLC/CCL21 expression. Parafollicular areas were formed of prevalent CD4(+)T lymphocytes, both CD45RA(-) and CD45RO(+), and intermingled with CD11c(+)DCs. Germinal-center-containing follicles are few and their parafollicular areas are scantily infiltrated by Foxp3(+)CD69(-) highly suppressive regulatory T cells. Most lymphoid follicles lack a distinct germinal center and their parafollicular area harbor numerous Foxp3(+)CD69(-) cells. CONCLUSIONS: Comparison with the tonsils shows that PALT displays immunomorphological features required for the onset of cellular and humoral immune responses, while its T regulatory cells appear to function as suppressor-regulators of T and B cell responses.
BACKGROUND: The genitourinary tract is regarded as part of the mucosal immune system. However, the structural and functional aspects of the human prostate-associated lymphoid tissue (PALT) have never been extensively explored. METHODS: This article describes our investigation of this issue by means of immunohistological, confocal, and ultrastructural examination of the normal human prostate. RESULTS: PALT consists of two main components: (1) intraepithelial leukocytes, namely CD3(+)T cells with prevalent CD8(+) and CD45RA(-)CD45RO(+) phenotype, sometimes CD69(+), followed by CD94(+)NK, CD11c(+)DCs, some expressing CD86, DC-SIGN(+)DCs and a few B lymphocytes; (2) lymphoid aggregates, frequently below the epithelia, arranged in B cell follicles, endowed with a central ICAM-1(+)VCAM-1(+)CD21(+)FDCs network expressing BLC/CXCL13, and parafollicular T cell areas crossed by PNAd(+)HEV-like vessels showing SLC/CCL21 expression. Parafollicular areas were formed of prevalent CD4(+)T lymphocytes, both CD45RA(-) and CD45RO(+), and intermingled with CD11c(+)DCs. Germinal-center-containing follicles are few and their parafollicular areas are scantily infiltrated by Foxp3(+)CD69(-) highly suppressive regulatory T cells. Most lymphoid follicles lack a distinct germinal center and their parafollicular area harbor numerous Foxp3(+)CD69(-) cells. CONCLUSIONS: Comparison with the tonsils shows that PALT displays immunomorphological features required for the onset of cellular and humoral immune responses, while its T regulatory cells appear to function as suppressor-regulators of T and B cell responses.
Authors: Mariano Carossino; Alan T Loynachan; Igor F Canisso; R Frank Cook; Juliana R Campos; Bora Nam; Yun Young Go; Edward L Squires; Mats H T Troedsson; Thomas Swerczek; Fabio Del Piero; Ernest Bailey; Peter J Timoney; Udeni B R Balasuriya Journal: J Virol Date: 2017-06-09 Impact factor: 5.103
Authors: Michael A Cerqueira; Karen L Ferrari; Amilcar C de Mattos; Carlos R Monti; Leonardo Oliveira Reis Journal: World J Urol Date: 2019-07-01 Impact factor: 4.226