Immunohistochemical characterization of leucocyte subpopulations in endometriotic lesions

Abstract

Leucocyte subpopulations localized in endometriotic lesions were analysed using the avidin-biotin immunoperoxidase technique on 15 biopsies obtained by CO2 laser excision. Qualitative assessment of the leucocyte subpopulations was performed with a panel of antihuman monoclonal antibodies for leucocytes (anti-Hle-1), T-lymphocytes (anti-leu-4), T helper/inducer (anti-leu-3a), T suppressor/cytotoxic (anti-leu-2a), B cells (anti-leu-12), HLA-DR (anti-HLA-DR), macrophages (anti-leu-M3) and natural killer cells (anti-leu-7, anti-leu-11; anti-leu-19). Leucocyte common antigen (anti-Hle-1)-positive cells were present in all lesions and were the most frequent stromal leucocytes. Of these, the T lymphocytes are the most frequent subpopulation together with the macrophages. The CD4/CD8 ratio was 0.78. No anti-leu-7 and/or anti-leu-11-positive cells were found although a substantial amount of anti-leu-19-positive cells were found in each lesion. There were very few B cells present in the ectopic endometrial lesions. In conclusion, an important amount of cytotoxic lymphocytes (anti-leu-2a -and anti-leu-19-positive cells) and macrophages (anti-leu-M3) were found in the endometriotic lesions. The possible importance of these intraendometriotic leucocytes for the pathophysiology of endometriosis will be discussed.

Interleukin-4 Stimulates Proliferation of Endometriotic Stromal Cells

“…It has been shown that multiple immune cells, eg, macrophages, T lymphocyte, NK cells, mast cells, eosin- 14,31,32 The immune cells in endometriotic tissues are suggested to be involved in the development of endometriosis by inducing various events such as inflammation, proliferation, invasion, angiogenesis, and fibrosis. 4 In these events, cytokines from the immune cells play important roles, acting directly on ESCs or modulating other immune cell functions.…”

Phenotypic and functional studies of leukocytes in human endometrium and endometriosis

“…Although it has been suggested that NK cells play an important role in the aetiology of endometriosis, several studies have shown that CD56+ CD16+ 'classical' NK cells are only present in negligible numbers in eutopic and ectopic endometrium Klentzeris et al, 1992;Oosterlynck et al, 1993;Fernández-Shaw et al, 1995;Jones et al, 1996;Lachapelle et al, 1996). In contrast, the unusual CD56+ CD16-eGLs are present in large numbers in eutopic endometrium, but their presence in ectopic endometrium has received scant attention.…”

Pathogenesis of Endometriosis

“…Studies of ectopic endometrium have revealed increased concentrations of stromal leukocytes compared to eutopic endometrium. This is accounted for by increases in macrophages, T helperinducer (CD4), and T cytolytic-suppressor (CD8) cells [87][88][89][90]. In addition, we have demonstrated an increased proportion of activated T cells [89] and that the T cells and macrophages express greater amounts of interferon-Á in endometriotic implants compared to eutopic endometrium [91].…”

“…In addition, we have demonstrated an increased proportion of activated T cells [89] and that the T cells and macrophages express greater amounts of interferon-Á in endometriotic implants compared to eutopic endometrium [91]. Furthermore, the number of NK cells is decreased in ectopic endometrium [87][88][89]. It is hypothesized that resident leukocytes in endometriosis, by responding to and by producing cytokines, may help account for differential growth and persistence of implants.…”