In Vitro Characterization of Human Intestinal Intraepithelial Lymphocytes

Isolation and characterization of lymphocytes from bovine intestinal epithelium and lamina propria

“…Maximal proliferation of bovine IEL occurred at a Con A concentration of 1-5 ]~g/ml, or 2-10-fold less than the optimal concentration reported for porcine IEL (Wilson et al, 1986a), although this apparent difference in sensitivity may be due to different culture conditions. Bovine LP lymphocytes, like those from the other species documented in the literature (Arnaud-Battandier and Nelson, 1982;Greenwood et al, 1983;Nauss et al, 1984), proliferated when stimulated with Con A.…”

“…The present experiments demonstrate that rhIL-2 can enhance the proliferative responses of lymphocytes from the epithelium and LP of the bovine gut. However, the ability of gut lymphocytes to produce IL-2 in vitro, as has been shown for human (Greenwood et al, 1983), murine (Arnaud-Battandier and Nelson, 1982;Nauss et al, 1984) and porcine (Wilson et al, 1986b) LP has yet to be determined.…”

Human intraepithelial lymphocytes

“…Furthermore, initial studies using human T lymphocyte-specific monoclonal antibodies showed that 95 % or more IEL carried the CD3 marker which is associated with the T cell receptor (TcR) on all T cells [102,103]. This finding has since been amply confirmed by many other workers [9,13,36,45,46,65,107]. The lack, until recently, of equivalent CD3-specific reagents has prevented similar studies in other species, but it has been reported that 85 %-90 % of mouse IEL are CD3 ÷ [35].…”

“…Nevertheless, there now seems to be general agreement that a substantial proportion of human IEL, even from normal intestine, are larger than lymphocytes from other tissues. Around three-quarters are described as medium-sized and have some features consistent with activation, including prominent lysosomes and a large amount of nuclear heterochromatin [9,11,36,66,92,113]. True lymphoblasts are rare, but the possibility that many IEL are activated is supported by their "amoeboid" appearance in situ [113,118] and by their unusually high locomotor activity in vitro (see below).…”

“…2). In man, around 25 % of IEL contain granules, but this may often be higher and can approach 80%, particularly in rodent studies [9,11,15,18,36,38,76,112]. The nature of these granules has not been determined with certainty and has provoked considerable speculation over the origin and lineage of IEL.…”