Accumulation of mucosal T lymphocytes around epithelial cells after in vitro infection with Cryptosporidium parvum

J Parasitol. 1999 Aug;85(4):765-8.


We had previously shown that ileal intraepithelial lymphocytes isolated from calves with cryptosporidiosis include significantly increased numbers of CD8+ T lymphocytes and activated CD4+ cells. These increases could result from redistribution of resident mucosal lymphocytes or from homing of peripheral T cells to ileal mucosa. To determine whether resident mucosal lymphocytes can redistribute to Cryptosporidium parvum-infected epithelium, oocysts were inoculated in vitro onto ileum explants taken from 1-2-wk-old noninfected calves. After 24 hr of incubation, the explants were collected and frozen in liquid nitrogen. Immunohistochemical analysis of T-lymphocyte subpopulations was performed on sections, and labeled lymphocytes adjacent to villous epithelial cells were counted. Compared with uninoculated explants, there was a statistically significant increase in the number of CD8+ T lymphocytes per 100 epithelial cells in oocyst-inoculated tissue. In addition, there were increased numbers of CD4+ T cells and activated (CD25+) lymphocytes adjacent to C. parvum-infected epithelium. These results show that resident mucosal T lymphocytes can accumulate at the epithelium during C. parvum infection.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cattle
  • Cattle Diseases / immunology*
  • Cryptosporidiosis / immunology
  • Cryptosporidiosis / veterinary*
  • Cryptosporidium parvum / immunology*
  • Ileum / immunology
  • Ileum / parasitology
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / parasitology
  • Organ Culture Techniques
  • T-Lymphocytes*