Advanced Search

Home > Journals > Minerva Medica > Past Issues > Minerva Medica 2003 June;94(3) > Minerva Medica 2003 June;94(3):181-6

ISSUES AND ARTICLES   MOST READ   eTOC

CURRENT ISSUEMINERVA MEDICA

A Journal on Internal Medicine

Indexed/Abstracted in: Current Contents/Clinical Medicine, EMBASE, PubMed/MEDLINE, Science Citation Index Expanded (SciSearch), Scopus
Impact Factor 1,236

Frequency: Bi-Monthly

ISSN 0026-4806

Online ISSN 1827-1669

 

Minerva Medica 2003 June;94(3):181-6

    ORIGINAL ARTICLES

Fetal thymic medulla functional alterations in Down's syndrome

Papadopoulos N., Simopoulos C., Venizelos J., Kotini A., Skaphida P., Tamiolakis D.

Aim. Although the thymus is usually considered a specifically T cell organ, occasional mature B lymphocytes, B cell germinal centres and rarely plasma cells can be found in this organ, particularly in children. Ultrastructural studies have shown that these lie outside the epithelial enclosure and within the perivascular spaces of the medulla, the corticomedullary junction and septa, and this has led to a concept of 2 functional compartments of the thymus, namely an intraepithelial compartment and an extraepithelial (perivascular) compartment. These cells do not originate from the thymus but enter the organ via the bloodstream, at the 16th week of gestation. Our study points towards possible alterations in the functional histology of this lymphoid organ associated with immunization.
Methods. A quantitative comparison of B lymphocytes in the thymic medulla in embryos after involuntary abortion during the 1st and 2nd trimester of gestation and embryos with Down's syndrome, respectively, was performed.
Results. Our results showed: 1) A statistically significant difference in the number of B cells together with infrequent primary follicles in the cases of embryos with Down's syndrome over those after voluntary abortion, during the 20th week of gestation (p=0.013). 2) No statistically significant difference in the number of B cells in both categories during the 1st trimester of gestation (p=0.34) and the 24th week of gestation (p=0.14).
Conclusion. The occurrence of increased number of B cells along with primary follicles in the cases with Down's syndrome, in the 2nd trimester of gestation imply that the thymic medulla - at least part of it - works and behaves as a peripheral lymphoid organ receiving mature lymphocytes, and turning them from inactive to immunoefficient cells, in the affected fetuses.

language: English


FULL TEXT  REPRINTS

top of page