Document Detail

Histological and immunohistological investigation of lymphoid tissue in the platypus (Ornithorhynchus anatinus).
MedLine Citation:
PMID:  10529053     Owner:  NLM     Status:  MEDLINE    
The gross and histological appearance and the distribution of T and B lymphocytes and plasma cells are described for lymphoid tissues obtained from 15 platypuses. The spleen was bilobed and surrounded by a thick capsule of collagen, elastic fibres and little smooth muscle. White pulp was prominent and included germinal centres and periarterial lymphoid sheaths. Red pulp contained haematopoietic tissue. A thin lobulated thymus was located within the mediastinum overlying the heart. The cortex of lobules consisted of dense aggregates of small and medium lymphocytes, scattered macrophages and few reticular epithelial cells. In the medulla, Hassall's corpuscles were numerous, lymphocytes were small and less abundant, and reticular cells were more abundant than in the cortex. Lymphoid nodules scattered throughout loose connective tissue in cervical, pharyngeal, thoracic, mesenteric and pelvic sites measured 790 +/- 370 microm (mean +/- S.D., n = 39) in diameter, the larger of which could be observed macroscopically. These consisted of single primary or secondary follicles supported by a framework of reticular fibres. Macrophages were common in the germinal centres. The platypus had a full range of gut-associated lymphoid tissue. No tonsils were observed macroscopically but histologically they consisted of submucosal follicles and intraepithelial lymphocytes. Peyer's patches were not observed macroscopically but histologically they consisted of several prominent submucosal secondary follicles in the antimesenteric wall of the intestine. Caecal lymphoid tissue consisted of numerous secondary follicles in the submucosa and densely packed lymphocytes in the lamina propria. Bronchus-associated lymphoid tissue was not observed macroscopically but was identified in 7 of 11 platypus lungs assessed histologically. Lymphoid cells were present as primary follicles associated with bronchi, as aggregates adjacent to blood vessels and as intraepithelial lymphocytes. The distribution of T lymphocytes, identified with antihuman CD3 and CD5, and B lymphocytes and plasma cells, identified with antihuman CD79a and CD79b and antiplatypus immunoglobulin, within lymphoid tissues in the platypus was similar to that described in therian mammals except for an apparent relative paucity of B lymphocytes. This study establishes that the platypus has a well-developed lymphoid system which is comparable in histological structure to that in therian mammals. It also confirms the distinctiveness of its peripheral lymphoid tissue, namely lymphoid nodules. Platypus lymphoid tissue has all the essential cell types, namely T and B lymphocytes and plasma cells, to mount an effective immune response against foreign antigens.
J H Connolly; P J Canfield; S J McClure; R J Whittington
Related Documents :
12819013 - Up-regulation of alg-2 in hepatomas and lung cancer tissue.
23428233 - Antisperm antibodies and fertility asociation.
10733483 - Urokinase-mediated fibrinolysis in the synovial fluid of rheumatoid arthritis patients ...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Journal of anatomy     Volume:  195 ( Pt 2)     ISSN:  0021-8782     ISO Abbreviation:  J. Anat.     Publication Date:  1999 Aug 
Date Detail:
Created Date:  1999-12-20     Completed Date:  1999-12-20     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  0137162     Medline TA:  J Anat     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  161-71     Citation Subset:  IM    
Department of Veterinary Anatomy and Pathology, University of Sydney, NSW, Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
B-Lymphocytes / cytology
Bronchi / immunology
Collagen / analysis
Elastic Tissue / anatomy & histology
Lymph Nodes / cytology
Lymphocyte Count
Lymphoid Tissue / anatomy & histology*,  cytology
Macrophages / cytology
Muscle, Smooth / anatomy & histology
Peyer's Patches / cytology
Plasma Cells / cytology
Platypus / immunology*
Reticulocytes / cytology
Spleen / anatomy & histology,  chemistry,  cytology
T-Lymphocytes / cytology
Thymus Gland / anatomy & histology,  chemistry,  cytology
Reg. No./Substance:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Changes in and factors related to loneliness in older men. The Zutphen Elderly Study.
Next Document:  Inhibition of dendrite formation in mouse melanocytes transiently transfected with antisense DNA to ...