Hostname: page-component-84b7d79bbc-g7rbq Total loading time: 0 Render date: 2024-07-26T09:04:39.275Z Has data issue: false hasContentIssue false
  • English
  • Français

Cephalic and Pharyngeal Structures in Microfilariae Revealed by Staining

Published online by Cambridge University Press:  05 June 2009

B. R. Laurence  and
M. G. Simpson
B. R. Laurence
Affiliation:
Department of Entomology, London School of Hygiene and Tropical Medicine
M. G. Simpson
Affiliation:
Department of Entomology, London School of Hygiene and Tropical Medicine
Get access Rights & Permissions [Opens in a new window]

Extract

(1) Staining methods using paraldehyde-fuchsin, chrome-haematoxylin, and alcian blue or astra blue following oxidation, have demonstrated the shape of the hook and other structures on the cephalic space of microfilariae. These structures are described for three species of the genus Brugia, B. malayi, B. pahangi and B. patei, and are compared with the related structures found in the genera Wuchereria, Loa, Cardiofilaria, Onchocerca, Mansonella, Dipetalonema and Litomosoides.

(2) In Brugia the hook of the microfilaria is V-shaped and is supported basally by a pair of transverse basal pieces which are closely associated with an oral ring. Similar structures are found in the microfilariae of Wuchereria and Loa except that in Loa the hook is supported below by a semi-circular arch. In Brugia there is a row of three spines transversely on the cephalic space opposite the hook complex, the spines being markedly shorter in B. patei than in the other two species; in Wuchereria there is a single transverse row of four spines, and in Loa there are two or three transverse rows of spines, No spines arranged opposite the hook complex were observed in the other genera. The hook and associated structures in Cardiofilaria are similar in arrangement to those of Loa, and the small structures in Mansonella can possibly be derived from a similar arrangement. In Onchocerca the hook has the appearance of a broad plate and in Dipetalonema perstans part of the surface of the cephalic space appears to be involved with the small pointed “hook”. In Litomosoides the tip of the cephalic space is covered by a helmet-like structure carrying a pointed beak-like projection.

(3) It is suggested, from their staining reactions, that the cephalic structures of microfilariae are particularly rich in disulphide bonds, suggesting the presence of cystine.

(4) The staining methods also demonstrate an internal thread of tissue in microfilariae which extends in Brugia from the tip of the cephalic space back to the innen korper. A similar thread is present in the microfilaria of Wuchereria, Loa, Cardiofilaria and Mansonella but was not observed in the other genera, although a short thread of tissue was stained in the cephalic space in Onchocerca and Litomosoides. In Brugia, the buccal capsule, the pharynx and the pharyngo-intestinal valve develop around the pharyngeal thread of the microfilaria. The extreme end of the thread, around which the pharyngo-intestinal valve develops, differs in its staining reactions from the rest of the thread.

(5) The staining reactions of the pharyngeal thread in the microfilaria of Brugia show resemblances to those of “elastic” fibres in other invertebrates and oxytalan fibres of vertebrates. The pharyngeal thread appears to contain an acid mucopolysaccharide component.

(6) The possible functions of the cephalic and pharyngeal structures in the microfilariae are discussed briefly.

(7) A staining routine for demonstrating the structures described in this paper is given in an appendix.

Type
Research Article
Information
Journal of Helminthology , Volume 42 , Issue 3-4 , September 1968 , pp. 309 - 330
Copyright
Copyright © Cambridge University Press 1968

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Adams, C. W. M. and Sloper, J. C., 1955.—“Technique for demonstrating neurosecretory material in the human hypothalamus.” Lancet, 1955, 1, 651–652.CrossRefGoogle Scholar
Anderson, R. C., 1957.—“Observations on the life cycles of Diplotriaenoides translucidus Anderson and members of the genus Diplotriaena.” Can. J. Zool., 35, 15–24.CrossRefGoogle Scholar
Barka, T. and Anderson, P. J., 1965.—Histochemistry. Theory, Practice and bibliography, New York, Evanston and London.Google Scholar
Cameron, M. L. and Steele, J. E., 1959.—“Simplified aldehyde-fuchsin staining of neurosecretory cells.” Stain Technol., 34, 265–266.CrossRefGoogle ScholarPubMed
Casselman, W. G. B., 1962.—Histochemical Technique. London and New York.Google Scholar
Duke, B. O. L. and Lewis, D. J., 1964.—“Studies on factors influencing the transmission of onchocerciasis. III. Observations on the effect of the peritrophic membrane in limiting the development of Onchocerca volvulus microfilariae in Simulium damnosum.” Ann. trop. Med. Parasit., 58, 83–88.CrossRefGoogle Scholar
Elder, H. Y. and Owen, G., 1967.—“Occurrence of ‘elastic’ fibres in invertebrates.” J. Zool., Lond., 152, 1–8.CrossRefGoogle Scholar
Elftman, H., 1959.—“Aldehyde-fuchsin for pituitary cytochemistry.” J. Histochem. Cytochem., 7, 98–100.CrossRefGoogle ScholarPubMed
Esslinger, J. H., 1962.—“Behaviour of microfilariae of Brugia pahangi in Anopheles quadrimaculatus.” Am. J. trop. Med. Hyg., 11, 749–758.CrossRefGoogle Scholar
Feng, L.-C., 1936.—“The development of Microfilaria malayi in A. hyrcanus var. sinensis Wied.” Chinese med. J., Suppl., 1, 345–367.Google Scholar
Fülleborn, F., 1959.—“Filariosen des Menschen.” In Handbuch der pathogenen Mikroorganismen, 6, 1039–1224.Google Scholar
Fullmer, H. M., 1960a.—“Effect of peracetic acid on the enzymatic digestion of various mucopolysaccharides: reversal of the PAS staining reaction of mucin.” J. Histochem. Cytochem., 8, 113–121.CrossRefGoogle ScholarPubMed
Fullmer, H. M., 1960b.—“A comparative histochemical study of elastic, pre-elastic and oxytalan connective tissue fibres.” J. Histochem. Cytochem., 8, 290–295.CrossRefGoogle Scholar
Fullmer, H. M., and Lillie, R. D., 1958.—“The oxytalan fibre: a previously undescribed connective tissue fibre.” J. Histochem. Cytochem., 6, 425–430.CrossRefGoogle Scholar
Gomori, G., 1950.—“Aldehyde-fuchsin: a new stain for elastic tissue.” Am. J. clin. path., 20, 665–666.Google ScholarPubMed
Gurr, G. T., 1963.—Biological staining methods. London.Google Scholar
Hyman, L. H., 1951.—The Invertebrates: Acanthocephala, Aschelminthes, and Entoprocta. New York, Toronto and London.Google Scholar
Laurence, B. R. and Pester, F. R. N., 1961.—“The behaviour and development of Brugia patei (Buckley, Nelson and Heisch, 1958) in a mosquito host, Mansonia uniformis Theobald.” J. Helminth., 35, 285–300.CrossRefGoogle Scholar
Manson, P., 1898. —Tropical Diseases. A manual of the diseases of warm climates. London, Paris, New York and Melbourne.Google Scholar
McManus, J. F. A. and Mowry, R. W., 1964.—Staining Methods. Histologic and histochemical. New York, Evanston and London.Google Scholar
Nelson, G., 1961.—“On Dipetalonema manson-bahri n.sp., from the spring-hare, Pedetes surdaster larvalis, with a note on its development in fleas.” J. Helminth., 35, 143–160.CrossRefGoogle ScholarPubMed
Paget, G. E. and Eccleston, E., 1959.—“Aldehyde-thionin : a stain having similar properties to aldehyde-fuchsin.” Stain Technol., 34, 223–226.CrossRefGoogle Scholar
Pearse, A. G. E., 1961.—Histochemistry. Theoretical and Applied. London.Google Scholar
Sawyer, T. K., Rubin, E. F. and Jackson, R. F., 1965.—“The cephalic hook in microfilariae of Dipetalonema reconditum in the differentiation of canine microfilariae.” Proc. helminth. Soc., Wash., 32, 15–20.Google Scholar
Taylor, A. E. R., 1960.—“Studies on the microfilariae of Loa loa, Wuchereria bancrofti, Brugia malayi, Dirofilaria immitis, D. repens and D. aethiops.” J. Helminth., 34, 13–26.CrossRefGoogle ScholarPubMed
Thompson, S. W., 1966.—Selected histochemical and histopathological methods. Illinois.Google Scholar
Treadgold, C. H., 1920.—“On a filaria, Loa papionis n.sp., parasitic in Papio cynocephalus.” Parasitology, 12, 113–135.CrossRefGoogle Scholar