Junqueira, L. C. U.

English

Cadernos Espinosanos (E-Journal)

Rev. Inst. Med. trop. sao Pcmlo 10(:J):138-140, maio-junho, 1968 UDG 616.988 NOTE ON THE PRESENCE OF VIRUS-LIKE AGGREGA TES AND PARTICLES OF UNKNOWN ORIGIN IN THE TISSUES OF A COLUBRID SNAKE (XENODON MERREMII) L. C. U. JUNQUEIRA ( 1 ) SUMitIARíl Intracellular virus-like aggregates and extracellular particles of unknown ongm were found during the electron microscopic study of tissues of the ophidian Xerwdon merremn. ln 11 snakes studied, 4 presented virus-like aggregates formed by crystal like oriented particles with an average diameter of 500 A. INTRODUCTION During the observation of snake tissues 011 the electron microscope a serie of organs were observed whose cells contained virus-like aggregates. As the frequency of these particles was relatively high and recently attention has been drawn to the fact that reptiles and amphibia can be virus reservoirs (for literature see BURTON et al.1) we thought it of interest to publish these results. Small tissue fragments were fixed 111 MrLLONIG's ª osmium tetroxide phosphate buffer, dehidrated and embeded in Araldite according to LUFT 2 • Thin sections were double stained in uranyl acetate and lead hydroxide. Observation was performed in a Zeiss EM 9 electron microscope. Severa! sections of 2 to 4, fragments of each organ were observed. RESULTS AND DISCUSSION MATERIAL AND METHODS Eleven adults Xenodon merremii of both sexes collected at random in the State of São Paulo were used. The organs studied in the 11 snakes used were, the digestive glands and tract, adrenal gland, thyroid, hypophysis and lung. ln these animals observed 4 presented aggreg:ites witl1 a virus-like morphology in diíferent organs as shown in Table I. TABLE I Occurrence of virus-like aggregates in the cells of some organs of Xenodon merremii Snake number 3,459 3,555 3,602 3,624 Otgan (s) with aggregate Small ·intestine reabsorptive epithelium Adrenal gland "cortical" cells and capillary endothelial cells Adrenal gland "cortical" cells. Salivary gland epithelial cell. Lung enãothelial cel1. Large intestine epithelium. Th'yroid epithelial cell. Stomach capillary endothelium and superficial epithelium. (1) Laboratório de Fisiologia Celular. Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brasil l38 -,lllNQllF.inA, 1 .... <". L NOI('- on lhe pn:n•n,•(' or , ·i rus .. like ••~J!ft'~atci- and ~U-ll<-1~ o r u nknu\\ U ortgin ln tlw tlPSUf'!I ur ~t ••f>lul,rl<I Jomàl<(' <X<'tHJd011. tlH'ffCmii>. Ue-t•. Jmtt. !J!e,r. iror,. :,.:,;,, /'(mio 1(1: l 3.8-MO, Hl6S ~ .. -~- \ .r ' . \ \ r .. ~cpt. ~ l f 1 . ' , ~--~, •· i ~~} # - l ·• 1 Fig. 1 S mull aggrcgale ro und ln lhe e ndothcllnl <'ell or the slomn<'lt. f'i0,0011 X . ln M a m1lothcm-1l rmn , C' :\1 l:s ,·<'li memhr-an" n níl f-: lt endoplnsmic· rellc·ul um. J?Jg. :l A gg1'<'gnte ln n t hyrohl ep1-Lhcli:ll e-eu. Obser\'e ln thls rlg. n1HI tlt e n exl t he pl'esenc·e or n n f'leí'tron den!i:C outcr shell ln thl: 11.;u ·t k lt's. OMl'rly Mrnngf'ment. or I h" 1>a1•Uc-1es wlth li ('t'~l .Hin e, likt ~tru<·tu~. The ;;t1txn.>aatc l!i ln the ou tslde or the :ibundant rough <'r,<loplasmh' retlc·u lum. 60,000 X . r·tg. 3 - Aggreg:,tc.- í<mnd in <• :Hlr,...na l " ('ortex" ('('li, l n i\t ;_\ mlt04..•hon<1ri(ln anel nt thc• lt(t. or the 1nc1us1on a IIJ)W cIropte1. 60,000 X. r·tg. 4 - Another aggl'egat(' m :m t' ílren 31 ··corlex·· cell, 120,000 X. F'lg. 5 - F.X• trnr1..•lluhl1· a,;cgn_-~~t(' J):lrt.léles or u nknown o rígln h \ th4..~ ('Q1l nec·tlv(• 11.:-is\14..~ o r th(' s tom:if'h. Ob... . ervc íi jtl ll' l 'S lhàl mlg hl 1)(' <luc to l)ln.ary ífs~ion ( ;) 1'1'0\\$ • . l n ("OI. ('01:l;wnir (il)('l'S, 25.000 X. Fl)C, H Ano11w1· ;.1s;t~1't'gah' o r t h<.~ !<.l~me pnrtl('Jt•s round ln 1!l(' s,une tlssuC'. 40,000 X. 139 JUNQUEIRA, L. e. U. - Note on the presence of virus-like aggregates and particles of unlrnown origin in the tissues of a colubrid snake (Xenodon merremii). Rev. Inst. Med. trop. São Paulo 10: 138-140, 1968. As to the morphology of the aggregates, they always were formed by spherical parti-eles measuring approximately 500 A of diameter. The aggregates were of various sizes sometimes relatively small with 8 par-ticles appearing in section but usually larger (Figs. 1-2-3 and 4). They were always in-tracellular and free in the cells ground cy-toplasm, never surrounded by a membrane or in cellular organelles such as endoplasmic reticulum, nucleous, Golgi vacuoles, mito-chondria, etc. The spherical particles presented a distinct and relatively thick electron dense outer portion and usually were disposed in a or-derly arrangement simulating a crystaline structure ( Figs. 2-3 and 4). Between the spherical particles, small round electron dense elements with morphology re-sembling ribosomes were constantly observed. The highest incidence of aggregates was observed in capillary endothelial cells of the different organs studied. The electron microscope is not well adapted to survey the presence of vírus in animais collected in nature. Thus only some sections of 2 to 4 fragments of some but not ali organs of the snakes we studied. We used therefore a poor sampling method. Despite this fact the incidence of the inclusions is relativelly high and one is consequently led to suspect that it is probably much higher. It is in-teresting to correlate this observation with the data of BuRTON et al.1 who observed a high incidence (36.2%) of serum neutralizing antibodies to Western equine encephalitis in snakes of the genus Thamnophis. The Authors could also in some cases isolate the virus from the blood of these animais. They conclude that their data suggest a wide dis-tribution of W estern equine encephalitis in the snakes and frogs studied. These results agree with the observations that some cold blooded .animais can be susceptible to en-cephalitis vírus (THOMAS et ai. 4 and V OROB' EVA & LEVKOVICH 5 • ln one of the snakes studied (n.0 3,624) extracellular particles were also observed in the connective tissue of the stomach's wall ( Figs. 5 and 6) . The parti eles here were of much larger size ( diameter of approximately o 2,000 A) and were not aggregated in an orderly fashion. They presented a thick outer 140 portion and in some particles a dense gra-nular content was visible. Some morpho-logical aspects suggesÜng a binary fission were observable ( arrows in Figs. 5 and 6). Their aspect and size suggest more the possi-bility of being a submicroscopic microorga-nism of non virai nature. RESUMO Nota sôbre a presença de agregados viróides e partículas de origem desconhecida nos te-cidos de um ofídio (Xenodon merremii) O Autor descreve a presença de inclusões intracelulares com morfologia de vírus em te-cidos do ofídio Xenodon merremii. As par-tículas se dispõem em arranjo cristalino e o têm em média o diâmetro de 500 A. Foram encontradas em 4 das 11 cobras estudadas ao microscópio eletrônico. Foram também des-critas partículas extracelulares de origem desconhecida, com o diâmetro médio de o 2.000 A. ACKNOWLEDGEMENT The Author is grateful to the "Instituto Pinheiros" for donating the specimens used. REFERENCES 1. BURTON, A. N.; Me INTOCH, J. & REMPEL, J. G. - Western equíne encephalitis Vírus in Saskatchewan Garter Snakes an Leopard Frogs. Science 154: 1029-1031, 1966. 2. LUFT, J. - Improvements ín epoxy resín embedding methods. J. Bioph. & B-iochem. Cytol. 9:409-414, 1961. 3. MILLONIG, G. - Advantages of a phosphate buffer for Os o., solutíons in fixation. J. Appl. Phys. 32: 1637, 1961. 4. THOMAS, L. A.; EKLUND, E. M. & RUSH, W. A. - Susceptibilit;y of garter snakes (Thamnophis, sp) to WEE vírus. Proc. Soe. Exp. Biol. & Med. 99:697-698, 1958. 5. VOROB'EVA, M. S. & LEVKOVICH, E .. N. -- Susceptibility of cold-blooded animais to thick-borne encephalitis vírus. In F'ed. Proc. (Transl. Suppl.) 24:936-938, 1965. Recebido para publicarão em 25/10/1967. o 

Note on the presence of virus-like aggregates and particles of unknown origin in the tissues of a colubrid snake (Xenodon merremii)

https://www.revistas.usp.br/rimtsp/article/download/201649/185702

Note on the presence of virus-like aggregates and particles of unknown origin in the tissues of a colubrid snake (Xenodon merremii)

Abstract

Similar works

Full text

Available Versions

Cadernos Espinosanos (E-Journal)