Pesquisas sobre a imunidade da Framboesia tropica no homem: observações feitas em 33 superinoculações e 7 reinoculações

Como resultado das 40 experiências relatadas neste trabalho, as seguintes conclusões podem ser tiradas: 1) Dos 2 até aos 8 meses de molestia há na bouba uma grande resistência á superinoculação (13 experiências negativas em 15). Nas 2 experiências positivas, foram obtidas lesões atípicas (pianides): a) Tal resistência parece independer da presença de lesões boubaticas cutaneas e se fez sentir mesmo em casos com a lesão inicial exclusiva. b) Dentro desse período de molestia, tal resistência pode desaparecer com o tratamento: 2 doentes tratados aos 6 meses e reinoculados adquiriram bouba em tempo normal. Porém, um caso tratado aos 7 meses e reinoculado, desenvolveu uma pianide. Êste fato parece mostrar que essa resistência depende principalmente da presença da infecção ativa ou latente, raramente traduzindo uma imunidade no verdadeiro sentido do têrmo. c) No caso de emprego de homo-virus, essa resistência prolongou-se até um ano d molestia, havendo apenas um caso duvidoso em 10 inoculações. 2) Do 10º mês ao 4º ano de molestia, em 8 superinoculações observou-se uma resistência parcial que se traduziu de 2 modos, quanto à natureza da lesão atípica que se obteve no ponto inoculado; "lesão frustra papulo-eritematosa" (7 meses); e lesão semelhante ás "pianides" da infecção natural (1 vez), a qual permaneceu localizada sem manifestações metastaticas, até 4 meses de observação. a) Também este estado de resistência parcial, parece independer da presença de lesões boubaticas aparentes. b) Com o tratamento esse estado parece não se modificar: um doente tratado nesse período da molestia, reagiu à inoculação de modo semelhante, embora sem nenhuma manifestação clínica e com a R. Wa. negativa. Inegavelmente, essas "lesões frustras" e também as "pianides" obtidas, representam respostas de organismos que obtiveram vantagens na luta com a doença, possuindo um certo grau de imunidade, que é muitíssimo maior no caso das primeiras. 3) Depois do 5º ano de molestia, a resposta á superinoculação traduziu um estado de maior sensibilidade do organismo infectado. Observou-se no ponto inoculado uma reação precoce papulo-eritemato-ulcerosa, francamente necrotica e destrutiva, ao mesmo tempo que se verificou exacerbação das lesões dos pacientes, com grande infartamento gangliomar satélite. Até 18 meses depois, em um caso, a lesão obtida permaneceu localizada sem manifestações generalizadas. a) O tratamento não modificou tal estado. Doentes tratados ( e parcial ou totalmente curados), reagiram da mesma maneira à reinoculação dentro desse período da molestia. Apenas em um caso de mais de 5 anos (nº 40) não se obteve a lesão ulcero-necrotica. Era o único dos 13 experimentados que não tinha nem tivera lesões ulcero-gomoides destrutivas. por outro lado, 2 pacientes apresentando lesões gomo-ulcerativas, mas tendo menos de 3 anos de molestia, não deram a lesão ulcerativo-necrotica em resposta à superinoculação. (Experiências ns. 38 e 39). Interessante é que esta lesão ulcerativo-necrotica contém treponemas embora raros, e em evolução pode tomar o carater das lesões destrutivas gomo-ulcerativas peculiares ao chamado "período terciario" da doença, com as quais também se assemelha histopatológicamente. Sob o ponto de vista imunológico, esta lesão representa um estado de maior sensibilidade do organismo para o agente infeccioso. 4) Como o tratamento precoce perturba o desenvolvimento da imunidade, sob o ponto de vista epidemiológico, seria aconselhável aguardar o período terminal do chamado secundarismo, isto é da fase de generalização boubatica, para tratar os pacientes em Postos, hospitais ou ambulatórios pois, tais doentes poderiam se reinfestar uma vez retornados ao fóco. Claro que em campanhas terapeuticas profilaticas, as lesões "abertas" primo-secundarias, devem ser rapidamente eliminadas uma vez que são as mais contagiantes, por mais ricas em germes. 5) Existe na framboesia trópica uma verdadeira imunidade além de uma simples resistência á superinoculação devido a presença da infecção ativa ou latente. Com efeito, pacientes tratados em determinado período da molestia e curados clinica e sorologicamente, mostraram resistência parcial á reinoculação, reagindo de modo semelhante a outros do mesmo período de molestia e não tratados. 6) A imunidade na framboesia tropica se manifesta seja como uma resistência á superinoculação ou reinoculação seja como uma modificação da lesão boubatica inicial, seja, finalmente, como uma resistência á generalização da doença. 7) Os resultados das esperiências sugerem que as diferentes manifestações cutaneas da molestia são condicionadas até certo ponto pelo estado imunitario do organismo infectado. 8) Os diferentes gráus de imunidade, encontrados na framboesia trópica, estão até certo ponto relacionados com o tempo de doença. Porém, são atingidos mais ou menos ràpidamente, segundo o organismo infectado e, talvez segundo a virulência do treponema, do mesmo modo como os chamados "secundarismo" e 'terciarismo" da doença.

Functional analysis of the murine T lymphocyte immune response to a protozoan parasite, Leishmania tropica

The results presented in this review summarize a seirs of experiments designed to characterize the murine T cell imune response to the protozoan parasite Leishmania tropica. Enriched T cell populations and T cell clones specific for L. tropica antigens were derived from lymph nodes of primed mice and maintained in continous culture in vitro. These T lymphocytes were shown (A) to express the Lyt 1+ 3- cell surface phenotype, (B) to proliferate specifically in vitro in response to parasite antigens, together with a source of irradiated syngeneic macrophages, (C) to transfer antigen-specific delayed-type hypersensitivity (DTH) responses to normal syngeneic mice, (D) to induce specific activation of parasitized macrophages in vitro resulting in the destruction of intracellular parasites, (E) to provide specific helper activity for antibody responses in vitro in a hapten-carrier system. Protection studies using these defiened T cell populations should allow the characterization of parasite antigen(s) implicated in the induction of cellular immune responses beneficial for the host.

Alterações cutâneas do cão no Kala-Azar sul-americano

According to E. Chagas (1938), South-American Kala Azar is a widespread disease from the jungle, several cases being reported from North Brazil (Estado do Pará: Marajó Island, Tocantins and Gurupi river valleys; Estados do Piauí and Ceará: coast and hinterland). Other cases were found in Northeast Brazil (Estados de Pernambuco, Alagôas and Sergipe: coast and hinterland; Estado da Bahia: hinterland). A few cases were described from Estado de Mato-Grosso (Brazil), Provincia de Salta and Território do Chaco (Argentine), and Zona contestada do Chaco (Paraguai-Bolívia). A well defined secondary anemia associated with enlargement of the liver and spleen are the chief symptoms. Death usually occurs in cachexia and with symptoms of heart failure. Half the patients were children aged less than ten years (CHAGAS, CASTRO & FERREIRA, 1937). Quite exhaustive epidemiological researches performed by CHAGAS, FERREIRA, DEANE, DEANE & GUIMARÃES (1938) in Municipio de Abaeté (Estado do Pará, Brazil) gave the incidence of 1.48% for the natural infection in human, 4.49% in dogs, and 2.63% in cats. The infection was arcribed (CUNHA & CHAGAS, 1937) to a new species of Leishmania (L. chagasi). Latter CUNHA (1938) state, that it is identical to L. infantum. ADLER (1940) found that so far it has been impossible to distinguish L. chagasi from L. infantum by any laboratory test but a final judgment must be reserved until further experiments with different species of sandflies have been carried out. Skin changes in canine Kala Azar were signaled by many workers, and their importance as regards the transmission of the disease is recognized by some of them (ADLER & THEODOR, 1931, 2. CUNHA, 1933). Cutaneous ulcers in naturally infected dogs are referred by CRITIEN (1911) in Malta, by CHODUKIN & SCHEVTSCHENKO (1928) in Taschkent, by DONATIEN & LESTOCQUARD (1929) and by LESTOCQUARD & PARROT (1929) in Algeria, and by BLANC & CAMINOPETROS (1931) in Greece. Depilation is signaled by YAKIMOFF & KOHL-YAKIMOFF (1911) in Tunis, by YAKIMOFF (1915) in Turkestan. Eczematous areas or a condition described as "eczema furfurace" is sometimes noted in the areas of depilation (DONATIEN & LESTOCQUARD). The skin changes noticed by ADLER & THEODOR (1932) in dogs naturally infected with Mediterranean Kala Azar can be briefly summarized as a selective infiltration of macrophages around hair follicles including the sebaceous glands and the presence of infected macrophages in normal dermis. The latter phenomenon in the complete absence of secondary infiltration of round cells and plasma cells is the most striking characteristic of canine Kala Azar and differentiates it from L. tropica. In the more advanced stages the dermis is more cellular than that of normal dogs and may even contain a few small dense areas of infiltration with macrophages and some round cells and polymorphs. The external changes, i. e., seborrhea and depilation are roughly proportional to the number of affected hair follicles. In dogs experimentally infected with South-American Kala Azar the parasites were regularly found in blocks of skin removed from the living animal every fortnight (CUNHA, 1938). The changes noticed by CUNHA, besides the presence of Leishmania, were perivascular and diffuse infiltration of the cutis with mononuclears sometimes more marked near hair follicles, as well as depilation, seborrhea and ulceration. The parasites were first discovered and very numerous in the paws. Our material was obtained from dogs experimentally infected by Dr. A. MARQUES DA CUNHA< and they were the subject of a previous paper by CUNHA (1938). In this study, however, several animals were discarded as it was found that they did develop a superimposed infection by Demodex canis. This paper deals with the changes found in 88 blocks of skin removed from five dogs, two infected with two different canine strains, and three with two distinct human strains of South-American Kala Azar. CUNHA'S valuable material affords serial observations of the cutaneous changes in Kala Azar as most of the blocks of skin were taken every fortnight. The following conclusions were drawn after a careful microscopic study. (1) Skin changes directly induced in the dog by the parasites of South-American Kala Azar may b described as an infiltration of the corium (pars papillaris and upper portion of the reticular layer) by histocytes. Parasites are scanty, at first, latter becoming very numerous in the cytoplasm of such cells. Sometimes the histocytes either embedding or not leishman bodies appear as distinct nodes of infiltration or cell aggregations (histocytic granuloma, Figs. 8 and 22) having a perivascular distribution. The capillary loops in the papillae, the vessels of the sweat glands, the subpapillary plexus, the vertical twigs connecting the superficial and deep plexuses are the ordinary seats of the histocytic Kala Azar granulomata. (2) Some of the cutaneous changes are transient, and show spontaneous tendency to heal. A gradual transformation of the histocytes either containing or not leishman bodies into fixed connective tissue cells or fibroblasts occut and accounts for the natural regression just mentioned. Figs. 3, 5, 18, 19 and 20 are good illustrations of such fibroblastic transformation of the histocytic Kala Azar granulomata. (3) Skin changes induced by the causative organism of South-American Kala Azar are neither uniform nor simultaneous. The same stage may be found in the same dog in different periods of the disease, and not the same changes take place when pieces from several regions are examined in the same moment. The fibroblastic transformation of the histocytic granulomata marking the beginning of the process of repair, e. g., was recognised in dog C, in the 196th as well as in the 213rd (Fig. 18) and 231st (Fig. 19) days after the inoculation. (4) The connective tissue of the skin in dogs experimentally infected with South-American Kala Azar is overflowed by blood cells (monocytes and lymphocytes) besides the proliferation in situ of undifferentiated mesenchymal cells. A marked increase in the number of cells specially the "ruhende Wanderzellen" (Figs. 4 and 15) is noticed even during the first weeks after inoculation (prodomal stage) when no leishman bodies are yet found in the skin. Latter a massive infiltration by amoeboid wandering cells similar to typical blood monocytes (Fig. 21) associated to a small number of lymphocytes and plasma cells (Figs. 9, 17, 21, and 24) indicates that the emigration of blood cells...

A soro-aglutinação das Leishmanias

The first agglutination experiments (Tables 1 and 2) showed that the serum obtained with any one strain of Leishmania, agglutinates all the others even of another species. This finding reveals the existence of a common antigen. However as the titre of agglutination did not permit a sharp differentiation of species we tried the adsorption method. The first adsorption tests made demonstrated differences in antigenic constitution between a strain of. L. donovani on one hand and strains of L. tropica or L. brasiliensis on the other. Further experiments in which L. chagasi was tested against the other species revealed that the former was antigenically different from the others. These tests were performed by adsorbing an anti-chagasi serum with organisms belonging to the other species or, conversely, adsorbing with L. chagasi sera prepared against the other species (See Tables 9 to 24). On the other hand, the adsorption of a serum prepared against one strain of l. chagasi by another of the same species showed that they had identifical antigenie constitution. These findings suggested the possibility of separating different species of Leishmania by this method. However, tests to separate the other species from one to another gave inconclusive results. (See Tables 27 to 35). It was soon observed that all the strains of L. chagasi were of recent isolation while all the others had been maintained in artificial culture media for a long time. We were led to believe that this condition was responsible for the differences in behaviour encountered. Accordingly, recently isolated strains of L. brasiliensis and L. donovani were tested and shown to be antigenically similar to strains of L. chagasi also recently isolated. The conclusion may be drawn that all strains have the same antigenic constitution when freshly isolated. It has been noted that when a serum which has been prepared against a freshly isolated is adsorbed with an old strain, the amount of agglutinins left free, is much smaller than when a serum prepared against an old strain is adsorbed with a newly isolated strain. At first, we thought to explain this by the low titre of the serum. However, the amount of agglutinins left free was not larger when higher titre serum was tested. The results do not corroborate the view of a special antigen being present in recently isolated strains (vi antige) but rather that the phenomenon is dependent on differences of the amount of the common antigen, more abundant in recent strains. In order to make this clear, experiments were made in which equal amounts of a serum prepared against a newly isolated strain were adsorbed by equal amounts, by weight, of, on one hand, a new strain, and the other an old strain. The resulting adsorbed sera were then titrated. (Table 44). Results showed that newly isolated strains adsorb a larger amount of agglutinins (Tables 44, 45). Two hypothesis have bem advanced to explain the stronger adsorbing qualities of the newly isolated strains. 1° - these strains possess larger amounts of the common antigen and 2° - they contain a vi antigen which adsorbed by the new strain together with the common antigen is the cause of their larger adsorbing capacity. To find out which of the two hypothesis corresponds to the reality a new experiment was made, similar to the one summarized in table 44. The adsorbed sera were made to act on a recently isolated strain as well as on an old one. The latter, not containing the vi antigen, the difference seen when sera act on new strains should not be observed here in the case of this antigen being responsible for the differences in adsorbing properties. The difference persisting, the indication would be that the greater adsorbing capacity of recently isolated strains was really related to larger amounts of the common antigen present (Tables 46 and 47). The results of the experiment excluded the possibility of the vi antigen being responsible. Other experiments, (Tables 48 to 53) using a 3 year old strain, demonstrated the modification in its antigenic constitution during the period it was maintained in cultures.

Characterization of Endotrypanum Parasites Using Specific Monoclonal Antibodies

A large number of Endotrypanum stocks (representing an heterogeneous population of strains) have been screened against a panel of monoclonal antibodies (MAbs) derived for selected species of Endotrypanum or Leishmania, to see whether this approach could be used to group/differentiate further among these parasites. Using different immunological assay systems, MAbs considered specific for the genus Endotrypanum (E-24, CXXX-3G5-F12) or strain M6159 of E. schaudinni (E-2, CXIV-3C7-F5) reacted variably according to the test used but in the ELISA or immunofluorescence assay both reacted with all the strains tested. Analyses using these MAbs showed antigenic diversity occurring among the Endotrypanum strains, but no qualitative or quantitative reactivity pattern could be consistently related to parasite origin (i.e., host species involved) or geographic area of isolation. Western blot analyses of the parasites showed that these MAbs recognized multiple components. Differences existed either in the epitope density or molecular forms associated with the antigenic determinants and therefore allowed the assignment of the strains to specific antigenic groups. Using immunofluorescence or ELISA assay, clone E-24 produced reaction with L. equatorensis (which is a parasite of sloth and rodent), but not with other trypanosomatids examined. Interestingly, the latter parasite and the Endotrypanum strains cross-reacted with a number of MAbs that were produced against members of the L. major-L. tropica complex

Zinc Sulphate in the Treatment of Cutaneous Leishmaniasis: an in Vitro and Animal Study

This study was designed to evaluate the effectiveness of zinc sulphate both in vitro and in an animal model against both strains of old world cutaneous leishmaniasis. The in vitro sensitivities of promastigotes and axenic amastigotes of both Leishmania major and L. tropica to zinc sulphate was determined, the LD50 calculated and compared to the standard treatment for cutaneous leishmaniasis pentavalent antimony compounds. The results show that the two forms of both strains were sensitive to zinc sulphate and their respective LD50 were lower compared to the pentavalent antimony compound. Furthermore the sensitivities of the forms of both strains were tested using a simple slide method and compared to results of the standard method. To confirm this result, zinc sulphate was administered orally to mice infected with cutaneous leishmaniasis both therapeutically and prophylactically. Results showed that oral zinc sulphate was effective in both treatment and prophylaxis for cutaneous leishmaniasis. These results encourage the use of oral zinc sulphate in the treatment of cutaneous leishmaniasis clinically.

The origin and dispersion of human parasitic diseases in the Old World (Africa, Europe and Madagascar)

The ancestors of present-day man (Homo sapiens sapiens) appeared in East Africa some three and a half million years ago (Australopithecs), and then migrated to Europe, Asia, and later to the Americas, thus beginning the differentiation process. The passage from nomadic to sedentary life took place in the Middle East in around 8000 BC. Wars, spontaneous migrations and forced migrations (slave trade) led to enormous mixtures of populations in Europe and Africa and favoured the spread of numerous parasitic diseases with specific strains according to geographic area. The three human plasmodia (Plasmodium falciparum, P. vivax, and P. malariae) were imported from Africa into the Mediterranean region with the first human migrations, but it was the Neolithic revolution (sedentarisation, irrigation, population increase) which brought about actual foci for malaria. The reservoir for Leishmania infantum and L. donovani - the dog - has been domesticated for thousands of years. Wild rodents as reservoirs of L. major have also long been in contact with man and probably were imported from tropical Africa across the Sahara. L. tropica, by contrast, followed the migrations of man, its only reservoir. L. infantum and L. donovani spread with man and his dogs from West Africa. Likewise, for thousands of years, the dog has played an important role in the spread and the endemic character of hydatidosis through sheep (in Europe and North Africa) and dromadary (in the Sahara and North Africa). Schistosoma haematobium and S. mansoni have existed since prehistoric times in populations living in or passing through the Sahara. These populations then transported them to countries of Northern Africa where the specific, intermediary hosts were already present. Madagascar was inhabited by populations of Indonesian origin who imported lymphatic filariosis across the Indian Ocean (possibly of African origin since the Indonesian sailors had spent time on the African coast before reaching Madagascar). Migrants coming from Africa and Arabia brought with them the two African forms of bilharziosis: S. haematobium and S. mansoni.

Pseudascarophis brasiliensis sp. nov. (Nematoda: Cystidicolidae) parasitic in the Bermuda chub Kyphosus sectatrix (Perciformes: Kyphosidae) from southeastern Brazil

A new species of Pseudascarophis (Nematoda: Cystidicolidae) found in the stomach of Kyphosus sectatrix (Linnaeus) (Kyphosidae), off Rio de Janeiro, Brazil, is described. The new species can be differentiated from the other congeners by the presence of lateral alae, distinct but inconspicuous cephalic papillae at the anterior end, three pairs of precloacal and one pair of adcloacal papillae in males, egg morphology and morphometry of glandular oesophagus and spicules. Pseudascarophis tropica is transferred to Ascarophis as Ascarophis tropica (Solov'eva) comb. n. due to its ambiguous diagnosis.

Revisão taxonômica das espécies brasileiras de abelhas do gênero Lestrimelitta Friese (Hymenoptera, Apidae, Meliponina)

Revisão taxonômica das espécies de abelhas do gênero Lestrimelitta Friese (Hymenoptera, Apidae, Meliponina) que ocorrem no Brasil. Com base em caracteres morfológicos, como aqueles relacionados com a pilosidade, o formato do espiráculo propodeal, as distâncias interorbitais e o comprimento do esporão mesotibial, são reconhecidas catorze espécies, seis das quais novas para a Ciência: L. ciliata. sp. nov., L. maracaia sp. nov., L. similis sp. nov., L. spinosa sp. nov., L sulina. sp. nov. e L. tropica sp. nov. São designados lectótipos para Trigona (Lestrimelitta) limao var. rufipes Friese, 1903 e Trigona (Lestrimelitta) limao var. rufa Friese, 1903. O macho de L. limao (Smith, 1863) é descrito pela primeira vez. É apresentada também uma diagnose das seguintes espécies: L. ehrhardti Friese, 1931; L. glaberrima Oliveira & Marchi, 2005; L. glabrata Camargo & Moure, 1989; L. monodonta Camargo & Moure, 1989; e L. nana Melo, 2003. São apresentados chaves de identificação para operárias e machos, ilustrações e mapas de ocorrência.

Desenvolvimento Inicial de Duas Variedades de Cana-de-açúcar Inoculadas com Bactérias Diazotróficas

RESUMO A cana-de-açúcar é uma cultura de grande destaque na economia, em razão da produção de açúcar, etanol e energia. Tecnologias que possam contribuir para o aumento da produtividade e qualidade da cultura com mínimos danos ao meio ambiente são necessárias. Objetivou-se avaliar a produção de ácido indol acético de cinco estirpes de bactérias diazotróficas e o efeito da inoculação delas na brotação de duas variedades de cana-de-açúcar, RB867515 e IACSP95-5000. A produção de auxina foi determinada pelo teste colorimétrico, usando o reagente de Salkowski. Para avaliar a germinação, foi conduzido um experimento em casa de vegetação, utilizando-se delineamento experimental em blocos ao acaso com quatro repetições e sete tratamentos: controle não inoculado; inoculação mista com as cinco estirpes e inoculação individual com Gluconacetobacter diazotrophicus (Gd) estirpe BR11281T(PAL-5T), Herbaspirillum seropedicae (Hs - BR11335 = HRC54), Herbaspirillum rubrisubalbicans (Hr - BR11504 = HCC103), Burkholderia tropica (Bt - BR11366T = PPe 8 T) e Azospirillum amazonense (Aa - BR11145 = CBAMc). As bactérias mais eficientes na produção de auxina foram Hs e Hr, declinando 48 h após o crescimento. Hr, Aa e Bt aumentaram o índice de velocidade de germinação e o número de brotações nas duas variedades. Na var. RB867515, a velocidade de germinação ainda foi positivamente influenciada pela inoculação mista, sendo o mesmo observado pela inoculação de Gd na var. IACSP95-5000.