Visualization of the in vivo generation of donor antigen-specific effector CD8+ T cells during mouse cardiac allograft rejection: in vivo effector CD8+ T cell generation during allograft rejection.

BACKGROUND: An adoptive transfer system was used to study the fate of alloreactive CD8+ H-2Kb-specific TCR transgenic (DES+) T cells in vivo after transplantation. METHODS: A trace population of 2.0x10(6) CD8+DES+ T cells were adoptively transferred into syngeneic CBA.Ca (H-2k) mice 24 hr before transplantation of an H-2Kb+ or H-2Kb- cardiac allograft. RESULTS: H-2Kb specific T cells proliferated and produced interleukin-2 and interferon-gamma in response to H-2Kb+, but not H-2Kb- cardiac allografts. CD8+DES+ T cells that infiltrated the H-2Kb+ cardiac allografts developed a distinct cell surface and cytokine phenotype compared with the CD8+DES+ T cells that remained in the periphery. H-2Kb-specific graft infiltrating T cells (a) underwent a larger number of cell divisions (> =3), (b) increased in size, (c) up-regulated CD69, and (d) down-regulated CD62L. CONCLUSIONS: These results demonstrate that alloantigen-specific T cells can be monitored in vivo during the immune response to an allograft and that the fate of CD8+ T cells specific for the allogeneic class I molecules expressed by the graft is different between cells in the periphery and those that infiltrate the graft.

The visualization of T cell responses.

Transplanting allogeneic grafts is still significantly hampered by the rejection process, despite the use of powerful immunosuppressive agents. The T cell is recognized as playing a central role in the process of rejection, and it is believed that graft tolerance will ultimately be achieved by immunological manipulation of this cell (1, 2). As immunologists strive to define the role of the T cell in the fundamental processes of immunity and tolerance, new methods are emerging that will facilitate visualization of the T cells directly involved in the rejection response (3, 4). This overview addresses the visualization of T cell responses as made possible by these technological developments.

Mediterranean spotted fever in Marseille, France: correlation between prevalence of hospitalized patients, seroepidemiology, and prevalence of infected ticks in three different areas.

We report the results of a comparison of several epidemiologic and ecologic parameters affecting the incidence and seroprevalence of Mediterranean spotted fever (MSF) in northern, central, and southeastern Marseille, an area endemic for this disease. In northern Marseille, the incidence of hospitalized patients with MSF was 24.2/100,000 persons compared with 9.8/100,000 and 8.8/100,000 for the central and southeastern regions, respectively. The seroprevalence in sera from blood donors, determined by microimmunofluorescence and confirmed by Western blot assays, was higher in the northern region than in the other two areas (6.7% versus 3.6% and 2.4%, respectively). This higher prevalence of MSF in the northern part of the city may be related to a greater tick exposure due to a higher number of dogs (32.6/100 inhabitants versus 28.4/100 and 27.2/100 in the central and southeastern regions, respectively) and a higher rate of infection of dogs in the northern region (51.4% versus 43.5% and 39.9%, respectively). The ratio of spotted fever group rickettsia-infected ticks was similar in both the northern and southeastern areas (14.8% and 13.4% respectively), but lower in the central area of the city (8.9%), leading to a higher risk of having MSF after a tick bite in the northern and southeastern parts of Marseille.

[Evolution of populations of ticks (Ixodidae and Argasidae) in relation to artificialization of the environment in the French Alps. Epidemiologic effects]. / L'évolution des populations de tiques (Ixodidae et Argasidae) en relation avec l'artificialisation des milieux dans les Alpes françaises.

The results presented in this study are based on observations made during some 10 years in the French Alps and their surroundings. Forest clusters, as they still cover comparatively large areas, are considered the most favorable foci for several Ixodid species. Recent studies, however, have shown that environment modified by man also harbours large populations of ticks. The spreading of certain species around and even into cities is actually taking place. The following categories of tick species may be distinguished with reference to the artificialization process of the environment: 1. species occurring mainly in forest areas (Ixodes ricinus, I. trianguliceps); 2. species occurring in agricultural, suburban and preurban areas (Dermacentor reticulatus, Rhipicephalus turanicus); 3. species found in either natural wholes, burrows etc. or in constructions amidst rural areas (I. hexagonus, I. canisurga, R. pusillus); 4. species present exclusively in buildings, in either rural or urban areas (R. sanguineus, Argas reflexus). The vectorial role of the various tick species is discussed with regard to the artificialisation process. Particular attention is drawn to the appearance of new, and the extension of previously known foci of disease transmission in the vicinity of large cities.

[Vegetation analysis used for the detection of exophile tick populations in the south-east of France: the example Ixodes ricinus (Linne 1758) (acarina, ixodoidea)]. / L' analyse de la végétation appliquée á la détection des populations de tiques exophiles dans le sud-est de la France: l'exemple d'lxodes ricinus (Linné 1758) (acarina, Ixodoidea)

The cross-linking relation between the evidence of outside living tick populations and specific vegetation units allows for efficiently using the vegetation maps, and more especially the medium scale maps. Ixodes ricinus is referred to here as an example. The limitations of this data derived from such maps are evaluated by the authors. They suggest some means aiding in improving their efficiency through the knowledge of the ecological variables playing a role in the species settlement.

[Ecological study of Ixodes ricinus (Linné, 1758) (Acarina, Ixodoides) in southeastern France]. / Première contribution à l'étude écologique d'Ixodes ricinus (Linné, 1758) (Acarina, Ixodoidea) dans le Sud-Est de la France

Ixodes ricinus (LINNE, 1758) is being surveyed in the northern Alp and the Jura mountains. This species, quite often found in the mesophilous forests of the hills, preferably takes root in the forest clusters, where there is a mull type mild humus often covered with an abundant litter. Such plant layers maintain a high degree of moisture, which beneficially affects this species. Examinations performed for three years in a southern Jura's resort allow for securing a preliminary approximation as regards the seasonal population variations.

[Distribution and ecology of Ixodes trianguliceps (Birula, 1895) (Acarina, Ixodoidea) in France, particularly in the South-East]. / Contribution à la connaissance de la répartition et de l'écologie d'Ixodes trianguliceps (Birula, 1895) (Acarina, Ixodoidea) en France, et plus particulièrement dans les Sud-Est

Ixodes trianguliceps, parasite of insectivores and rodent mammals seems to be distributed throughout France, except in the mediterranean low altitude areas. This tick which does not manifest any parasitic specificty, has meanwhile preferred hosts (Clethrionomys glareolus, especially). At low altitudes, it likes forests, hedge-rows and heaths and at higher altitudes (Subalpine and alpine), opened area may be densely inhabited. The authors study the numerous concerned vegetal associations and precise the tick's phenology, particularly in the Bas-Dauphiné. They also discuss the many hypothesis concerning the still unknown ecology of I. trianguliceps free instars.

[Collecting with the flagging method and fixing on man of Ixodes (Trichotoixodes) frontalis (Panzer, 1795)]. / Collecte "au drapeau" et fixation sur l'homme d'Ixodes (Trichotoixodes) frontalis (Panzer, 1795).

As he was beginning to sort a batch of Ixodid ticks, collected with the flagging technique, the operator noticed that a female tick identified as Ixodes frontalis had fixed itself rapidly on the top of one of his finger. That species is usually considered as "strict-specific to birds". The low frequency of such a fixing on human beings, as for as we know, is of limited value from an epidemiological point of view.

[The colonization of forested areas by Ixodes ricinus (Linné, 1758) in France: use of the roe deer, Capreolus capreolus (L. 1758) as a biological marker]. / La colonisation des massifs forestiers par Ixodes ricinus (Linné, 1758) en France: utilisation du chevreuil, Capreolus capreolus (L. 1758) comme marqueur biologique.

The roe-deer is a wild animal for which Ixodes ricinus has a particular fondness. Its territory is similar to that of the ticks and it is a species which is found throughout France yet which rarely leaves its territory. Given these conditions, a systematic parasitological examination of the ungulate can provide pertinent information concerning the forests inhabited by the tick. Since it is difficult to conduct a thorough examination of a large number of roe-deer over a limited space of time and on a large territory, the best solution is to examine the hind feet (hooves and tarsus) of the animal which are widely covered by the preimaginal stages of the tick. This biological material is easily available to the extent that the measurements of the animals are often used for game management. A preliminary study was conducted in Dordogne (southwestern France). Out of the 137 pairs of feet examined more than 50% carried the tick species (larvae or nymphs). The critical analysis of the results obtained throughout the investigation enables us to be more specific about the conditions of application of the advocated method.

[Ecoepidemiology of Lyme borreliosis in the Rhône-Alps region. Distribution, ecological context, relationship to the distribution of Ixodes ricinus (Linnaeus, 1758)]. / Ecoépidémiologie de la borréliose de Lyme dans la région Rhône-Alpes. Répartition, contexte écologique, relations avec la distribution d'Ixodes ricinus (Linné, 1758).

The aim of the study was to precise the geographical repartition of Lyme borreliosis in the Rhône-Alpes district, to describe the ecological characteristics of the areas propitious to the disease, and to verify the vectorial competence of I. ricinus. The cases of Lyme disease were located by means of a questionnaire sent to 1156 physicians. The vector role of I. ricinus was studied by two ways: firstly by searching a correlation between the geographical repartition of the tick and that of cases, secondly by proving the Borrelia infection of the tick. Lyme disease is widely spread in the study area, mainly at the foothill level, its repartition is largely coinciding with that of I. ricinus which was found infected by B. burgdorferi (s.l.). However a few cases, located near the Mediterranean area, set an unanswered problem.

[Case report: electroconvulsive therapy during pregnancy]. / Electroconvulsivothérapie au troisième trimestre de grossesse. A propos d'un cas.

The treatment for psychiatric disorders in pregnancy remains difficult to implement. We report the case of a 28-year-old woman, 20 weeks pregnant when admitted in our psychiatric department. She presented severe depressive disorder, associated with agitation, and psychotic symptoms as delusion and hallucinations occurred. The patient had a history of recurrent mood disorders dating back to eight years before the current admission, including some atypical episodes (psychotic symptoms only), and alternating with free periods without any trouble. A non-specific personality disorder is also probably present. We first used antidepressant (clomipramine) and sedative phenothiazine drugs. Because of the lack of therapeutic efficacy, three weeks later we tried another pharmacologic prescription, that also failed to improve the patient' status. It was hence decided to proceed with electroconvulsive therapy. We describe here the management of the courses, especially the careful monitoring and the anesthetic features we employed, among which endotracheal intubation, oxygen supply, real-time ultrasonography, and recording uterine contractions and fetal heart rate. All theses measures were applied within a surgical-obstetrical theatre. Nine bifrontal courses were performed in five weeks. They rapidly and completely improved the psychiatric symptoms. No sign of fetal neither maternal bad tolerance occurred. While the patient had been authorized to leave hospital, in 34th weeks amenorrhea a routine ultrasonographic examination discovered worrying fetal ascites signs. After the emergency caesarean delivery, the male newborn child undergone immediately surgical treatment for vascular meconium peritonitis, but died nine days later with metabolic post-surgical troubles. This fatal outcome after electroconvulsive therapy leads us to discuss its possible involvement, and in a more general way the safety and place of this treatment in pregnancy psychiatric disorders. They remain critical situations in which therapeutic methods should be rapidly decided. The authors wish others practitioners to bring new case-reports in order to assess the ECT safety-use during pregnancy.

[Distribution and epidemiological value of Rhipicephalus turanicus. Ecology of the species in the South-Mediterranean part of France (author's transl)]. / Répartititon et intérêt épidémiologique de Rhipicepohalus turanicus (Pomerantsev, Matikasvili, Lototzki, 1940) (Acarina, Ixodoidea). Ecologie de cette espèce dans le Midi méditerranéen français.

Following a study of potential vectors of the boutonneuse Fever in the lower Rhône valley, the authors summarize knowledge concerning Rh. turanicus (biogeography, hosts, seasonal dynamics). Using their own work, they emphasize its distribution and ecology in the French mediterranean region: as an exophile species, frequently encountered because of the rich variety of its hosts (domestic and wild) and its adaptability to numerous human biotopes, it probably has a very significant epidemiological role.

Epidemiology of canine babesiosis in relation to the activity of Dermacentor reticulatus in southern Jura (France).

Dates of onset of canine babesiosis within a hyperendemic focus in France (Rhone Valley, south of Jura and north of the Alps) were compared to the seasonal population level of the adult stage of Dermacentor reticulatus over a 12-month period (December 1982-November 1983). Cases of babesiosis occurred in spring and fall when adult D. reticulatus were active. The fluctuations of the vector tick population and the onsets of canine babesiosis were also correlated with climatic changes: no tick activity or clinical cases of disease were detected in winter (low temperature) or in summer. The slight disparities observed between both distributions might be explained by various factors such as the development of immunity against the parasites, the intervals between tick bites and appearance of symptoms of the disease, or the asynchrony between different biotopes.

Isolation by a sensitive centrifugation cell culture system of 52 strains of spotted fever group rickettsiae from ticks collected in France.

Boutonneuse fever caused by Rickettsia conorii is transmitted mainly by the brown dog tick, Rhipicephalus sanguineus. We collected 540 ticks in Marseille, France, and tried to isolate as many strains of rickettsia as possible. Ticks were evaluated for the presence of rickettsia by the hemolymph test and by a new culture system, the centrifugation-shell vial technique. We avoided contamination in the culture system. Prior to ticks being submitted to the hemolymph test, they were disinfected. Only 5.6% (27 of 478) of the cultures were contaminated. A drop of hemolymph from each of 478 R. sanguineus ticks was cultured in two shell vials, and another drop was stained by the Gimenez method or indirect immunofluorescence. Since Gimenez staining in our hands was not satisfactory, comparison of the hemolymph test and culture is based on the results of indirect immunofluorescence. Thus, 50 of 369 (13.5%) examined ticks were hemolymph test positive, and 44 (11.9%) cultures were positive. After disinfection, another pool of 62 ticks were examined by the hemolymph test. The ticks were kept individually in a sterile environment. A few days later, the hemolymph of these ticks was collected again and cultured. The contamination rate was not significantly higher (6.4%) than in the above-described conditions. It allowed us to isolate eight more strains. Thus, we recommend screening ticks with the hemolymph test and culturing only the hemolymph test-positive ticks.

[Detection of the larva of Taenia multilocularis in 2 voles (Microtus arvalis and Clethrionomys glareolus) in a focus of alveolar echinococcosis in the Massif Central (France)]. / Mise en évidence de la larve du Taenia multiloculaire chez 2 campagnols (Microtus arvalis et Clethrionomys glareolus) dans le foyer d'échinococcose alvéolaire du Massif Central (France).

Small wild rodents were collected and examined during 1983-1984 to investigate parasite-host relationships of Echinococcus multilocularis in one habitat suitable for red foxes of Auvergne (France). The natural infestation of the liver of two different voles, Microtus arvalis and Clethrionomys glareolus, by the larval stage of the cestode is recorded for the first time. In the both cases, the larvae were fully developed and numerous protoscolices were present with some calcareous corpuscules; the expansion of the larvae involved several hepatic lobes in Microtus and was restricted to a single lobe in Clethrionomys. Epidemiological consequences of the receptivity of the two hosts are not yet investigated in the field. However several species of voles inhabiting the same endemic area and which are receptive to the larval stage of alveolar echinococcosis should be a favourable factor of durability for the cestodiasis of the foxes; so the parasite is able of surviving the cyclic and considerable but not simultaneous fluctuations of the three populations of voles which are locally implicated in the zoonosis: M. arvalis, C. glareolus and Arvicola terrestris, by changing from one species to the others.