Primate Biology最新文献

We report observations on fur-rubbing with leaves from Piper aduncum by a San Martín titi monkey, Callicebus oenanthe. Fur-rubbing occurred during the transition from the dry to the rainy season in a titi monkey group living in a forest fragment in the Moyobamba region of Peru. Since Piper leaves include very potent compounds that may affect ectoparasites, we tentatively interpret the observed fur-rubbing as self-medication.

Endometriosis is a poorly understood common debilitating women's reproductive disorder resulting from proliferative and ectopic endometrial tissue associated with variable clinical symptoms including dysmenorrhea (painful menstrual periods), dyspareunia (pain on intercourse), female infertility, and an increased risk of malignant transformation. The rhesus macaque (Macaca mulatta) develops a spontaneous endometriosis that is very similar to that seen in women. We hypothesized that specific major histocompatibility complex (MHC) alleles may contribute to the pathogenesis of endometriosis. As part of a collaboration between the Biomedical Primate Research Centre (BPRC) in the Netherlands and the New England Primate Research Center (NEPRC) in the United States, we analyzed DNA sequences of MHC class I (Macaca mulatta, Mamu-A1) and class II (Mamu-DRB) alleles from rhesus macaques with endometriosis and compared the allele frequencies with those of age-matched healthy macaques. We demonstrate that two MHC class I alleles are overrepresented in diseased macaques compared to controls: Mamu-A1*001, 33.3 % in BPRC animals with endometriosis vs. 11.6 % in healthy macaques ( $p=$  0.007), and Mamu-A1*007, 21.9 % NEPRC rhesus macaques vs. 6.7 %, ( $p=$  0.003). We provide evidence that select MHC class I alleles are associated with endometriosis in rhesus macaques and suggest that the disease pathogenesis contribution of MHC class I warrants further research.

Human immunodeficiency virus (HIV) comorbidities have become clinically more important due to antiretroviral therapy. Although therapy increases life expectancy, it does not completely suppress immune activation and its associated complications. The simian immunodeficiency virus (SIV)-infected rhesus macaque (Macaca mulatta) represents a valuable model for the investigation of SIV-associated diseases. Although cardiovascular (CV) changes are common in HIV-infected patients, there are only a few reports on the incidence of CV findings in SIV-infected animals. In addition, potential associations between pathohistological findings and hematological parameters are still unclear. We therefore conducted a retrospective analysis of 195 SIV-infected rhesus macaques that were euthanized with AIDS-related symptoms at the German Primate Center, Goettingen, over a 25-year period. Pathological findings were correlated with hematological data. The main findings included myocarditis (12.8 %), endocarditis (9.7 %), and arteriopathy (10.3 %) in various organs. Thrombocytopenia occurred more frequently in macaques with endocarditis or arteriopathy than in macaques without CV disease (80 % in animals with endocarditis, 60 % in animals with arteriopathy, $p<0.0001$ and $p=0.0016$ , respectively). Further investigations of the interaction between coagulation markers, proinflammatory cytokines, and biomarkers associated with endothelial dysfunction (e.g., D-dimers) and histological data (vascular wall structure) may unravel the mechanisms underlying HIV/SIV-associated CV comorbidities.

In this paper we report on two encounters between olive baboons (Papio anubis) and crowned eagles (Stephanoaetus coronatus) at Lake Manyara National Park, northern Tanzania. During these encounters olive baboons responded by giving alarm calls and all infants and juveniles rushed down from trees seeking cover under bushes or close proximity to adult conspecifics. In one of the events, alarm calls from banded mongoose (Mungos mungo) and rock hyraxes (Procavia capensis) most likely triggered alarm calling of vervet monkeys (Chlorocebus pygerythrus) which in turn prompted baboons to respond with alarm calls as well. In both observations, adult male baboons took the lead in climbing trees, threatening the eagle (staring, yawning, ground slapping) and chasing it away. The reaction of the baboons suggests that crowned eagles pose a threat at least for juvenile baboons at Lake Manyara National Park.

To safeguard patients, regulatory authorities require that new drugs that are to be given by the intravitreal (IVT) route are assessed for their safety in a laboratory species using the same route of administration. Due to the high similarity of ocular morphology and physiology between humans and nonhuman primates (NHPs) and due to the species specificity of many biotherapeutics, the monkey is often the only appropriate model. To this end, intravitreal administration and assessment of ocular toxicity are well established in cynomolgus monkeys (Macaca fascicularis). In contrast, the common marmoset monkey (Callithrix jacchus) is not a standard model for ocular toxicity studies due to its general sensitivity to laboratory investigations and small eye size. It was the purpose of the present work to study whether the marmoset is a useful alternative to the cynomolgus monkey for use in intravitreal toxicological studies. Six marmoset monkeys received repeated (every 2 weeks for a total of four doses) intravitreal injections of 10 or 20  $\mu$ L of a placebo. The animals were assessed for measurements of intraocular pressure (IOP), standard ophthalmological investigations and electroretinography (ERG). At the end of the dosing period, the animals were sacrificed and the eyes were evaluated histologically. ERG revealed similar results when comparing predose to end-of-study data, and there was no difference between the two dose volumes. A transient increase in the IOP was seen immediately after dosing, which was more pronounced after dosing of 20  $\mu$ L compared to 10  $\mu$ L. Ophthalmologic and microscopic observations did not show any significant changes. Therefore, it can be concluded that 10  $\mu$ L as well as 20  $\mu$ L intravitreal injections of a placebo are well tolerated in the marmoset. These results demonstrate that the common marmoset is an alternative to the cynomolgus monkey for intravitreal toxicity testing.

Several cases of spontaneous endometriosis in middle-aged to old rhesus macaques (Macaca mulatta) from the breeding colony of the German Primate Center were thoroughly characterized with regards to anatomical distribution and macroscopic appearance, histological differentiation and immunohistochemical profile including somatic markers, hormonal receptors, and proliferation indices. More than half of the examined animals (five of nine) were directly related to one breeding male, supporting a strong genetic predisposition. Histologically, four different types of endometriotic lesions, depending on the degree of ectopic endometrial gland and stromal differentiation (well differentiated, purely stromal, mixed differentiation, poorly differentiated), could be constantly identified within all animals. Immunohistochemistry (IHC) of cytokeratin (CK), vimentin, smooth muscle actin (SMA), desmin, estrogen (ER), and progesterone (PR) receptors as well as of the nuclear proteins Ki67 and p53 revealed varying staining patterns in the four different types of endometriosis differentiation and compared to normal endometrium. Purely stromal, mixed, or poorly differentiated lesions, especially, showed additional cytokeratin-positive stromal cells, whereas epithelial cells of endometriosis with mixed or poor differentiation increasingly expressed mesenchymal markers (vimentin, SMA). Hormonal receptor and Ki67 expression in well-differentiated endometriotic lesions mostly reflected that of normal endometrial tissue according to the cyclic phase of the animal, while the expression gradually diminished with decreasing grade of differentiation. However, increased nuclear accumulations of p53 antigen could only be continuously detected in epithelial cells of mixed or poorly differentiated endometriosis. Altogether, these findings support the pathogenetic theory of coelomic metaplasia, since the expression profiles of somatic markers in less differentiated forms closely resembled that of mesothelial cells. Thus, the four different histological types of endometriosis might display subsequent grades of differentiation in the course of time, with poorly differentiated types representing newly formed, immature lesions and well-differentiated types being older, fully differentiated forms, rather than being the outcome of dedifferentiation processes.

Overall, diseases of the vascular system are rarely observed entities among nonhuman primates that are commonly associated with systemic infections, septicemia or bacteremia. Rhesus monkeys infected with simian immunodeficiency virus (SIV) may develop a chronic occlusive arteriopathy of unknown etiology in late stages of the disease. This SIV associated arteriopathy is the only well-known specific vascular entity described in nonhuman primates. We herein report a unique case of granulomatous arteritis in a grey mouse lemur affecting multiple organs, which is not comparable to other disease entities formerly described in nonhuman primates. The features of the entity most closely resemble disseminated visceral giant cell arteritis in humans. A concise description of the disease is given, and the differential diagnoses are discussed. An idiopathic pathogenesis is suspected.

Humans and African great apes (AGAs) are naturally infected with several species of closely related malaria parasites. The need to understand the origins of human malaria as well as the risk of zoonotic transmissions and emergence of new malaria strains in human populations has markedly encouraged research on great ape Plasmodium parasites. Progress in the use of non-invasive methods has rendered investigations into wild ape populations possible. Present knowledge is mainly focused on parasite diversity and phylogeny, with still large gaps to fill on malaria parasite ecology. Understanding what malaria infection means in terms of great ape health is also an important, but challenging avenue of research and has been subject to relatively few research efforts so far. This paper reviews current knowledge on African great ape malaria and identifies gaps and future research perspectives.

In a landscape fragmented by agriculture, the extent to which forest-dwelling primates can use the matrix between fragments can be critical for their long-term survival. So far, the golden-headed lion tamarin (Leontopithecus chrysomelas), an endangered primate inhabiting the Atlantic Forest of south Bahia, is only known to use shaded cacao (Theobroma cacao) agroforests within the matrix. We report on the use of a rubber plantation by a group of golden-headed lion tamarins between August 2013 and January 2014. The group used the rubber plantation on 16 of the 22 observation days (73 %), and we recorded behaviours such as eating, grooming and sleeping, consistent with the use of the area as a home range. We also observed associations with Wied's marmosets (Callithrix kuhlii). The locations of group sightings were not uniformly spread across the entire area of the rubber plantation, suggesting preferred use of certain areas. The presence of resources such as jackfruits (Artocarpus heterophyllus) and epiphytic bromeliads may be attracting both species to these plantations. In addition to shaded cacao plantations, rubber plantations with the appropriate structure may be a viable option for increasing forest connectivity for both species in south Bahia, reconciling economic rubber production with primate conservation.