Fur mites are one of the most common ectoparasites of laboratory mice and traditionally are diagnosed through surveillance of individual colony animals. Although multiple diagnostic modalities exist, ...few recommendations suggest optimal testing methods, target colony populations, or sampling sites. We compared the fur pluck and sticky paper techniques for the diagnosis of Myocoptes musculinus in naturally infested immunocompetent mice and evaluated the effect of mouse age and sampling site on the efficacy of fur plucks. We found that the sticky paper technique was more likely to detect fur mites than were fur plucks. Housing mice individually increased the incidence of false-negative fur pluck tests, whereas sensitivity was equivalent for preweanling and adult mice. The ventral abdomen was the most likely single sampling location to detect evidence of any stage of Myocoptes musculinus, but fur mite eggs were overrepresented on the neck. We found that the surface temperature of the murine neck surface was warmer than was the rump and therefore may represent a unique microenvironment for fur mite egg development. Given our findings, we recommend that group-housed adult or preweanling mice should be selected for Myocoptes musculinus evaluation and that the ventral abdomen should be sampled. When possible, the postmortem sticky paper technique should be used rather than the antemortem fur pluck method.
Macaques are an excellent model for many human diseases, including reproductive diseases such as endometriosis. A long-recognized need for early biomarkers of endometriosis has not yet resulted in ...consensus. While biomarker studies have examined many bodily fluids and targets, cervicovaginal secretions have been relatively under-investigated. Extracellular vesicles (EVs, including exosomes and microvesicles) are found in every biofluid examined, carry cargo including proteins and RNA, and may participate in intercellular signaling. Little is known about EVs in the cervicovaginal compartment, including the effects of reproductive tract disease on quantity and quality of EVs.
In September 2014, a 9-year-old rhesus macaque was diagnosed with endometriosis at The Johns Hopkins University School of Medicine. Ultrasound-guided fine needle aspiration of a cyst and subsequent laparotomy confirmed diagnosis. The animal was sent to necropsy following euthanasia for humane reasons. Perimortem vaginal swabs and cervicovaginal lavages were obtained. Using a combination of methods, including ultracentrifugation and NanoSight visualization technology, approximate numbers of EVs from each sample were calculated and compared to populations of EVs from other, reproductively normal macaques. Fewer EVs were recovered from the endometriosis samples as compared with those from reproductively healthy individuals.
To our knowledge, this is the first examination of EVs in primate cervicovaginal secretions, including those of a macaque with endometriosis. This case study suggests that additional research is justified to determine whether quantification of EVs-or their molecular cargo-in cervicovaginal lavage and vaginal swabs may provide a novel, relatively non-invasive diagnostic for primate endometrial disease or other reproductive tract diseases.
Although platelets are the cellular mediators of thrombosis, they are also immune cells. Platelets interact both directly and indirectly with immune cells, impacting their activation and ...differentiation, as well as all phases of the immune response. Megakaryocytes (Mks) are the cell source of circulating platelets, and until recently Mks were typically only considered bone marrow-resident (BM-resident) cells. However, platelet-producing Mks also reside in the lung, and lung Mks express greater levels of immune molecules compared with BM Mks. We therefore sought to define the immune functions of lung Mks. Using single-cell RNA sequencing of BM and lung myeloid-enriched cells, we found that lung Mks, which we term MkL, had gene expression patterns that are similar to antigen-presenting cells. This was confirmed using imaging and conventional flow cytometry. The immune phenotype of Mks was plastic and driven by the tissue immune environment, as evidenced by BM Mks having an MkL-like phenotype under the influence of pathogen receptor challenge and lung-associated immune molecules, such as IL-33. Our in vitro and in vivo assays demonstrated that MkL internalized and processed both antigenic proteins and bacterial pathogens. Furthermore, MkL induced CD4+ T cell activation in an MHC II-dependent manner both in vitro and in vivo. These data indicated that MkL had key immune regulatory roles dictated in part by the tissue environment.
An 8‐year‐old, male Rhesus macaque (Macaca mulatta), previously used for dengue virus (DENV) vaccine research with viral challenge, was presented with adult‐onset, chronic, cyclic thrombocytopenia. ...Platelet number, morphology, and function were evaluated by automated hematology, peripheral blood smears, electron microscopy, flow cytometry, and impedance aggregometry. Bone marrow was evaluated by cytology. Both serum anti‐dengue nonstructural protein 1 (NS1) antibodies and anti‐platelet antibodies were detected by ELISA. Platelet characterization showed a lack of aggregation to all agonists (ADP, ASP, and collagen), increased activation with increased expression of surface marker (HLA‐ABC), and an absence of surface receptor GPIX during clinical episodes of petechiae and ecchymoses, even in the presence of normal platelet counts. Bone marrow aspirates identified potential mild megakaryocytic hypoplasia. All platelet functions and morphologic attributes were within normal limits during clinically normal phases. Presence of anti‐dengue NS1 serum antibodies confirmed a positive DENV titer 8 years postvaccination. Based on the history and clinical findings, a primary differential diagnosis for this chronic, cyclic platelet pathology was autoimmune platelet destruction with potential bone marrow involvement.
Evidence suggesting that HIV pathogenesis differs by sex, a variable known to influence the extent and breadth of immune responses in health and disease continues to accumulate. Host factors that ...promote or inhibit HIV replication may do so in a way that varies by sex. Prior studies using cultured human macrophages demonstrated that osteopontin (OPN)/secreted phosphoprotein-1 (SPP1) stimulates HIV replication. To test whether OPN has the same positive impact on virus replication at the level of tissues, we used a humanized mice model of low-level chronic HIV infection and in which OPN RNA and protein expression was inhibited with targeted aptamers. Interestingly, 4 months after infection when there were no significant differences in HIV viral load in plasma between groups however in contrast, in the spleen, lung, and liver the tissue burden of HIV RNA, as well as the proportion of leukocytes in female and male mice differed depending on whether OPN was expressed or not. The findings collectively demonstrate the potential for complex interactions between host factors like OPN and sex to influence different facets of HIV tissue-level pathogenesis.
Chronic diarrhea poses a significant threat to the health of NHP research colonies, and its primary etiology remains unclear. In macaques, the clinical presentation of intractable diarrhea and weight ...loss that are accompanied by inflammatory infiltrates within the gastrointestinal tract
closely resembles inflammatory bowel disease of humans, dogs, and cats, in which low serum and tissue cobalamin (vitamin B12) levels are due to intestinal malabsorption. We therefore hypothesized that macaques with chronic idiopathic diarrhea (CID) have lower serum cobalamin concentrations
than do healthy macaques. Here we measured serum cobalamin concentrations in both rhesus and pigtailed macaques with CID and compared them with those of healthy controls. Serum cobalamin levels were 2.5-fold lower in pigtailed macaques with CID than control animals but did not differ between
rhesus macaques with CID and their controls. This finding supports the use of serum cobalamin concentration as an adjunct diagnostic tool in pigtailed macaques that present with clinical symptoms of chronic gastrointestinal disease. This use of serum vitamin B12 levels has implications for the future use of parenteral cobalamin supplementation to improve clinical outcomes in this species.
HIV-induced damage to the CNS remains a major challenge for over 30 million people in the world despite the successes of combined antiretroviral therapy in limiting viral replication. Predicting ...development and progression of HIV-associated CNS disease is crucial because prevention and early intervention could be more effective than attempts to promote repair. The SIV/macaque model is the premier platform to study HIV neuropathogenesis, including discovery of predictive factors such as neuroprotective host genes and both blood and CSF biomarkers that precede and predict development of SIV CNS disease. This report details the role of macaque MHC class I genes, longitudinal alterations in biomarkers in the circulation, and expression of inflammatory and neuronal damage markers in CSF using samples from SIV-inoculated pigtailed macaques collected during acute, asymptomatic, and terminal stages of infection.
One of the challenges facing veterinarians and investigators who use rabbits (Oryctolagus cuniculus) as a surgical model in biomedical research is choosing an appropriate and efficacious ...postoperative analgesic without systemic complications and side effects. The objective of
this study was to evaluate the gastrointestinal side effects associated with the postoperative use of buprenorphine in Dutch Belted rabbits. We also evaluated the analgesic meloxicam as an alternative to opioid administration during the postoperative period. Rabbits were assigned to 1 of 3
treatment groups during the postoperative period after routine ovariohysterectomy: buprenorphine (n = 10), meloxicam (n = 10), and incisional infiltration with bupivicaine (no treatment control; n = 10). Feed intake, fecal production, weight loss, urine output, and other physiologic parameters
were monitored and behavior and pain assessments were performed for 7 d after surgery and compared with baseline values collected before surgery. All rabbits showed decreased pellet consumption, fecal production, and weight on day 1 after surgery. This effect was severe in some rabbits that
received bupivicaine; therefore treatment of this entire group with metoclopramide, fluids, and hay was instituted to reverse gut stasis. No significant difference in feed consumption and fecal production was present between the buprenorphine- and meloxicam-treated groups. On the basis of
these results, meloxicam appears to be a suitable alternative or adjunct to buprenorphine for alleviating postoperative pain with minimal risk of anorexia and gastrointestinal ileus.
Peripheral neuropathy is the most frequent neurological complication of HIV infection, affecting more than one-third of infected patients, including patients treated with antiretroviral therapy. ...Although emerging noninvasive techniques for corneal nerve assessments are increasingly being used to diagnose and monitor peripheral neuropathies, corneal nerve alterations have not been characterized in HIV. Here, to determine whether SIV infection leads to corneal nerve fiber loss, we immunostained corneas for the nerve fiber marker βIII tubulin. We developed and applied both manual and automated methods to measure nerves in the corneal subbasal plexus. These counting methods independently indicated significantly lower subbasal corneal nerve fiber density among SIV-infected animals that rapidly progressed to AIDS compared with slow progressors. Concomitant with decreased corneal nerve fiber density, rapid progressors had increased levels of SIV RNA and CD68-positive macrophages and expression of glial fibrillary acidic protein by glial satellite cells in the trigeminal ganglia, the location of the neuronal cell bodies of corneal sensory nerve fibers. In addition, corneal nerve fiber density was directly correlated with epidermal nerve fiber length. These findings indicate that corneal nerve assessment has great potential to diagnose and monitor HIV-induced peripheral neuropathy and to set the stage for introducing noninvasive techniques to measure corneal nerve fiber density in HIV clinical settings.
Thrombocytopenia is common in HIV and SIV infection, and is often associated with disease progression. HIV and SIV-associated thrombocytopenia arise through multiple mechanisms, including decreased ...platelet production, increased platelet destruction due to HIV-mimetic anti-platelet antibodies, and increased use of activated platelets. Activated platelets have the potential to contribute to the pathogenesis of HIV and SIV by interacting directly with inflammatory cells and endothelium and by releasing soluble immunomodulatory cytokines.
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