Diagnostic exercise: papulovesicular dermatitis in rhesus macaques (Macaca mulatta)

Eleven rhesus monkeys developed multifocal erythematous and a vesicular rash. Most recovered spontaneously, but a 21-year-old female became moribund and was euthanized. Findings were of vesicular dermatitis and widespread multifocal hemorrhagic necrosis of the lungs and other viscera, with intralesional intranuclear inclusions. Simian varicella virus was identified as the cause by polymerase chain reaction analysis and serologic testing.

Gender is a major factor in determining the severity of mycoplasma respiratory disease in mice

Gender is a significant factor in determining the susceptibility to and severity of pulmonary diseases in both humans and animals. Murine respiratory mycoplasmosis (MRM), due to Mycoplasma pulmonis infection, is an excellent animal model for evaluation of the role of various host factors on the development of acute or chronic inflammatory lung diseases. MRM has many similarities to mycoplasma respiratory disease in humans. The purpose of the present study was to determine whether gender has a significant impact on lung disease due to M. pulmonis infection in mice. It was demonstrated that male mice consistently developed more severe disease in the lung parenchyma than did female mice. There was no gender difference in disease severity along the airways or any difference in mycoplasma numbers in lungs of male and female mice. Furthermore, surgical removal of reproductive organs reduced the severity of mycoplasma disease and the numbers of mycoplasma organisms recovered from lungs. Thus, gender plays a significant role in determining the severity of M. pulmonis disease. In fact, the gender of the host was a major factor in determining whether an acute or chronic inflammatory lung disease developed after infection with M. pulmonis.

Iridodialysis in a rhesus macaque: a case report

During routine physical examination, a five-year-old male rhesus macaque (Macaca mulatta) was observed to have gaps in the right iris. Ophthalmic examination revealed inferior and superior iridodialysis with an anterior cortical cataract. The optic nerve head and fundus were normal. Uninvolved areas of the iris and anterior-chamber angle were normal on the basis of results of gonioscopy. Tonometry revealed normal intraocular pressure. The cause of the iridodialysis in this monkey's eye was not known. The animal had been housed individually since arrival due to requirements of the research protocol. Although the concomitant cataract supports a traumatic cause, there was no history of cranial or other ocular injuries. Trauma from fighting through the cage walls, self-trauma or falling inside the cage while under sedation cannot be ruled out. Multiple hematologic evaluations disclosed no abnormalities. This animal did not manifest behavioral abnormalities or any indication of pain. Therefore, treatment was not initiated. Intraocular pressure continues to be monitored at least semiannually.

The safety of OP-1 for lumbar fusion with decompression-- a canine study

OBJECTIVE

Bone morphogenetic proteins can serve as adjuncts to autologous bone to achieve bony fusion, and recombinant BMPs such as osteogenic protein-1 (OP-1) have the potential to replace autologous bone altogether as fusion substrate. However, relatively little is known about the safety of OP-1 for spinal fusion procedures. This study examined the effects of OP-1 intentionally placed in the subarachnoid space following thecal sac decompression, and used as graft substrate in a canine dorsolateral lumbar spine fusion model.

METHODS

Lumbar decompression with dorsolateral fusion was performed on 30 canines. The dura was opened to simulate an intraoperative rent and OP-1 was placed in the subarachnoid space and in the fusion bed. Animals were sacrificed after 16 weeks and the spines were examined manually, radiographically and pathologically.

RESULTS

All animals treated with OP-1 developed new bone in the subarachnoid space. This bone compressed the spinal cord, but no clinical or pathological features of neurotoxicity were noted. Mild spinal stenosis was noted at the site of dural decompression in the OP-1 treated animals. Over 80% of animals treated with OP-1 developed fusion as assessed by palpation (52% by CT criteria), while only 25% of control animals fused.

CONCLUSIONS

Recombinant human OP-1 is effective at promoting fusion in a canine dorsolateral lumbar spine fusion model. However, bone growth can occur over exposed, decompressed dura, and it can form in the subdural and subarachnoid spaces. The use of OP-1 as an adjunct to spinal fusion appears to have merit, but its use must be carefully controlled to avoid unwanted bone formation and subsequent neural compression.

Roles of innate and adaptive immunity in respiratory mycoplasmosis

Current evidence suggests that host defense in respiratory mycoplasmosis is dependent on both innate and humoral immunity. To further delineate the roles of innate and adaptive immunity in antimycoplasmal defenses, we intranasally infected C3H/HeSnJ-scid/scid (C3H-SCID), C3H/HeSnJ (C3H), C57BL/6J-scid/scid (C57-SCID), and C57BL/6N (C57BL) mice with Mycoplasma pulmonis and at 14 and 21 days postinfection performed quantitative cultures of lungs and spleens, quantification of lung lesions, and histopathologic assessments of all other major organs. We found that numbers of mycoplasmas in lungs were associated with genetic background (C3H susceptible, C57BL resistant) rather than functional state of adaptive immunity, indicating that innate immunity is the main contributor to antimycoplasmal defense of the lungs. Extrapulmonary dissemination of mycoplasmas with colonization of spleens and histologic lesions in multiple organs was a common occurrence in all mice. The absence of adaptive immune responses in severe combined immunodeficient (SCID) mice resulted in increased mycoplasmal colonization of spleens and lesions in extrapulmonary sites, particularly spleens, hearts, and joints, and also reduced lung lesion severity. The transfer of anti-M. pulmonis serum to infected C3H-SCID mice prevented extrapulmonary infection and disease, while the severity of lung lesions was restored by transfer of naive spleen cells to infected C3H-SCID mice. Collectively, our results strongly support the conclusions that innate immunity provides antimycoplasmal defense of the lungs and humoral immunity has the major role in defense against systemic dissemination of mycoplasmal infection, but cellular immune responses may be important in exacerbation of mycoplasmal lung disease.

Resistance to mycoplasmal lung disease in mice is a complex genetic trait

Mouse strains differ markedly in resistance to Mycoplasma pulmonis infection, and investigation of these differences holds much promise for understanding the mechanisms of antimycoplasmal host defenses. To determine the potential genetic diversity of resistance to disease in murine respiratory mycoplasmosis (MRM) and to select disease-resistant and nonresistant mouse strains for further genetic analysis, we screened 17 inbred mouse strains of various Bcg and H-2 genotypes for resistance to M. pulmonis. Mice were inoculated intranasally with 10(4) CFU of M. pulmonis UAB CT and evaluated at 21 days postinfection for severities of the four histologic lung lesions characteristic of MRM: alveolar exudate, airway exudate, airway epithelial hyperplasia, and lymphoid infiltrate. On the basis of these assessments of MRM severity, one group of mouse strains was found to be extremely resistant to disease (C57BR/cdJ, C57BL/6NCr, C57BL/10ScNCr, and C57BL/6J). The remaining strains of mice (C57L/J, SJL/NCr, BALB/cAnNCr, A/JCr, C3H/HeJ, SWR/J, AKR/NCr, CBA/NCr, C58/J, DBA/2NCr, C3H/HeNCr, C3HeB/FeJ, and C3H/HeJCr) developed disease of widely varying severities. Furthermore, strains in the group with more disease varied in pattern of lesion severity. While the severities of all four lesions were correlated in most mouse strains, this was not always true. DBA/2NCr mice had one of the highest scores for alveolar exudate, only a moderate score for airway exudate, and significantly lower scores for both airway epithelial hyperplasia and lymphoid infiltrate than all other strains susceptible to lung disease. DBA/2NCr mice had one of the highest mortality rates. We concluded that resistance to MRM is a complex trait. The observed differences in lung disease severity could not be explained by known differences at the Bcg or H-2 locus in the strains of mice we studied.

Chronic respiratory mycoplasmosis in C3H/HeN and C57BL/6N mice: lesion severity and antibody response

Mycoplasma pneumoniae is a leading, worldwide cause of death and disability due to pneumonia. Mycoplasma pulmonis infection in mice is an invaluable model for the study of host defenses against respiratory mycoplasmas in vivo. C3H/HeN mice are much more susceptible to acute inflammatory lung disease due to M. pulmonis than C57BL/6N mice, but little is known about the chronic disease in these mouse strains. We infected C3H/HeN and C57BL/6N mice with 10(4) CFU of M. pulmonis UAB CT and evaluated them at weekly intervals by quantitative mycoplasma culture of nasal passages, trachea, and lungs, assessment of lesion severity in nasal passages, trachea, and lungs, and determination of serum immunoglobulin classes and subclasses by enzyme-linked immunosorbent assay. We found that C3H/HeN mice had 2 to 5 logs more organisms in their lungs and far more severe lung disease than C57BL/6N mice through 63 days postinfection. Although both strains of mice developed the same classes of antibody, C3H/HeN mice had much greater anti-M. pulmonis immunoglobulin G (IgG) responses in the IgG1 and IgG2a subclasses than C57BL/6N mice. These results suggest that adaptive immunity does not effect resolution of chronic mycoplasma infection and disease in the lungs.