Decreased bone mineral density in experimental myasthenia gravis in C57BL/6 mice.

Experimental autoimmune myasthenia gravis (EAMG), an animal model of myasthenia gravis (MG), can be induced in C57BL/6 (B6, H-2 b) mice by 2-3 injections with Torpedo californica AChR (tAChR) in complete Freund's adjuvant. Some EAMG mice exhibit weight loss with muscle weakness. The loss in body weight, which is closely associated with bone structure, is particularly evident in EAMG mice with severe muscle weakness. However, the relationship between muscle weakness and bone loss in EAMG has not been studied before. Recent investigations on bone have shed light on association of bone health and immunological states. It is possible that muscle weakness in EAMG developed by anti-tAChR immune responses might accompany bone loss. We determined whether reduced muscle strength associates with decreased bone mineral density (BMD) in EAMG mice. EAMG was induced by two injections at 4-week interval of tAChR and adjuvants in two different age groups. The first tAChR injection was either at age 8 weeks or at 15 weeks. We measured BMD at three skeletal sites, including femur, tibia, and lumbar vertebrae, using dual energy X-ray absorptiometry. Among these bone areas, femur of EAMG mice in both age groups showed a significant decrease in BMD compared to control adjuvant-injected and to non-immunized mice. Reduction in BMD in induced EAMG at a later-age appears to parallel the severity of the disease. The results indicate that anti-tAChR autoimmune response alone can reduce bone density in EAMG mice. BMD reduction was also observed in adjuvant-injected mice in comparison to normal un-injected mice, suggesting that BMD decrease can occur even when muscle activity is normal. Decreased BMD observed in both tAChR-injected and adjuvant-injected mice groups were discussed in relation to innate immunity and bone-related immunology involving activated T cells and tumour necrosis factor-related cytokines that trigger osteoclastogenesis and bone loss.

ASIA or Shoenfeld's syndrome--an autoimmune syndrome induced by adjuvants.

Recently, reports have suggested grouping different autoimmune conditions that are triggered by external stimuli as a single syndrome called autoimmune syndrome induced by adjuvants (ASIA). This syndrome is characterized by the appearance of myalgia, myositis, muscle weakness, arthralgia, arthritis, chronic fatigue, sleep disturbances, cognitive impairment and memory loss, and the possible emergence of a demyelinating autoimmune disease caused by systemic exposure after vaccines and adjuvants. As there are no markers for ASIA, the authors intend to present ASIA, or Shoenfeld's syndrome, as an autoimmune syndrome induced by adjuvants.

Test-retest-reliability and validity of the Kinesiology muscle test.

OBJECTIVES: To assess the test-retest-reliability and validity of the Health Kinesiology muscle test. PATIENTS: Seven patients with clinically and allergologically confirmed wasp venom allergy. DESIGN: Four Health Kinesiology-examiners tested each patient in a random order for 10 verum and 10 placebo bottles. All examiners used the anterior deltoid as indicator muscle. Patients and examiners were completely blinded. OUTCOME MEASURES: Weak muscle holds were rated as 'sensitivity' towards the test substance, stable holding as normal (not sensitive). RESULTS: An overall kappa of 0.03 (95%-CI: -0.02-0.07) indicates the test is not reliable. Individual kappas do not substantially vary from examiner to examiner. Sensitivity and specificity were estimated at 40% and 60%. CONCLUSIONS: The results suggest that the use of Health Kinesiology as a diagnostic tool is not more useful than random guessing. This should at least be true in patients with insect venom allergy that are tested by examiners with average skills.