Annexin-V-DY634 and 7AAD staining.

An article published this year in “OSTEOARTHRITIS AND CARTILAGE” using our annexin-V-DY634 and 7AAD staining, by our customers from Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, and Servicio de Inmunología Hospital Clínico Universitario Lorenzo Blesa, Zaragoza, Spain, in the analysis of how CD56+/CD16- Natural Killer cells expressing the inflammatory protease granzyme A are enriched in synovial fluid from patients with osteoarthritis. Congrats and Thanks.

Summary:

Objective: NK cells have been involved in the pathology of different inflammatory and autoimmune disorders. Inflammation is an important regulator of osteoarthritis (OA), but the molecular and cellular mechanisms regulating this process are not well defined.

Design: To understand the role of NK cells in OA, we have compared the phenotype (CD56 subsets and perforin and granzyme expression) and cytotoxic function of NK cells in peripheral blood and synovial fluid from patients with OA undergoing total knee arthroplasty.

Results: In contrast to peripheral blood lymphocytes, the majority of NK cells from the synovial fluid were CD56brightCD16(-) cells. As expected the expression of the cytolytic mediators perforin and granzyme B in CD56brightCD16(-) cells was low and correlated with a poor cytotoxic potential against K562 sensitive target cells. Surprisingly, this low cytotoxic NK cell subset (but not in peripheral blood) expressed high levels of granzyme A (a protease recently characterized as a key modulator of inflammation in mouse models) in synovial fluid but not in peripheral blood. The presence of the CD56(+)brightCD16(-) cells expressing granzyme A correlated with increased levels of pro-inflammatory cytokines in synovial fluid from OA patients.

Conclusion: Our results indicate that NK cells from the synovium of patients with OA, which present an immunoregulatory non-cytotoxic phenotype, show different phenotype comparing with NK cells from peripheral blood, especially expressing granzyme A, a pro-inflammatory molecule which may contribute to the establishment of chronic articular inflammation in this type of patients.

Reference:

http://www.sciencedirect.com/science/article/pii/S1063458417310555

Product link:

DY634 Annexin V: http://www.immunostep.com/apoptosis-tools/3730-anxvdy-200t.html

7-AAD Staining Solution: http://www.immunostep.com/solutions-buffers-chemicals/2307-7-aad-staining-solution.html