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Background: Cynomolgus monkeys (Macaca fascicularis) are widely used animal models in biomedical research. However, the phenotypic characteristics of cynomolgus monkey (CM) B cells in peripheral blood (PB) and lymphoid organs are poorly understood. Methods: FACS analyses of PB-, spleen-, lymph node (LN)-, and bone marrow (BM)-derived B cells were performed. Results: CM peripheral blood B cells have a smaller fraction of CD27Ϫ (naive) cells (ϳ40%), as compared to human blood samples (ϳ70%). Similar to humans, an early activation marker, CD23, is expressed more on CD27

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Natural killing (NK) by peripheral blood mono‐nuclear cells (PBMC) against K562 cells was examined in 27 patients with Sjögren's syndrome and 17 normal controls. NK activity in the patients was significantly reduced compared with normal controls (34.6 ± 3.4% versus 52.2 ± 3.4%, P < 0.001). Patients with secondary Sjögren's had lower cytotoxicity compared with those who had primary Sjögren's (28.5 ± 5.5% versus 37.3 ± 4.2%, P < 0.01). The proportion of PBMC with characteristics of NK cells was not decreased in the patients. NK by normal PBMC was diminished both in the presence of sera from patients with reduced NK and when the effector cells were pretreated with the sera. Pretreatment of target K562 cells did not alter NK activity. Suppression of NK by sera from patients did not correlate with levels of immune complexes or with antilymphocyte antibodies. Some patients had adherent cells which inhibited NK function. Addition of either indomethacin or catalase partially restored NK activity in such patients, indicating that both prostaglandins and hydrogen peroxide play a role in suppression. These data suggest that multiple mechanisms are involved in the defective NK activity seen in patients with Sjögren's syndrome. The reduction of NK activity in Sjögren's syndrome may contribute to the increased incidence of lymphoid malignancy.

The development of vaccines to prevent infectious diseases has been one of the most important contributions of biomedical sciences. Increasing understanding in biochemistry, molecular biology, molecular genetics and related fields have provided an opportunity for the development of new generation vaccines that are based on rational design approaches. This is possible because of proper understanding of the microbial-genetics, biochemistry, host-pathogen interaction and recent developments in molecular immunology. Another important improvement made in the quality of vaccine production is the incorporation of immunomodulators or adjuvants with modified delivery vehicles viz liposomes, Iscoms and microspheres apart from alum being used as a gold standard. This article reviews the art of vaccination from Jenner period to present day context highlighting all the developments made at each stage of the vaccine development. Various cdteda have been discussed regarding the selection of epitopes that expand B & T cells, its linkage with other accessory cells of the immune system, means to overcome MHC linked immune unresponsiveness, enhanced antigen processing and presentations that specially induce either helper or cytotoxic or mucosal immune responses were critically discussed.