PROBLEM: Natural Killer (NK) cell numbers and cytotoxicity are suppressed during pregnancy. Little is known about postpartum NK number and function. METHOD OF STUDY: Postpartum women (n = 39) were studied at one week and then monthly over the first six postpartum months. The standard natural killer cell cytotoxicity assay (NKCA) was performed. This is a Cr51 release assay from K562 cells cultured with peripheral blood mononuclear cells (PBMCs). RESULTS: Data indicate suppression of NK cytotoxicity in postpartum women. Cytotoxicity at each effector:target (E:T) ratio showed a drop from 1 week postpartum, reaching a nadir at around 2 months, and a trend towards recovery of cytotoxicity from 3 to 6 months. Lytic units (LUs) from pre-incubated cells from postpartum women were lower than age-matched, non-pregnant, non-postpartum controls through the fifth postpartum month. CONCLUSION: These data suggest that the postpartum period, like pregnancy, is characterized by decreased NK cytotoxicity activity. This suppressed NK cytotoxic effect may result as a response to interaction with tolerized fetal microchimeric cells accumulated during pregnancy in maternal blood and tissues.
PROBLEM: Natural Killer (NK) cell numbers and cytotoxicity are suppressed during pregnancy. Little is known about postpartum NK number and function. METHOD OF STUDY: Postpartum women (n = 39) were studied at one week and then monthly over the first six postpartum months. The standard natural killer cell cytotoxicity assay (NKCA) was performed. This is a Cr51 release assay from K562 cells cultured with peripheral blood mononuclear cells (PBMCs). RESULTS: Data indicate suppression of NK cytotoxicity in postpartum women. Cytotoxicity at each effector:target (E:T) ratio showed a drop from 1 week postpartum, reaching a nadir at around 2 months, and a trend towards recovery of cytotoxicity from 3 to 6 months. Lytic units (LUs) from pre-incubated cells from postpartum women were lower than age-matched, non-pregnant, non-postpartum controls through the fifth postpartum month. CONCLUSION: These data suggest that the postpartum period, like pregnancy, is characterized by decreased NK cytotoxicity activity. This suppressed NK cytotoxic effect may result as a response to interaction with tolerized fetal microchimeric cells accumulated during pregnancy in maternal blood and tissues.
Authors: M Ponte; C Cantoni; R Biassoni; A Tradori-Cappai; G Bentivoglio; C Vitale; S Bertone; A Moretta; L Moretta; M C Mingari Journal: Proc Natl Acad Sci U S A Date: 1999-05-11 Impact factor: 11.205
Authors: Nelly R Mugo; Renee Heffron; Deborah Donnell; Anna Wald; Edwin O Were; Helen Rees; Connie Celum; James N Kiarie; Craig R Cohen; Kayitesi Kayintekore; Jared M Baeten Journal: AIDS Date: 2011-09-24 Impact factor: 4.177