Cord blood Vα24-Vß11 natural killer T cells display a Th2-chemokine receptor profile and cytokine responses.

BACKGROUND: The fetal immune system is characterized by a Th2 bias but it is unclear how the Th2 predominance is established. Natural killer T (NKT) cells are a rare subset of T cells with immune regulatory functions and are already activated in utero. To test the hypothesis that NKT cells are part of the regulatory network that sets the fetal Th2 predominance, percentages of Vα24(+)Vß11(+) NKT cells expressing Th1/Th2-related chemokine receptors (CKR) were assessed in cord blood. Furthermore, IL-4 and IFN-γ secreting NKT cells were quantified within the single CKR(+) subsets. RESULTS: Cord blood NKT cells expressed the Th2-related CCR4 and CCR8 at significantly higher frequencies compared to peripheral blood NKT cells from adults, while CXCR3(+) and CCR5(+) cord blood NKT cells (Th1-related) were present at lower percentages. Within CD4(neg)CD8(neg) (DN) NKT cells, the frequency of IL-4 producing NKT cells was significantly higher in cord blood, while frequencies of IFN-γ secreting DN NKT cells tended to be lower. A further subanalysis showed that the higher percentage of IL-4 secreting DN NKT cells was restricted to CCR3(+), CCR4(+), CCR5(+), CCR6(+), CCR7(+), CCR8(+) and CXCR4(+) DN subsets in cord blood. This resulted in significantly decreased IFN-γ /IL-4 ratios of CCR3(+), CCR6(+) and CCR8(+) cord blood DN NKT cells. Sequencing of VA24AJ18 T cell receptor (TCR) transcripts in sorted cord blood Vα24Vß11 cells confirmed the invariant TCR alpha-chain ruling out the possibility that these cells represent an unusual subset of conventional T cells. CONCLUSIONS: Despite the heterogeneity of cord blood NKT cells, we observed a clear Th2-bias at the phenotypic and functional level which was mainly found in the DN subset. Therefore, we speculate that NKT cells are important for the initiation and control of the fetal Th2 environment which is needed to maintain tolerance towards self-antigens as well as non-inherited maternal antigens.

Texas certified volunteer Long-Term Care Ombudsmen: perspectives of role and effectiveness.

BACKGROUND: Under the federally mandated Long-Term Care Ombudsman Program (LTCOP), certified volunteer ombudsmen (CVO) advocate for the welfare and rights of residents in nursing facilities. In Texas, the Department on Aging contracts with 28 agencies to deliver the LTCOP in respective regions. Regional ombudsman staff in charge of a group of CVOs administers each local program. The volunteer ombudsman role is threefold: advocate, mediator, and friendly visitor. METHODS: This descriptive study used a 75-item mail survey designed to gain a better understanding of CVOs' perspectives of their role and effectiveness. A total of 361 active, certified volunteers participated, representing all of the 28 regional Texas ombudsman programs. A series of focus groups was used to amplify survey data. RESULTS: Findings indicate overall role satisfaction, although perception of satisfaction varied with volunteers' age, length of service, level of education, and work experience. Volunteers felt most effective in promoting residents' rights and welfare, and least effective in dealing with financial exploitation, nutrition, and hydration issues. Although not always able to achieve desired changes, most volunteers believed that the ombudsman presence was a positive force. A need for improved understanding and support of the ombudsman role among facility staff and regulatory agents was exposed. DISCUSSION: CVOs' potentially favorable impact on the institutional setting in general, and facility personnel in particular, is dependent on the support from state personnel and regional ombudsman staff as well as the willingness of nursing facility staff to cooperate. Volunteers' sense of performance effectiveness is essential to the success of the LTCOP. Specific recommendations based on study findings are intended to assist in assuring continuous program quality improvement purposed to ensure residents' quality of life.