No abstract

The recruitment of lymphocytes across the blood brain barrier (BBB) is mediated by adhesion molecules and chemokines. The expression of activation markers and of chemokine receptors on T cells homing to the nervous system (NS) may help define their functional state. In the cerebrospinal fluid (CSF) of subjects with inflammatory neurological diseases (IND), including multiple sclerosis, we observed an increased number of T cells coexpressing CXCR3 and CCR5 as well as T cells with a CD45RO+ CCR7+ CD27+ memory phenotype. A subset of CCR7+ T cells coexpressed CXCR3 and CCR5. We also detected an increased number of interferon-gamma-producing T cells in the CSF compared with peripheral blood, mostly but not exclusively in the CD45RO+ CCR7- CD27- compartment. T helper 1 (Th1) clones, established from the CSF of individuals with IND and from a healthy subject, similarly migrated to CXCL10, CXCL12, and CCL5. CXCL10, CXCL12, and CCL19 were increased in the CSF of individuals with neuroinflammation. These findings suggest that CSF is enriched in Th1-polarized memory T cells capable of differentiating into effector cells upon antigen encounter. These cells are recruited into the CSF by inducible chemokines. Thus, CSF represents a transitional station for T cells trafficking to and from the NS.

T-lymphocytes with T-cell antigen receptor (TCR) comprising a gamma chain and a delta chain (gamma delta+ T cells) are believed to be involved in the immune reaction to mycobacterial antigens, and they have been found in increased proportions in sarcoid patients. We evaluated the proportions of gamma delta+ T-lymphocytes and of two major gamma delta+ subpopulations, the V delta 1+ and the V delta 2+ T-cell subsets, in 10 normal blood donors, in 15 patients with tuberculosis (TB), seven of whom had pleural effusion (PE), and in 12 patients with pulmonary sarcoidosis (PS), nine of whom underwent bronchoalveolar lavage (BAL). T-cell subsets were evaluated in peripheral blood (PBL) of all subjects and in PE from patients with TB and in BAL from patients with PS. Compared with normal blood donors, patients with TB had increased proportions of PBL CD3+ gamma delta+ T cells (6 +/- 1% versus 14 +/- 3% of CD3+ T cells, p < 0.05) because of the presence of four patients who had an increase (respectively, 18.3, 22.0, 24.2, and 35.4% of CD3+ T cells) of gamma delta+ T cells. In patients with TB and PE, gamma delta+ T cells were 7.9 +/- 2.7%, a value not different from that in the tubercular PBL and in normal PBL. Although patients with PS had proportions of PBL gamma delta+ T cells (9.2 +/- 3.4%) similar to those in normal PBL, two patients had increased (35 and 31%) PBL gamma delta+ T-lymphocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Abstract-Myoelectric prostheses are successfully controlled using muscle electrical activity, thereby restoring lost motor functions. However, the somatosensory feedback from the prosthesis to the user is still missing. The sensory substitution methods described in the literature comprise mostly simple position and force sensors combined with discrete stimulation units. The present study describes a novel system for sophisticated electrotactile feedback integrating advanced distributed sensing (electronic skin) and stimulation (matrix electrodes). The system was tested in eight healthy subjects who were asked to recognize the shape, trajectory and direction of a set of dynamic movement patterns (single lines, geometrical objects, letters) presented on the electronic skin. The experiments demonstrated that the system successfully translated the mechanical interaction into the moving electrotactile profiles, which the subjects could recognize with a good performance (shape recognition: 86±8% lines, 73±13% geometries, 72±12% letters). In particular, the subjects could identify the movement direction with a high confidence. These results are in accordance with previous studies investigating the recognition of moving stimuli in human subjects. This is an important development towards closed-loop prostheses providing comprehensive and sophisticated tactile feedback to the user, facilitating the control and the embodiment of the artificial device into the user body scheme.