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Antigen-specific hyporesponsiveness to filarial antigens is a phenomenon observed in patent infection with lymph-dwelling filarial parasites of humans. This phenomenon has been attributed to a multitude of factors, one of which is altered monocyte function. To examine the role played by monocytes in filarial infection, we assessed the responses of monocytes obtained from normal and filarial parasite-infected individuals to both crude filarial antigen and purified recombinant filarial antigen WbSXP-1 and attempted to relate these to the altered lymphoproliferative responses seen in filarial infection. Monocytes from microfilaremic (MF) patients demonstrated an inability to respond to lipopolysaccharide compared to monocytes from endemic normal persons or from lymphedema patients. Indeed, interleukin 1␤ (IL-1␤) production was severely limited, a finding that did not extend to monocyte responses to filarial antigens. Serum from MF patients reduced adherence and spreading of normal monocytes, a finding not seen with serum from the other clinical groups. Interestingly, there was a significant correlation between the production of IL-1␤ and adherence. Moreover, the levels of spontaneous production of IL-1␤ correlated with high levels of spontaneous secretion of IL-10. The effects observed were not a result of diminished viability or alteration in the expression of the cell surface markers CD14 and HLA-DR. These data suggest that monocyte function is dampened in MF patients, a finding which could alter lymphoproliferative responses during patent infection.Understanding the induction of differentiated T-cell responses in helminth infections has been a major goal for parasite immunologists. The source of cytokines involved in the skewing of T-cell responses in helminth infections has been of particular interest, as the cytokine microenvironment is considered to be the most important factor influencing the differentiation of naive T cells and the generation of immunoregulatory cells (1,30,31,36,37). Among individuals with human lymphatic filariasis, those with patent infection (microfilaremic or antigenemic) exhibit parasite antigen-specific down-regulation of T-cell proliferation and gamma interferon production. These responses are different from those in patients with lymphedema/elephantiasis (mixed Th1/Th2 response) and infection-free endemic normal (EN) persons (predominant Th1 response to parasite antigen). The occurrence of filarial parasite-associated modulation of the immune response in microfilaremic patients is supported by extensive clinical (35,38,41) and animal (27) data. To date, however, no single mechanism can explain the modulatory effects of filarial infection in patients with patent infection.The induction and maintenance of Th2-type immune responses are based largely on studies with murine models showing that antigen affinity for the T-cell receptor (6), the dose or route by which antigen is administered (11,14), costimulatory molecule interactions (32, 49), the prevailing in vivo cytokine milieu (45),...

Electrolyte membranes play a critical role as their properties directly influences the performance of fuel cell. A copper-based metal organic framework (MOF) anchored polymeric blend membrane was developed for fuel cell application. Cu-MOF serves as an excellent filler material due to its small size, high degree of crystallinity and surface area. Through XRD analysis well defined crystallite sites was evidenced and the average crystallite size measured ∼ 0.3 Å. The acidic functional group in MOF interacts with sulfonic acid (À SO 3 H) group in sulfonated polyetheretherketone (sPEEK) matrix which further improves proton conduction via. hydrogen bonding interaction. With the as-prepared sPEEK as the matrix; polyimide (PI) was blended to improve its processibility and thermal stability. Cu-MOF loaded composite membranes (X wt.% Cu-MOF-sPEEK/PI) were prepared and characterized. To assess the suitability of the developed membranes for proton exchange membrane fuel cell (PEMFC) applications, ion exchange capacity (IEC), water uptake and proton conductivity was measured. 3 wt.% Cu-MOF-2-sPEEK/PI membrane displayed an IEC value of 2.35 meq g À 1 with a water uptake of 38.18 % and proton conductivity of 0.0711 S cm À 1 . Overall, the experimental results of the prepared membranes revealed that they act as an efficient proton exchange membrane (PEM) for PEMFCs.

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