5,463 research outputs found
Human mesenchymal stem cells affect IgG production induced by lipopolysaccharide, cytomegalovirus and varicella zoster virus in human spleen cells
Coherent state triplets and their inner products
It is shown that if H is a Hilbert space for a representation of a group G,
then there are triplets of spaces F_H, H, F^H, in which F^H is a space of
coherent state or vector coherent state wave functions and F_H is its dual
relative to a conveniently defined measure. It is shown also that there is a
sequence of maps F_H -> H -> F^H which facilitates the construction of the
corresponding inner products. After completion if necessary, the F_H, H, and
F^H, become isomorphic Hilbert spaces. It is shown that the inner product for H
is often easier to evaluate in F_H than F^H. Thus, we obtain integral
expressions for the inner products of coherent state and vector coherent state
representations. These expressions are equivalent to the algebraic expressions
of K-matrix theory, but they are frequently more efficient to apply. The
construction is illustrated by many examples.Comment: 33 pages, RevTex (Latex2.09) This paper is withdrawn because it
contained errors that are being correcte
Mesenchymal Stromal Cells Engage Complement and Complement Receptor Bearing Innate Effector Cells to Modulate Immune Responses
Infusion of human third-party mesenchymal stromal cells (MSCs) appears to be a promising therapy for acute graft-versus-host disease (aGvHD). To date, little is known about how MSCs interact with the body's innate immune system after clinical infusion. This study shows, that exposure of MSCs to blood type ABO-matched human blood activates the complement system, which triggers complement-mediated lymphoid and myeloid effector cell activation in blood. We found deposition of complement component C3-derived fragments iC3b and C3dg on MSCs and fluid-phase generation of the chemotactic anaphylatoxins C3a and C5a. MSCs bound low amounts of immunoglobulins and lacked expression of complement regulatory proteins MCP (CD46) and DAF (CD55), but were protected from complement lysis via expression of protectin (CD59). Cell-surface-opsonization and anaphylatoxin-formation triggered complement receptor 3 (CD11b/CD18)-mediated effector cell activation in blood. The complement-activating properties of individual MSCs were furthermore correlated with their potency to inhibit PBMC-proliferation in vitro, and both effector cell activation and the immunosuppressive effect could be blocked either by using complement inhibitor Compstatin or by depletion of CD14/CD11b-high myeloid effector cells from mixed lymphocyte reactions. Our study demonstrates for the first time a major role of the complement system in governing the immunomodulatory activity of MSCs and elucidates how complement activation mediates the interaction with other immune cells
New perspective on the U(n) Wigner-Racah calculus. I. Vector coherent state theory and construction of Gel'fand bases
Using a vector coherent state theory, it is shown that the construction of Gel'fand bases for the unitary group is particularly simple. The very specific rules for construction of the states greatly facilitate the subsequent computation of matrix elements of the generators of the u(n) Lie algebra.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48816/2/jav20i9p2241.pd
Dynamic Changes in Brain Mesenchymal Perivascular Cells Associate with Multiple Sclerosis Disease Duration, Active Inflammation, and Demyelination
Vascular changes, including blood brain barrier destabilization, are common pathological features in multiple sclerosis (MS) lesions. Blood vessels within adult organs are reported to harbor mesenchymal stromal cells (MSCs) with phenotypical and functional characteristics similar to pericytes. We performed an immunohistochemical study of MSCs/pericytes in brain tissue from MS and healthy persons. Post-mortem brain tissue from patients with early progressive MS (EPMS), late stage progressive MS (LPMS), and healthy persons were analyzed for the MSC and pericyte markers CD146, platelet-derived growth factor receptor beta (PDGFRβ), CD73, CD271, alpha-smooth muscle actin, and Ki67. The MS samples included active, chronic active, chronic inactive lesions, and normal-appearing white matter. MSC and pericyte marker localization were detected in association with blood vessels, including subendothelial CD146+PDGFRβ+Ki67+ cells and CD73+CD271+PDGFRβ+Ki67– cells within the adventitia and perivascular areas. Both immunostained cell subpopulations were termed mesenchymal perivascular cells (MPCs). Quantitative analyses of immunostainings showed active lesions containing increased regions of CD146+PDGFRβ+Ki67+ and CD73+CD271+PDGFRβ+Ki67– MPC subpopulations compared to inactive lesions. Chronic lesions presented with decreased levels of CD146+PDGFRβ+Ki67+ MPC cells compared to control tissue. Furthermore, LPMS lesions displayed increased numbers of blood vessels harboring greatly enlarged CD73+CD271+ adventitial and perivascular areas compared to control and EPMS tissue. In conclusion, we demonstrate the presence of MPC subgroups in control human brain vasculature, and their phenotypic changes in MS brain, which correlated with inflammation, demyelination and MS disease duration. Our findings demonstrate that brain-derived MPCs respond to pathologic mechanisms involved in MS disease progression and suggest that vessel-targeted therapeutics may benefit patients with progressive MS
Mesenchymal stromal cells enhance the engraftment of hematopoietic stem cells in an autologous mouse transplantation model
2.5 Mesenchymal Stem Cell Therapy has significant clinical effect in proteoglycan induced arthritis
Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
We describe the results of an extremely deep, 0.28 deg^2 survey for z = 3.1
Ly-alpha emission-line galaxies in the Extended Chandra Deep Field South. By
using a narrow-band 5000 Anstrom filter and complementary broadband photometry
from the MUSYC survey, we identify a statistically complete sample of 162
galaxies with monochromatic fluxes brighter than 1.5 x 10^-17 ergs cm^-2 s^-1
and observers frame equivalent widths greater than 80 Angstroms. We show that
the equivalent width distribution of these objects follows an exponential with
a rest-frame scale length of w_0 = 76 +/- 10 Angstroms. In addition, we show
that in the emission line, the luminosity function of Ly-alpha galaxies has a
faint-end power-law slope of alpha = -1.49 +/- 0.4, a bright-end cutoff of log
L^* = 42.64 +/- 0.2, and a space density above our detection thresholds of 1.46
+/- 0.12 x 10^-3 h70^3 galaxies Mpc^-3. Finally, by comparing the emission-line
and continuum properties of the LAEs, we show that the star-formation rates
derived from Ly-alpha are ~3 times lower than those inferred from the
rest-frame UV continuum. We use this offset to deduce the existence of a small
amount of internal extinction within the host galaxies. This extinction,
coupled with the lack of extremely-high equivalent width emitters, argues that
these galaxies are not primordial Pop III objects, though they are young and
relatively chemically unevolved.Comment: 45 pages, 15 figures, accepted for publication in the Astrophysical
Journa
Treatment with granulocyte colony-stimulating factor after allogeneic bone marrow transplantation for acute leukemia increases the risk of graft-versus-host disease and death
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