Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024312 (lymphopenia)
 4,859 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inflammatory cells in lymph nodes of eighteen patients suffering from culture-proven tuberculous lymphadenitis were examined by histological and immunohistochemical techniques. Ten patients suffered from symptomatic HIV-infection and eight patients were immunocompetent individuals without HIV-1 serology. Characteristic granulomas with or without caseation were observed in eight immunocompetent and four HIV-1-infected patients with less marked lymphopenia of CD4 positive peripheral blood lymphocytes. No epitheloid cell formation was present in lymph nodes of HIV1-infected patients with more severe depression of CD4 positive peripheral blood lymphocyte count. Foamy macrophages were found instead of these cells. While many cells--predominantly lymphocytes--express CD25 (IL-2 receptor) in cases with typical epitheloid granulomas there is no such CD25 expression in cases without any epitheloid cell formation. This result suggest that T cell function is necessary for epitheloid granuloma formation in human tuberculosis. The phenotype of macrophages underwent progressive changes parallel to decreasing numbers of CD4 positive peripheral blood lymphocytes. Foamy macrophages in Mycobacterium avium-intracellulare infection represented an end-stage phenotype. They were positive for S100 protein and they did not express lysozyme, alpha-1-anti-chymotrypsin, L1 antigen (Mac387) and CD4, whereas positivity for HLA-DR, CD68 and Ki-M8 was preserved. In situ immunohistochemical demonstration of IFN-alpha, IFN-beta, TNF-alpha, IL-1 and IL-6 revealed that foamy cells in M. tuberculosis infection were highly active effector cells. They contained higher concentrations of the examined cytokines than epitheloid cells in the lesions of HIV+ and HIV-patients. Corresponding to these findings the histological proof of acid-fast bacilli was generally not successful in typical HIV-associated tuberculosis. The foamy appearance may result from the lipid-rich cell membranes of destroyed acid-fast bacilli. In contrast acid-fast bacilli-packed foamy macrophages in AIDS patients with M. avium-intracellulare (MAI) infection did not produce any of the examined cytokines.
 ...
PMID:Immunohistochemical analysis of cell composition and in situ cytokine expression in HIV- and non-HIV-associated tuberculous lymphadenitis. 771 49

Type I interferons (IFN), including IFN-alpha and IFN-beta, cause severe lymphopenia, resulting from altered lymphocyte recirculation and redistribution. IFN-tau, a product of trophectoderm of ruminant conceptuses and new member of the type I IFN family has not been examined for its effect on leukocyte recirculation. Additionally, differential effects of type I IFNs on the redistribution and recirculation of subsets of T cells have not been reported. The present study determined the effects of IFN-tau on the redistribution and recirculation of ovine leukocytes and T cell subsets. Total peripheral blood leukocytes, lymphocytes, and segmented neutrophils were reduced (p < 0.05) following treatment of lambs with IFN-tau. Furthermore, administration of IFN-tau caused an acute, differential reduction in peripheral blood CD4+ T cells (p < 0.05), CD5+ cells (p < 0.05), and gammadelta TCR+ (p < 0.01) T cells but had no effect on CD8+ T cells (p > 0.05). IFN-tau reduced the percentage of gammadelta T cells by 8-fold and that of CD4+ T cells and CD5+ cells by <2-fold in peripheral blood when compared with control lambs. The reduction in leukocytes, lymphocytes, and neutrophils was observed as early as 6-12 h after administration of IFN-tau, but levels returned to control values within 48 h. These results indicate that IFN-tau, like other members of the type I IFN family, can have immediate effects on leukocyte recirculation and redistribution. The present study is the first to demonstrate that IFN-tau differentially regulates T cell recirculation with the greatest effect on gammadelta TcR+ T cells.
 ...
PMID:Trophoblast IFN-tau differentially induces lymphopenia and neutropenia in lambs. 978 12

Combination therapy may benefit the subgroup of patients with secondary progressive multiple sclerosis (SPMS) who do not respond to interferon beta (IFNB). We performed a two-year study of azathioprine (AZA) combined with IFNB-1b in SPMS patients who had not responded well to IFNB-1b alone. Patients with SPMS were eligible for this non-controlled prospective study if they had two or more relapses requiring corticosteroid treatment or deteriorated by at least 0.5 points on the Expanded Disability Status Scale (EDSS) while on IFNB-1b in the year preceeding the study. Patients were to continue treatment with IFNB-1b (8 MIU qod, subcutaneous) and received AZA (50 mg tid, oral). Safety was assessed in terms of adverse reactions and laboratory measures graded according to the WHO toxicity scale. Efficacy was explored by changes in relapse rate, EDSS, 9-hole peg test (9-HPT), neuropsychological scores, and magnetic resonance imaging (MRI) results. Neutralizing antibodies (NAB) were measured. Ten SPMS patients (6 females) with a median EDSS score of 4.5 were enrolled. One patient withdrew because of gastrointestinal complaints, one was withdrawn owing to poor compliance, and 8 patients completed therapy. The only frequent side effect was lymphopenia, reported at least once in all patients. Annual relapse rate was reduced by approximately 50 % in the second year. There was a significant trend for EDSS increase. Total lesion load measured by MRI decreased at 12 and 24 months; only one patient had active lesions. No changes were seen in the 9-HPT. There was a significant improvement in neuropsychological tests after 24 months ( p = 0.045). One patient tested positive for NAB throughout the study, and transient NAB were detected in 4 patients. In conclusion, combination therapy with IFNB-1b and AZA was safe and generally well tolerated in patients with SPMS. Strict clinical and laboratory monitoring is recommended during this combination therapy.
 ...
PMID:Combination therapy with interferon beta-1b and azathioprine in secondary progressive multiple sclerosis. A two-year pilot study. 1219 54

Lymphopenia and increasing viral load in the first 10 days of severe acute respiratory syndrome (SARS) suggested immune evasion by SARS-coronavirus (CoV). In this study, we focused on dendritic cells (DCs) which play important roles in linking the innate and adaptive immunity. SARS-CoV was shown to infect both immature and mature human monocyte-derived DCs by electron microscopy and immunofluorescence. The detection of negative strands of SARS-CoV RNA in DCs suggested viral replication. However, no increase in viral RNA was observed. Using cytopathic assays, no increase in virus titer was detected in infected DCs and cell-culture supernatant, confirming that virus replication was incomplete. No induction of apoptosis or maturation was detected in SARS-CoV-infected DCs. The SARS-CoV-infected DCs showed low expression of antiviral cytokines (interferon alpha [IFN-alpha], IFN-beta, IFN-gamma, and interleukin 12p40 [IL-12p40]), moderate up-regulation of proinflammatory cytokines (tumor necrosis factor alpha [TNF-alpha] and IL-6) but significant up-regulation of inflammatory chemokines (macrophage inflammatory protein 1alpha [MIP-1alpha], regulated on activation normal T cell expressed and secreted [RANTES]), interferon-inducible protein of 10 kDa [IP-10], and monocyte chemoattractant protein 1 [MCP-1]). The lack of antiviral cytokine response against a background of intense chemokine up-regulation could represent a mechanism of immune evasion by SARS-CoV.
 ...
PMID:Chemokine up-regulation in SARS-coronavirus-infected, monocyte-derived human dendritic cells. 1586 Jun 69

Viruses have evolved multiple mechanisms to evade the innate immune response, particularly the actions of interferons (IFNs). We have previously reported that exposure of dendritic cells (DCs) to foot-and-mouth disease virus (FMDV) in vitro yields no infection and induces a strong type I IFN (IFN-alpha and IFN-beta) response, indicating that DCs may play a critical role in the innate response to the virus. In vivo, FMDV induces lymphopenia and reduced T-cell proliferative responses to mitogen, viral effects that may contribute to evasion of early immune responses. In this study we analyzed the in vivo effects of FMDV infection on the IFN-alpha response of two populations of dendritic cells. During the acute phase of infection of swine, production of IFN-alpha from monocyte-derived DCs (MoDCs) and skin-derived DCs (skin DCs) is inhibited. This effect occurs concurrently with rising viral titers in the blood; however, these cells are not productively infected. Interestingly, there are no changes in the capability of these DCs to take up particles and process antigens, indicating that antigen-presenting cell function is normal. These data indicate that inhibition of the IFN-alpha response of dendritic cell populations from blood and skin by FMDV enhances viral pathogenesis in infected animals.
 ...
PMID:Interferon-alpha production by swine dendritic cells is inhibited during acute infection with foot-and-mouth disease virus. 1835 24

Foot-and-mouth disease virus (FMDV) causes an economically devastating disease of cloven-hoofed animals. In this review, we discuss the mechanisms FMDV has evolved to counteract the host innate and adaptive immune responses and the role of viral proteins in this process. The viral leader proteinase, L pro, limits the host innate response by inhibiting the induction of interferon beta (IFN beta) mRNA and blocking host cell translation. A second viral proteinase, 3C pro, may affect host cell transcription because it cleaves histone H3. Viral protein 2B in conjunction with 2C or their precursor 2BC inhibits protein trafficking through the endoplasmic reticulum and Golgi apparatus. A decrease in surface expression of major histocompatibility class I molecules during FMDV infection suggests that 2B, 2C and/or 2BC may be involved in delaying the initiation of the host adaptive immune response and also adversely affect the secretion of induced signaling molecules. FMDV also causes a transient lymphopenia in swine, but the mechanism involved is not understood nor have any viral protein(s) been implicated. Furthermore, the interaction of FMDV with various cells in the immune system including lymphocytes and dendritic cells and the possible role of apoptosis and autophagy in these interactions are discussed.
 ...
PMID:Evading the host immune response: how foot-and-mouth disease virus has become an effective pathogen. 1840 12

We present a 43-year-old woman with relapsing-remitting multiple sclerosis (MS) who developed lupus syndrome after 32 months of IFN-beta-1a therapy. She presented with malaise, myalgia, arthralgia and fever. Laboratory tests showed high erythrocyte sedimentation rate, anaemia and lymphopenia. Antibodies to double stranded DNA (dsDNA) of IgG, IgM and IgA classes were detected on Critidia luciliae. Additionally, high levels of anti-nucleosomal antibodies, low levels of anti-histone and anti-Ro/SSA antibodies were also found. Diagnosis of drug-induced SLE was established. Treatment with IFN-beta was discontinued and oral prednisone was started. Twelve weeks after cessation of IFN-beta therapy, the patient's symptoms completely resolved and autoantibodies disappeared. To the best of our knowledge, this is the first report of a patient with MS in whom treatment with IFN-beta induced lupus syndrome and antibodies to dsDNA and nucleosome.
 ...
PMID:Anti-double stranded DNA and lupus syndrome induced by interferon-beta therapy in a patient with multiple sclerosis. 1907 73

Fingolimod is a derivative of the naturally occurring immunosuppressive substance myriocin, with structural similarity to sphingosine, a ubiquitous sphingolipid. It acts as an immunomodulator interfering with the egress of T and B lymphocytes from secondary lymph organs, which results in lymphopenia. A phase II study in patients with multiple scerosis showed a significant reduction in annual relapse rate and lesions in magnetic resonance imaging with an acceptable rate of side effects. An advantage of fingolimod compared to interferon beta, glatirameracetate and natalizumab is its oral availability. Definitive assessment of the compound has to await the results of trials currently being performed.
 ...
PMID:[Fingolimod - a new immunomodulator]. 1980 64

Alemtuzumab, formally known as Campath-1H, is a humanized monoclonal antibody directed against CD52, a protein on the surface of lymphocytes and monocytes with unknown function. A single dose of alemtuzumab leads to a rapid, profound and prolonged lymphopenia. A Phase II trial has shown that alemtuzumab reduces the risk of relapse and accumulation of disability by over 70% compared with interferon beta in patients with early relapsing-remitting multiple sclerosis (MS). Alemtuzumab has been used in Cambridge as an experimental treatment for MS since 1991. In this review we summarize our experience; describing how this prototypical, "bench-to-bedside" therapy continues to inform basic science, revealing aspects of the pathogenesis of MS and lymphopeniaassociated autoimmunity.
 ...
PMID:Spotlight on alemtuzumab. 1989 40

Foot-and-mouth disease virus (FMDV) causes an acute, highly contagious disease of livestock. Though FMDV is very sensitive to interferon-alpha (IFN-alpha), IFN-beta, and IFN-gamma, the virus has evolved mechanisms to evade such innate responses. For instance, during acute infection, FMDV suppresses IFN-alpha production by skin and myeloid dendritic cells (DCs). We have previously reported that FMDV infection induces a transient lymphopenia and interruption of T-lymphocyte responses to mitogenic stimuli. To further understand the immunopathogenesis of FMD, we have now analyzed the serum IFN-alpha response in relation to lymphopenia, and the number and function of plasmacytoid DCs (pDCs) following infection of pigs with multiple serotypes of FMDV. Serum IFN-alpha peaked 2-3 d post-infection (PI), regardless of FMDV serotype. Lymphopenia coincided with peak viremia and the serum IFN-alpha response. Circulating pDC numbers and in-vitro pDC IFN-alpha secretion transiently declined by 48 h following infection. Infection of lymphocytes or pDCs was never detected regardless of the FMDV serotype inoculated or the age of the animal infected. These data indicate that, like other DC subsets, there is suppression of interferon production by pDCs, which abrogates this important innate response. Rapid induction of serum IFN-alpha, albeit short-lived, may contribute to the rapid resolution of FMDV viremia prior to induction of specific immunity.
 ...
PMID:Loss of plasmacytoid dendritic cell function coincides with lymphopenia and viremia during foot-and-mouth disease virus infection. 2056 98


1 2 Next >>