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)

We describe the phenotypic characteristics of animals in the fifth backcross-intercross generation of a breeding program in which the RT1 u haplotype and the phenotypic trait responsible for the T-lymphopenia of BB rats have been transferred to the ACI background. In this generation of animals, 24% were lymphopenic with decreased numbers of PBL expressing CD5, TCR alpha, and RT6. The PBL of the lymphopenic animals had a decreased mitogenic response to ConA. All of the nonlymphopenic animals were homozygous for RT6.2. Phenotypic analysis of intestinal IEL revealed that this was also the case for the lymphopenic animals. Moreover, IEL of the lymphopenic animals exhibited a pattern of staining (increased numbers of TCR alpha beta+CD4+CD8+ and decreased numbers of TCR alpha beta+CD4-CD8+) similar to that of BB DP animals. The ACI.1U(BB)-lymphopenic animals, although having two of the genetic traits associated with the expression of spontaneous diabetes mellitus, uniformly fail to develop diabetes. Breeding studies in which these animals were crossed with BB and hBB rats suggest that other genes are necessary for development of overt diabetes.
 ...
PMID:Polygenic nature of spontaneous diabetes in the rat. Permissive MHC haplotype and presence of the lymphopenic trait of the BB rat are not sufficient to produce susceptibility. 144 3

Evidence of an acquired T cell-specific deficiency distinct from acquired immunodeficiency syndrome (AIDS) in a 63-yr-old Japanese female is provided. Recently, this patients suffered from primary invasive pulmonary aspergillosis. Skin tests to purified protein derivative of tuberculin (PPD) and Aspergillus antigens were negative. Upon admission to our hospital, her lymphocytes were exclusively unresponsive to T cell mitogens (concanavalin A, phytohemagglutinin, and OKT 3). The level of cells defined by monoclonal antibodies (CD1, CD2, CD3, CD4, WT31, and CD5) was less than 3%. In contrast, no decrease in the number of red blood cells, platelets, neutrophils or B cells was apparent. Five years ago, the patient had a normal white blood cell and lymphocyte count. However, over the following 4 yr, she developed lymphopenia. With medication, her pulmonary disease recovered, while lymphopenia still continued. The levels of immunoglobulins, complements and enzyme activities (adenosine deaminase and purine nucleoside phosphorylase) were normal. Moreover, several tests for HIV (ELISA and Western bolt) were negative suggesting that the T cell-specific deficiency was not a congenital immunodeficiency or AIDS but rather a new type of acquired immunodeficiency.
 ...
PMID:Acquired T cell specific deficiency other than acquired immunodeficiency syndrome (AIDS). 156 29

As part of a study of the therapeutic potential of anti-T cell monoclonal antibodies, we studied the biologic effects of 8BE6, a mouse anti-guinea pig (GP) pan-T cell monoclonal antibody, on blood and tissue T cells and on the prototypic T cell-mediated reactions, classic delayed hypersensitivity (DH) and cutaneous basophil hypersensitivity (CBH). 8BE6 reacts to a 68,000 m.w. protein probably homologous with human CD5 (T1) and murine Lyt-1. A single dose of 1.8 to 3.4 mg 8BE6 caused lymphopenia and greater than 90% depletion of 8BE6+ peripheral T cells 1 to 72 hr later, and a significant but lesser decrease of lymphocytes reacting with another pan-T cell monoclonal antibody (p less than 0.02 at 24 hr). Free serum 8BE6 was detected for up to 48 hr after administration. Immunoperoxidase stains of tissue revealed that lymphocytes in lymph nodes and spleen were coated with mouse immunoglobulin 1 hr after antibody treatment and displayed in situ capping. Subsequently, there was a loss of T cells in all tissues (spleen, lymph node, liver, and kidney) except the thymus, with normal 8BE6 antigen staining returning by 72 hr. Areas of induration of DH reactions to PPD were reduced in 8BE6-treated GP, compared with pretreatment reactions in the same GP or in control-treated GP (p less than 0.001 for both). The numbers of infiltrating T cells and fibronectin-receptor-positive macrophages were also reduced. In contrast, 8BE6 had no effect on CBH reactions, as judged by erythema and basophil counts in 1-micron sections, although fewer T cells were found in reaction sites. There were no differences in IgM, fibronectin, or Ia staining between 8BE6-treated GP and controls. In vivo administration of a single dose of anti-T cell monoclonal antibody results in a transient, highly specific depletion of T cell populations in peripheral blood and tissues except the thymus. This treatment inhibits DH but not CBH reactions by systemic and local depletion of T cells.
 ...
PMID:Anti-T cell monoclonal antibodies in vivo. I. Inhibition of delayed hypersensitivity but not cutaneous basophil hypersensitivity reactions. 349 71

B cell dysregulation is a hallmark of human immunodeficiency virus infection. Since B lymphocytes comprise two distinct subpopulations, CD5+ and CD5- cells, we addressed their individual phenotypic and functional behavior. Seropositive patients with both limited and advanced disease progression had an increased percentage of peripheral blood CD5+ B cells, compared to seronegative controls (20.1 +/- 2.1 and 22.7 +/- 5.7, respectively, vs 17.0 +/- 3.4 in controls); however, due to the lymphopenia and reduced number of circulating B cells in infected individuals, the absolute number of CD19+CD5+ lymphocytes was actually reduced. Although HIV-specific antibodies were synthesized spontaneously in vitro only by CD5- B cells, a 10-fold lower degree of spontaneous, non-HIV-specific activation was also displayed by unstimulated CD5+ B cells. These findings indicate that B cell dysregulation during HIV infection involves both the CD5- and the CD5+ B cell compartments; moreover, in view of the putative role of CD5+ B cells in autoimmune phenomena and IL-10 production, these data reinforce the possibility that B cell dysfunction might be causally involved in AIDS pathogenesis.
 ...
PMID:B cell activation and human immunodeficiency virus infection. V. Phenotypic and functional alterations in CD5+ and CD5- B cell subsets. 750 25

The developmental biology of sheep ileal and jejunal Peyer's patches (PP) was investigated using corticosteroids to deplete immature B lymphocytes. During a 7-day treatment with dexamethasone, ileal PP follicular (iPf)B-cell proliferation was arrested and most iPfB-cells died. This resulted in follicular involution with the survival of mesenchymal cells. No iPfB-cell proliferation was detected in follicular remnants for 4 weeks postdexamethasone treatment, and during a subsequent 3-month period, there was limited iPfB-cell proliferation that resulted in a partial regeneration of follicles. Ileal PP involution was also associated with a severe B lymphopenia that persisted for over 14 weeks and was characterized by the survival of primarily isotype-switched and CD5+ sIgM+ B-cells in blood. In contrast, the size of jejunal PP follicles was reduced following dexamethasone treatment, but intrafollicular B-cell proliferation was not arrested. Furthermore, within 4 weeks, the jejunal PP follicles had recovered in size and cellularity and there was no disruption in IgA plasma-cell production. Thus, dexamethasone selectively depleted iPfB-cells and revealed that the ileal and jejunal PPs contain functionally distinct B-cell populations. The partial regeneration of the iPfB-cell population indicated that either an intrafollicular, corticosteroid-resistant B-stem cell existed or that ileal PP follicles can be repopulated by circulating B-cells. Finally, the association between ileal PP involution and the absence of circulating, CD5- B-cells confirmed that this lymphoid tissue provides an essential environment for conventional sIgM+ B-cell development.
 ...
PMID:Two distinct pathways of B-cell development in Peyer's patches. 892 62

In this study, the effects of induced whole body hyperthermia (WBH; 42.3 degrees C for 90 min) on peripheral blood mononuclear cell (PBMC) phenotype distribution, in vitro blastogenic responsiveness and selected parameters of hemostasis were determined in dogs. Hyperthermia was induced by heating venous blood during extracorporeal circulation (EC); induction of WBH by peritoneal lavage (PL) and perfusion without heating (i.e. euthermic EC and euthermic PL) were used as controls. Whole body hyperthermia was associated with lymphopenia and thrombocytopenia that persisted throughout the eight-day post-treatment observation interval. The lymphopenia was selective in that CD5-positive T lymphocytes were more sensitive than were sIg-positive B cells and, within the T-cell compartment, suppressor (CD8-positive) cells were more sensitive to hyperthermic stress than helper (CD4 positive) lymphocytes. Lymphopenia was also observed in EC and PL euthermic controls, although that lymphopenia was transient and nonselective. Persistent suppression of T-cell phytomitogen-induced blastogenesis was induced by WBH in contrast to transient suppression in euthermic controls. For all treatment groups, lymphopenia and suppressed blastogenesis were correlated to elevated plasma cortisol levels. Induction of WBH by EC resulted in coagulopathy characterized by thrombocytopenia, increased plasma fibrin degradation products, prolonged clotting times, and evidence of spontaneous bleeding. These hemostatic alterations were correlated temporally to increased serum levels of liver enzymes. However, there was no evidence of hepatic injury when WBH was induced by PL, where transient thrombocytopenia was the only significant hemostatic alteration. These results indicate that 42.3 degrees C whole body hyperthermia can be well-tolerated and, although associated with suppression of general indexes of immunocompetence, is not associated with opportunistic infections.
 ...
PMID:Whole body hyperthermia: effects upon canine immune and hemostatic functions. 1050 4

Activation of immunoregulatory T lymphocyte subsets has been observed in dengue viral infection, being more evident in dengue hemorrhagic fever (DHF) than in classical dengue fever (DF). There are, however, as yet no well-defined host markers to determine which patients with dengue viral infection will develop severe complications during the acute febrile stage of the disease. A study was performed to compare the cellular immune status in DHF, DF and non-dengue viral infections (NDF) in order to determine the value of these parameters in distinguishing DHF from classic DF and other viral infections during the acute febrile stage of the disease. This study involved 109 febrile patients admitted because of suspected DHF. Fifty patients were serologically confirmed cases of dengue infection, of which 25 had grade 1 or 2 DHF. There was a reduction in total T (CD3), CD4 and CD8 cells in DHF and demonstrated that a low level of CD3, CD4, CD8 and CD5 cells discriminated DHF from DF patients during the febrile stage of the illness. In contrast, B (CD19) cells and natural killer (NK) cells did not appear to be discriminatory in this study. Receiver operating characteristic (ROC) curve analysis showed that a combination of CD3 cell of < or = 45% and CD5 cell of < or = 55% was the best marker to identify DHF patients (sensitivity = 84% and specificity = 52% for CD3 cell of < or = 45%; sensitivity = 92% and specificity = 71% for CD5 cell of < or = 55%). CD4 cell of < or = 25% and CD8 cell < or = 30% were equally good in discriminating DHF from DF patients. On the other hand, the ROC curves indicated no clear difference between the immunoregulatory cell counts in DF from NDF Lymphopenia, atypical lymphocytosis and thrombocytopenia were significantly more evident in dengue compared to non-dengue infection but did not appear to be discriminatory among DHF and DF patients. The reduction in CD3, CD4, CD8, CD5 cells correlated with the degree of thrombocytopenia in DHF (p < 0.05) which suggests that these cells probably participate in a common pathogenetic mechanism.
 ...
PMID:Quantitation of T lymphocyte subsets helps to distinguish dengue hemorrhagic fever from classic dengue fever during the acute febrile stage. 1092 65

The objective of this study was to contribute to a better characterization of the immunological profile of idiopathic myelofibrosis (IM) at presentation by analysing the blood lymphocyte subsets and their possible correlations with other disease features. Absolute blood lymphocytes and lymphocyte subsets were assessed in 31 IM patients, compared with those from 34 healthy individuals, and correlated with the patients' main clinical, hematological and bone marrow histologic features. The mean lymphocyte count of the IM patients was 1.1 (SD 0.6) x 10(9)/L, versus 1.6 (SD 0.49) x 10(9)/L in controls (p = 0.0006), with 24 of the 31 patients (77.4%) showing lymphocytopenia (< 1.5 x 10(9)/L). IM patients had significantly lower counts of CD3, CD4, CD8, and CD3 -/ CD56+ cells, and significantly higher CD3 +/CD56 + lymphocyte counts. Although no significant differences were found between patients and controls with regard to CD19+/CD5+ cell counts, increased CD5 + B-cell lymphocytes were observed in three IM patients. In one of the latter patients, Ig gene rearrangement analysis of the heavy chain gene demonstrated such a subpopulation to be clonal, but the patient did not develop features of chronic lymphoid leukemia during a 5-yr follow-up. No correlation was found between the patients' blood lymphocyte counts and other disease features. We conclude that most IM patients have absolute lymphopenia, decreased T cells and increased cytotoxic T cells at diagnosis, and 10% of them show an increased CD5 + B-cell subpopulation.
 ...
PMID:Assessment of peripheral blood lymphocyte subsets in idiopathic myelofibrosis. 1096 69

We previously demonstrated that the rat thymus undergoes a progressive remodelling long before the appearance of typical signs of involution [Quaglino, D., Capri, M., Bergamini, G., Euclidi, E., Zecca, L., Franceschi, C., Pasquali Ronchetti, I., 1998. Age-dependent remodelling of rat thymus. Morphological and cytofluorimetric analysis from birth up to one year of age. Eur. J. Cell. Biol. 76, 156-166]. To focus better on the complex remodelling that occurs in the rat immune system during the first year of life, we analysed the phenotype profile of thymocytes, and T lymphocytes from mesenteric lymph nodes and peripheral blood of the same animals by flow cytometry. Two experimental sets were performed simultaneously using the same animal strain, but starting and ending the study at different ages (15 days up to 300 days in the first experimental set, and 90 days up to 360 days of life in the second). In the rat these ages appear to be crucial not only for developmental, maturative and early involutional processes of the thymus, but also of the entire immune system. The main findings were the following: (1) in the thymus, CD8(-)CD4(-) cells increased, CD5(+)alphabeta TCR(-) and CD8(+)CD4(+) thymocytes decreased, while the most mature cell subset appeared well preserved with ageing; (2) in the lymph nodes, T helper and T cytotoxic lymphocytes decreased in the most aged animals. Memory/activated CD4(+)CD45RC(-) T cells decreased, while naive/resting CD4(+)CD45RC(+) cells increased in the youngest animals and decreased in the oldest. CD8(+)CD45RC(-) and CD8(+)CD45RC(+) lymphocytes showed a complex age-dependent trend, and (3) in peripheral blood, minor modifications were evident, such as an age-dependent increase in the alphabeta TCR(+)CD25(+) cell subset. Some of these changes were related to the developmental process, while others could likely be interpreted as early signs of immunosenescence. The role of these modifications in immune system is discussed within the framework of the remodelling hypothesis of immunosenescence. The age-dependent changes in these three lymphoid compartments, however, appear to be different and only partially overlapping, thus suggesting that the maturational, developmental and ageing processes have distinct characteristics in the central and peripheral lymphoid organs.
 ...
PMID:A cytofluorimetric study of T lymphocyte subsets in rat lymphoid tissues (thymus, lymph nodes) and peripheral blood: a continuous remodelling during the first year of life. 1097 83

We investigated the distribution of B and T cells in the peripheral blood of haematologically inconspicuous (non-persistent lymphocytotic, PL-) cattle infected with the bovine leukaemia virus (BLV). Flow cytometric data were obtained from six PL- cattle and compared with six age-matched animals with persistent lymphocytosis (PL+) and five non-infected healthy controls (BLV-). In the PL- group, the percentage and number of surface immunoglobulin-positive (sIg+) B cells were significantly reduced. Whereas in BLV-cattle, about 40% of the peripheral blood lymphocytes (PBL) were sIg + and 24% were sIgM + B cells. In the PL- group, less than 20% of the PBL were sIg+ and sIgM+ B cells. Only 5% of the PBL co-expressed sIgM+ and CD5+ versus 16% in BLV-. This decrease was persistent over 3 years and predominantly affected: (i) B cells that did not express sIgM; (ii) sIgM + B cells co-expressing CD5 and CD11b; and (iii) equally both lambda- and K-type light chain B-cell subpopulations. In contrast, the number of all circulating lymphocytes, CD5- and CD11b- sIgM+ B cells and CD2+ T cells did not differ. In PL+ animals, about 75% of the PBL were sIgM+ CD5+ B cells. These cells were of polyclonal origin, as light chains of the lambda- and K-type were expressed in a ratio of 4:1 (57.7% of PBL lambda+, 14% kappa+) as in BLV- animals (33.6% of PBL lambda+, 8.7% kappa+). In PL+ cattle the absolute number of B-cells and, therefore, their relative percentage is significantly increased. For this reason, even in case of absolutely increased T-cell numbers, the relative percentage of T-cells could be lower than in normal controls. The cause for the observed B cell decrease in PL- cattle is unknown, but it can be assumed that cytotoxic T cells are involved in this B-cell lymphopenia.
 ...
PMID:Cattle infected with bovine leukaemia virus may not only develop persistent B-cell lymphocytosis but also persistent B-cell lymphopenia. 1224 Oct 26


1 2 Next >>