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Query: UMLS:C0024312 (lymphopenia)
 4,859 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There is both clinical and experimental evidence that cellular and humoral immunity are suppressed in patients with renal insufficiency: observations in organ transplantation and in vitro stimulation of lymphocytes from uraemic patients, investigations of acute and late hypersensitivity reactions, the immune response after active immunization as well as changes of immunoglobulins and lymphatic organs in uraemia are discussed in the paper. The underlying mechanisms are complex and not yet fully understood. Lymphopenia, atrophy of the thymus gland, toxic serum factors, induction of enhancing mechanisms by certain serum fractions and metabolic defects of lymphocytes--all were shown to be involved or at least considered to be. At present, however, it is impossible to define their rank of importance and the exact place they may occupy in the genesis of this type of "natural immunosuppression".
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PMID:[Immune mechanisms in uremia]. 0 May 40

The present study reports of three kinds of experiments of unaffected primary rejection of xenogenous kidney transplanats in the close-related fox-dog species system. The issue is whether there is a relation between the amount of grafted parenchyma and the immune induced potency, that is whether the course of rejection of transplanted single kidneys (group I a) differs from the course after en-bloc transplantation of both kidneys (group I b). In group II alterations of blood chemism and behavior of humoral antibodies are followed in dogs to which a fox kidney was transplanted, while keeping their own functioning kidneys. This experiment is to give information whether the uremic syndrome influences the development of humoral immunity, and what changes of blood chemism may primarily be related to destruction of the graft, under the condition of absent uremia. Untreated graft recipients survived for 5,4 +/- 0,49 days (n = 5) when single kidneys were transplanted (group I a), and 5,2 +/- 0,75 days (n = 5) when both kidneys were grafted en-bloc (group I b). As to the rejecting reactions, both groups are almost equal: the increasing functional failure causes a fast increase of creatinine and urea nitrogen; alkaline phosphatase and LDH show distinct alterations, related to the progress of the graft's destruction. Decrease of albumin level and loss of cholinesterase activity indicate an impaired hepatic function as reaction to uremic intoxication. Gamma-globulins and leucocytes show alterations that can be related to non-specific inflammatory reactions. The immunologically specific initial lymphopenia suggests that after revascularization these cells migrate to the graft, and later react with antigenic structures of vascular endothelium and still later with those of the organ cells. Cytotoxic antibodies appear on the 4th postoperative day in increasing amount. Post mortem histologic examination shows round cell infiltrates in the vastly necrotic renal parenchyma. When the recipient's kidneys are kept in situ and a fox kidney is transplanted (group II) uremia is avoided and the animals survive. During the 30-days period of observation, that is longer than the term of rejection, the titer of cytotoxic antibodies remains stable or tends to increase. LDH and alkaline phosphatase show characteristic changes that are considered sequels from destructed transplantate. The experiments show, aside from certain reservations, that the donor-host combination fox-dog is suitable to serve as preclinic model for human transplantation using xenogenous donors of organs, i. e. anthropoid primates.
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PMID:[The unaffected primary rejection of xenogeneic kidney transplants in the closely related fox-dog species system]. 3 59

To estimate the influence of topical treatment with DMBA and induced tumors on delayed hypersensitivity, the response of spleen lymphocytes to PHA in vitro and macrophage migration inhibition with PHA were studied in DMBA-treated hairless mice. DNA synthesis and blastic transformation of cultured lymphocytes decreased after 6-12 weeks of DMBA application. Lymphocyte response to PHA gradually diminished during the experiment, as compared with control animals. Since the malignant transformation of skin tumors was not observed before 16 weeks of DMBA carcinogenesis, it seems that derangements in cellular immunity preceded the malignant proliferation. The increase in spleen weight and the absence of PHA-induced inhibition of macrophage migration in hairless mice with malignant tumors may also be related to the influence of the tumor itself on the lymphatic system of experimental animals.
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PMID:Immunological phenomena in harmless mice during experimental carcinogenesis induced with long-term topical application of 7, 12-dimethylbenzanthracene (DMBA). 4 67

A 5-year-old girl with a history of recurrent infection and anaemia has no measurable purine nucleoside phosphorylase (N.P.) activity in her red blood-cells. Her serum-immunoglobulin levels are normal, as are her antibody responses to thymus dependent and independent antigens. However, she has severe lymphopenia, pronounced depression of lymphocyte response to mitogenic and allogeneic cell stimuli, and greatly decreased T-cell rosette formation. Her parents are second cousins; their red cells contain less than half the normal level of N.P. activity. They also share an unusual N.P. isozyme pattern indicative of molecular hybridisation between catalytically active and inactive subunits, which strongly supports the assumption that they are heterozygous and their daughter is homozygous for a "silent" allele at the N.P. gene locus. Inherited deficiency of adenosine deaminase, an enzyme catalysing a reaction only one metabolic step away from that of N.P., is known to cause immunodeficiency. It is therefore very likely that this patient's lack of demonstrable N.P. activity is responsible for her syndrome.
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PMID:Nucleoside-phosphorylase deficiency in a child with severely defective T-cell immunity and normal B-cell immunity. 4 76

Peripheral blood T and B lymphocytes were quantitated in 42 patients with untreated Hodgkin's disease and the results compared with the response to phytohemagglutinin (PHA) stimulation and delayed hypersensitivity skin testing. T lymphocytes were identified by an in vitro cytotoxicity assay employing a specific anti-T-cell serum and by spontaneous rosette formation with sheep erythrocytes (E rosettes). The percentage of T cells in the patients was similar to that of normal subjects as judged by the cytotoxicity assay (65 to 90%). In addition, absolute T-lymphocyte counts were normal in 63% of the patients and were generally reduced only in those with lymphopenia. The percentage of T lymphocytes determined by the E-rosette assay was similar to that determined by the cytotoxicity assay in normal controls, but was significantly lower than that determined by the cytotoxicity assay in the patients. Moreover, the decreased response to PHA stimulation in the patients was directly correlated with the decrease in E-rosette formation. These findings suggest that T lymphocytes in the peripheral blood are not generally diminished in untreated Hodgkin's disease. However, a proportion of these cells exhibits altered surface interactions that may account for some aspects of their impaired immunologic function.
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PMID:Quantitation of T and B lymphocytes and cellular immune function in Hodgkin's disease. 5 8

Patients with active systemic lupus erythematosus (SLE) had a decrease in a subpopulation of cells (fraction D) when peripheral blood lymphocytes were separated on a discontinuous Ficoll gradient. Preincubation of SLE cells at 37 degrees C for 30 min led to a marked decrease in this fraction, composed primarily of thymus-derived (T) cells. Supernates of such preincubations were found to cause a reduction in fraction D cells from normal humans. The active factor in the supernate was found to be an IgG antibody. Similarly, serum from patients with active SLE produced a reduction in fraction D cells from normal donors. This activity was also found in the IgG fraction, and could be absorbed with a pure T-cell population. Depletion of macrophages and complement did not reduce the SLE anti-T-cell antibody-mediated loss of cells from fraction D; however, heat-aggregated human gamma globulin led to impairment of the reaction. These findings suggest that antibody-dependent direct lymphocyte-mediated cytotoxicity may play a role in T-cell lymphopenia of SLE. It was further noted that the SLE anti-T-cell antibodies, in contrast to rabbit antihuman thymocyte serum, recognized fraction D cells but not fraction E cells from normals. Since both fractions are largely T cells, it appeared that the SLE serum was directed against cell-membrane antigenic determinants present on fraction D T cells, which were absent or reduced in quantity on fraction E T cells. Thus, evidence was presented indicating the presence of at least two subpopulations of cells in man. This was supported by differential absorption of the anti-T-cell sera with fractions D and E.
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PMID:Fractionation of cells on a discontinuous Ficoll gradient. Study of subpopulations of human T cells using anti-T-cell antibodies from patients with systemic lupus erythematosus. 5 18

For development of an animal model of virus-induced anergy, the effect of canine distemper virus (CDV) upon cell-mediated immunity in dogs was investigated. First, canine cutaneous reactions and in vitro lymphocyte responses to soluble protein antigens were characterized. Dogs immunized with picryl guinea pig albumin and with keyhole limpet hemocyanin (both in complete Freund's adjuvant) responded reproducibly to intracutaneous challenge with these antigens. Reactivity peaked in 20-40 days (maximal induration, 6-50 mm). Lymphocytes from these animals responded in vitro to stimulation with keyhole limpet hemocyanin or purified protein derivative. This stimulation was antigen-specific and was maximal on day 6 of culture. Infection with CDV depressed cutaneous reactivity and lymphocyte response in vitro to antigens and mitogens. This effect was transient in animals previously vaccinated with attenuated CDV; however, gnotobiotic puppies (susceptible to CDV) had prolonged depression of cell-mediated immunity and lymphopenia. Some of these animals developed neurologic symptoms and died. The findings indicate that CDV infection is a potentially useful model for study of virus-induced depression of T (thymus)-cell responses and support the hypothesis that there is more than one mechanism responsible for this phenomenon.
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PMID:A canine distemper model of virus-induced anergy. 5 99

A total of 59 children with chronic otitis media were examined for possible immunological defects by determination of serum gammaglobulin and immunoglobulins IgG, IgA and IgM, and by a tuberculin test, and additionally by noting any lymphopenia. Some divergence from normal values was found in 38 patients (64%). 14 children (24%) showed pathologically low immunoglobulin levels and 7 (12%) even a subtotal absence of one of the immunoglobulin fractions. 8 of the cases (14%) also showed a reduction of gammaglobulin level. In 20 children (34%), the level of one or more of the three major Ig classes was elevated. All except one became clinically normal within a few years, showing normal gamma or immunoglobulin levels when tested. The tuberculin test was positive in all patients. The length and course of the disease in these cases was similar to that in patients with normal test values. Gammaglobulin therapy did not have any beneficail effect. Consequently, it is concluded that although humoral immunological defects may be one aetiological factor, they do not play any major role in the course of chronic otitis media in children.
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PMID:Immunological defects in children with chronic otitis media. 6 88

In studies of the mouse thymus, lymphocyte mitoses are seen to be most frequent in the thymus cortex. There is evidence from thymic grafts that a hypothetical factor, thymopoietin, may stimulate mitosis of thymic lymphocytes. It is a factor which is postulated to act in conjunction with the PAS-positive mesenchymal reticular cells and epithelial reticular cells of the cortex. The thymus medulla is necessary for the integrity of thymic grafts, and may also elaborate a secretion for maintaining the cellular functions of the gland. Thymectomy has been used as a gauge for judging normal thymic function and results, in the mouse, in lymphopenia, degeneration of spleen and lymph nodes, delayed rejection of skin allografts, reduced ability of spleen cells to mount the graft versus host reaction, and reduced primary immune response to certain antigens. Correction of these deficiencies offers a means of evaluating various thymic extracts and grafts. Lymphocytosis-stimulating hormone (LSH) is known to maintain the peripheral lymphoid organs and cause lymphocytosis in the thymectomized animal. Diffusion chamber studies of thymic grafts also show restored lymphoid tissue by a cell-free factor (CIF). These two factors may be the same and probably represent the basis of the highly purified lymphocyte-stimulating proteins, LSHr and LSHh, which restore the L/P ratio in thymectomized animals and may stimulate lymphopoiesis in spleen and lymph nodes. LSHr, unlike LSHh, increases the total lymphocyte count. LSHr has been found to increase the humoral antibody response in neonatal mice both by the PFC technique and by direct hemolysis of sheep erythrocytes. Homeostatic thymic hormone (HTH) is a thymic extract of small molecular weight and contains nucleic acid. In the thymectomized guinea pig it has been found to maintain normal levels of lymphocytes in the blood, spleen and lymph nodes, to restore antibody titers to typhoid H antigen and to restore the toxic allergic reaction. Thymic humoral factor (THF) is of smaller molecular weight (less than 1,000) and probably is not a protein. It also enhances lymphoid proliferation in neonatally thymectomized mice. There is evidence that THF participates in humoral antibody formation because it stimulates PFC formation from neonatally thymectomized mice after inoculation with sheep erythrocytes. Its effects on cell-mediated immunity are seen from findings that injection of THF restores the ability of thymectomized mice to reject skin allografts. THF enables spleen cells from thymectomized or neonatal animals to mount the graft versus host reaction, and causes maturation of bone marrow cells and spleen or lymph node cells so that they can participate in the graft versus host reaction. It has been reported to stimulate lymphocytes to kill isogeneic tumor cells in vitro. Thymosin is protein extracted from the thymus. It has been found to alleviate leukopenia slightly and provide some improvement in lymphoid histology in thymectomized mice...
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PMID:Some endocrine aspects of the thymus gland. 6 31

In spite of the increasing use of single and multiple pharmacologic intravenous pulses of MPS for immunosuppression in various diseases, their immunosuppressive effects have not been documented. We treated two groups of six patients with classic RA unresponsive to conventional therapy with either one or three daily 1 gm intravenous doses of MPS and measured the immune response and clinical activity over 16 weeks. Lymphocytopenia with selective T lymphocyte suppression was noted 2 hr following each infusion, which was maximal at 6 hr with complete recovery 24 hr after each dose beyond which no lymphocytopenia or T lymphocyte depletion was seen. Preservation of skin test positivity to recall antigens such as PPD and histoplasmin, rise in antibody titers to the secondary antigens tetanus and typhoid, and primary antibody response to KLH were found in both groups after treatment. Serum gamma globulin concentrations were unchanged. Five of six patients receiving 3 doses and three of six receiving 1 dose had satisfactory improvement in clinical parameters, with maximal benefit seen within the first 4 days. Six patients still felt better at 4 weeks, and one patient in each group entered a clinical remission greater than 16 weeks. We conclude that higher and repeated doses of MPS caused neither greater lymphocytopenia nor more prolonged suppression of recirculating lymphocytes than the conventional oral doses. The clinical benefits stem from reduction of inflammation, and it is doubtful that pulse therapy by itself induced significant generalized immunosuppression.
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PMID:Effect of corticosteroids on the human immune response: comparison of one and three daily 1 gm intravenous pulses of methylprednisolone. 7 67


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