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

The antiviral nucleoside analogue 2',3'-dideoxycytidine (ddC) is a DNA chain terminator and/or inhibitor of human immunodeficiency virus (HIV) reverse transcriptase. We evaluated the effects of ddC in 36 New Zealand white rabbits. Three/sex were assigned to a control group and 5 treatment groups (10-250 mg/kg/day) for 13 or 18 weeks. Blood samples were taken 1 week prior to treatment and weekly thereafter to termination with the exception of the 2 highest dose groups, where blood sample collection was terminated at week 13. Selected hematological analytes were measured weekly with the exception of prothrombin time (PT) and activated partial thromboplastin time (APTT). PT and APTT and selected biochemical analytes were measured prior to treatment, at 7 weeks, and after 13 weeks of treatment. All rabbits were necropsied. Giemsa and hematoxylin and eosin sections were prepared from methacrylate-embedded marrow. Hematological effects included decreases in red blood cell count, hemoglobin, hematocrit, and white blood cell count and increases in mean corpuscular volume and red cell distribution width. Platelets, platelet volume, PT, APTT, and mean corpuscular hemoglobin concentration values were variable or unchanged. Effects were dose-related, most were seen at 1 week, and they persisted to term. Bone marrow histopathologic changes included megalocytosis, erythroid hypoplasia, bizarre erythroid nuclear morphology, nuclear-cytoplasmic asynchrony, and increased mitotic figures. Lymphopenia caused by ddC plateaued at 2 weeks and persisted until termination. Heteropenia (neutropenia) was sporadic. Biochemical values for serum analytes were unchanged by treatment. The principal hematological effect of ddC upon the erythron was characterized as a nonregenerative macrocytic anemia with erythroid hypoplasia and megaloblastic erythropoiesis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hematological effects of 2',3'-dideoxycytidine in rabbits. 133 36

With the advent of standard flow cytometric methods using two-colour fluorescence on samples of whole blood, it is possible to establish the ranges of CD3, CD4 and CD8 T lymphocyte subsets in the routine laboratory, and also to assist the definition of HIV-1-related deviations from these normal values. In 676 HIV-1-seronegative individuals the lymphocyte subset percentages and absolute counts were determined. The samples taken mostly in the morning. The groups included heterosexual controls, people with various clotting disorders but without lymphocyte abnormalities as well as seronegative homosexual men as the appropriate controls for the HIV-1-infected groups. The stability of CD4% and CD8% values was demonstrated throughout life, and in children CD4 values less than 25% could be regarded as abnormal. The absolute counts of all T cell subsets decreased from birth until the age of 10 years. In adolescents and adults the absolute numbers (mean +/- s.d.) of lymphocytes, CD3, CD4 and CD8 cells were 1.90 +/- 0.55, 1.45 +/- 0.46, 0.83 +/- 0.29 and 0.56 +/- 0.23 x 10(9)/l, respectively. In patients with haemophilia A and B the mean values did not differ significantly. In homosexual men higher CD8 levels were seen compared with heterosexual men and 27% had an inverted CD4/CD8 ratio but mostly without CD4 lymphopenia (CD4 less than 0.4 x 10(9)/l). However, some healthy uninfected people were 'physiologically' lymphopenic without having inverted CD4/CD8 ratios. When the variations 'within persons' were studied longitudinally over a 5-year period, the absolute CD4 counts tended to be fixed at different levels. As a marked contrast, over 60% of asymptomatic HIV-1+ patients exhibited low CD4 counts less than 0.4 x 10(9)/l together with inverted CD4/CD8 ratios. Such combined changes among the heterosexual and HIV-1-seronegative homosexual groups were as rare as 1.4% and 3%, respectively. For this reason, when the lymphocyte tests show less than 0.4 x 10(9)/l CD4 count and a CD4/CD8 ratio of less than unity, the individuals need to be investigated further for chronicity of this disorder, the signs of viral infections such as HIV-1 and other causes of immunodeficiency.
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PMID:Laboratory control values for CD4 and CD8 T lymphocytes. Implications for HIV-1 diagnosis. 134 72

Cats with or without chronic feline immunodeficiency virus (FIV) infection were exposed to feline herpesvirus, type 1 (FHV-1). FIV infected cats became sicker than non-FIV infected cats and required more supportive treatment. However, there were no differences in the length of their illness or in the levels and duration of FHV-1 shedding. FHV-1 infection caused a transient neutrophilia at Day 7 with a rapid return to preinfection levels. The neutrophilia coincided with a transient lymphopenia that was accompanied by a decline in both CD4+ and CD8+ T-lymphocytes. A brief decrease in the CD4+/CD8+ T-lymphocyte ratio occurred at Day 14 in both FIV infected and non-infected cats. This decrease was mainly the result of an absolute and transient increase in CD8+ T-lymphocytes. CD4+ and CD8+ T-lymphocyte numbers and CD4+/CD8+ T-lymphocyte ratios returned to baseline within 4-8 weeks in both FIV infected and non-infected cats. FIV infected cats produced less FHV-1 neutralizing antibodies during the first 3 weeks of infection than non-FIV infected animals. The IgM FHV-1 antibody response was depressed in FIV infected cats whereas the IgG antibody response was unaffected. FHV-1 infection evoked a comparable transient loss of lymphocyte blastogenic responses to concanavalin A and pokeweed mitogen in both FIV infected and non-infected cats. However, response to pokeweed mitogen took longer to return to normal in FIV infected animals. Lymphocytes from FIV infected cats had a greater and more sustained proliferative response to FHV-1 antigen than non-FIV infected cats. The ongoing IgG antibody response to FIV was not affected by FHV-1 infection.
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PMID:Interaction of acute feline herpesvirus-1 and chronic feline immunodeficiency virus infections in experimentally infected specific pathogen free cats. 136 11

Three strains of virus isolated from peripheral blood mononuclear cells (PBMC) of sick cats were identified as feline immunodeficiency virus (FIV) on the basis of in vitro cytopathic effect, T-lymphotropism, ultrastructural morphology and magnesium-dependent reverse-transcriptase activity. The pathogenic properties of two isolates were studied in 13 experimentally infected cats. The primary phase of infection was characterised by a range of haematological (neutropenia, lymphopenia, presence of atypical lymphocytes) and clinical alterations (fever, various signs lasting several weeks, generalised lymphadenopathy persisting for several months) and specific seroconversion. A correlation between the inoculated dose of virus and the intensity and duration of clinical signs was observed. The primary phase was followed in the 10 surviving cats by a stage of asymptomatic seropositivity of undetermined duration but which has persisted for over 35 months for the earliest infections. Viruses reisolated several weeks or months after experimental infection retained the same in vitro properties as the initial isolates.
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PMID:In vitro properties and experimental pathogenic effect of three strains of feline immunodeficiency viruses (FIV) isolated from cats with terminal disease. 137 38

We describe an unusual example of cellular immunodeficiency associated with interleukin-2 deficiency in an otherwise healthy 15-year-old boy who had isolated cryptococcal osteomyelitis of the scapula at 10 years of age. His previous medical history was remarkable only for prolonged, severe varicella infection at 6 years of age. He had persistent moderate lymphopenia, anergy, and absent lymphocyte blastogenic responses to mitogens, antigens, or monoclonal T cell antibodies. Subnormal blastogenic responses were seen after exposure to high concentrations of phorbol esters. Immunoglobulin levels and specific antibodies were normal. The patient has been in good health since treatment of his osteomyelitis. However, his lymphocyte blastogenic responses to mitogens have remained absent during 4 years of observation; investigation of the cause revealed a specific interleukin-2 deficiency resulting from defective generation of interleukin-2 messenger ribonucleic acid. Secretion of interleukin-1 by monocytes was normal, suggesting that the abnormal blastogenic response and interleukin-2 production were due to a problem intrinsic to T lymphocytes. The generation of messenger ribonucleic acid for interleukin-4 was not affected. Interferon-gamma was produced at subnormal levels. The addition of recombinant interleukin-2 restored lymphocyte blastogenic responses and increased the expression of interleukin-2 receptors. The clinical findings and immunologic abnormalities present in this patient differ from other primary and secondary immunodeficiencies associated with interleukin-2 deficiency. Thus our observations in this patient extend the spectrum of immunodeficiencies associated with abnormalities in the production of this important cytokine.
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PMID:Cryptococcal osteomyelitis and cellular immunodeficiency associated with interleukin-2 deficiency. 144 48

A retrospective study was done to determine the prevalence of anti-HTLV-I antibodies in patients with pulmonary cryptococcosis. None of the 19 patients with pulmonary cryptococcosis had underlying immunodeficiency. Anti-HTLV-I antibody was present in 6 (32%) of 19 patients with pulmonary cryptococcosis, a significantly higher prevalence than found in patients with bronchial asthma (4 (7%) of 58) (p less than 0.01, chi-square test). No statistical difference was noted when anti-HTLV-I antibody seropositivity was compared to that of patients with pulmonary tuberculosis (16% (17/105)), lung cancer (17% (22/129)) and pneumonia (9% (6/64)). A reduced cellular immunity as shown by lymphopenia, the CD4/CD8 ratio, and purified protein derivative skin test was found in only 1 (5%) of 19, 2 (12%) of 17, and 6 (33%) of 18 patients, respectively. These results do not explain the susceptibility to pulmonary cryptococcosis in HTLV-I carriers. This is the first report of high prevalence of pulmonary cryptococcosis in HTLV-I carriers and it raises the question whether HTLV-I carriers are more susceptible to opportunistic infections and other malignancies probably due to subtle immunological abnormalities.
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PMID:Prevalence of HTLV-I antibody in pulmonary cryptococcosis. 145 16

The present article describes the clinical and pathological findings in 5 human immunodeficiency virus (HIV)-infected patients with muscle toxoplasmosis. The patients had marked lymphopenia (5/5), with less than five CD4+ cells/mm3 (3/3), when they developed fever (5/5), and multiorgan failure (5/5), including diffuse encephalitis, pneumonia, pancytopenia, and myopathy. Muscle involvement included weakness and wasting (4/5), myalgias (3/5), and high serum creatine kinase levels (3/3). Serology for toxoplasmosis showed high IgG titers in 3 patients (3/4). Anti-Toxoplasma therapy resulted in complete recovery in 2 patients. Muscle toxoplasmosis was detected by biopsy (3/5) or postmortem evaluation (2/5), and was identified using immunocytochemistry and electron microscopy. Toxoplasma cysts were detected in 0.5 to 4% of muscle fibers close to or remote from necrotic fibers and inflammatory infiltrates. Muscle fibers strongly expressed the major histocompatibility complex class I antigen (2/2) as in polymyositis. We suggest that Toxoplasma gondii should be sought by muscle biopsy in patients who have acquired immunodeficiency syndrome with fever, encephalitis, multiorgan dysfunction, and elevated serum creatine kinase levels of obscure origin.
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PMID:Skeletal muscle toxoplasmosis in patients with acquired immunodeficiency syndrome: a clinical and pathological study. 145 37

A variant of simian immunodeficiency virus (SIVSMM/PBj), isolated from a chronically infected pig-tailed macaque has been shown in previous studies to produce acutely fatal disease uniformly in pig-tailed macaques and in some rhesus macaques. The present study extends investigation of SIVSMM/PBj pathogenesis in rhesus and cynomolgus monkeys. Cynomolgus and rhesus macaques were found to be uniformly susceptible to infection, but as previously reported, the rhesus were found to not be uniform in their response during the acute disease. Homogenized tissues from a rhesus that died acutely from SIVSMM/PBj were passaged to 6 rhesus monkeys in an attempt to increase lethality. Five of 6 rhesus monkeys receiving intravenous inoculation of either spleen (10(3) TCID50) or lymph node (10(5) TCID50) homogenate developed acute disease; 4 died (days 8-10), 1 recovered, and one rhesus remained asymptomatic. Three of 3 cynomolgus macaques and 4 of 4 pig-tailed macaques receiving the same inoculum died acutely within 9 days. Clinical disease in macaques that died was characterized by diffuse lymphadenopathy within 5 days of inoculation and severe diarrhea beginning 1 to 3 days before death. Anorexia, lymphopenia (< 1000 cells/mm3), and mild hypoalbuminemia preceded onset of diarrhea by 24 h. Viral p27 was detected in circulation by day 6 postinfection, with all animals dying acutely having detectable serum p27 and no detectable humoral response. Acute lethality was attributed to severe metabolic acidosis (pH < 7.20) which was observed 24-48 h prior to death in the pig-tailed and cynomolgus macaques. Immunohistochemistry revealed numerous SIV antigen-positive lymphocytes and macrophages in the lymph nodes, spleen, gut-associated lymphoid tissues and gastrointestinal lamina propria. Histopathologic lesions included marked to severe hyperplasia of the T-cell-dependent areas in lymphoid tissues and diffuse nonulcerative lymphohistiocytic gastroenteritis. Surviving rhesus developed strong humoral immune responses to the major SIV proteins.
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PMID:Infection of rhesus and cynomolgus macaques with a rapidly fatal SIV (SIVSMM/PBj) isolate from sooty mangabeys. 145 9

A family including three children with DiGeorge syndrome is described. One child died in the neonatal period from cardiac anomalies accompanying complete DiGeorge syndrome. The two surviving siblings shared a common set of pharyngeal pouch anomalies and immunodeficiency consistent with partial DiGeorge syndrome, and other morphologic anomalies characteristic of the velocardiofacial syndrome with which familial DiGeorge syndrome is associated (reviewed in reference 1). Both had normal karyotypes. Both presented with recurrent otitis media and sinopulmonary infections, CD4+ T cell lymphopenia, and defective DCH skin test responses to recall T cell antigens. Both had low serum IgM levels and IgG4 levels at the lower limits of normal. Immunization with bacterial polysaccharides resulted in impaired IgG antibody responses to the same set of antigens (H. influenzae polyribophosphate and S. pneumoniae capsular serotypes 9N and 14), while responses to protein antigens were intact. Both siblings were treated successfully with intravenous gamma globulin. The pattern of selective antibody deficiency in these patients with familial DiGeorge syndrome suggests a heritable lesion in certain regulatory antipolysaccharide CD4+ T cell subpopulations.
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PMID:Selective polysaccharide antibody deficiency in familial DiGeorge syndrome. 152 80

The Wiskott-Aldrich syndrome (WAS) is an inherited disease involving defects of platelets (small size, severe thrombocytopenia due to accelerated destruction) and T lymphocytes (progressive immunodeficiency, lymphopenia). The best-characterized molecular defect is the deficiency and, in some cases, abnormal forms of the T-lymphocyte surface mucin molecule CD43; deficiency of the platelet surface mucin GPIb was observed previously in two of four patients. Neither of these defects is primary, since CD43 and GPIb are encoded by autosomal genes and the disease is X-linked. This study uses cellular biological approaches to explore the possibility that destruction of structurally defective WAS platelets, mimicked experimentally by sonication of normal platelets, plays a role by releasing protease and generating other cellular defects. We show that a protease of normal platelets, identified as Ca(2+)-dependent neutral protease (calpain), which is known to cleave platelet GPIb, also specifically cleaves CD43 on the surface of neighboring desialylated T lymphocytes. The identification of the CD43 cleaving protease was based on its requirement for Ca2+ and inhibition by leupeptin, but not by diisopropylfluorophosphate (DFP). The approximate site of CD43 cleavage was identified by the use of a rabbit antibody. Sensitivity of GPIb to calpain is shown to be sialylation-independent and that of CD43 to be sialylation-dependent, and these findings are explained in terms of molecular structures. These and previous findings are incorporated into a putative mechanism, which explains most of the defects in the WAS. The mechanism suggests that the primary defective molecule in the WAS is unlikely to be a surface glycoprotein, but rather a cytoplasmic molecule with a function in cytoskeletal interactions and/or calcium ion regulation and calpain activation.
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PMID:Effect of platelet calpain on normal T-lymphocyte CD43: hypothesis of events in the Wiskott-Aldrich syndrome. 155 70


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