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1.
Curr Oncol ; 27(2): e123-e145, 2020 04.
Article in English | MEDLINE | ID: mdl-32489262

ABSTRACT

Background: In Ontario, there is no clearly defined standard of care for staging for distant metastasis in women with newly diagnosed and biopsy-confirmed breast cancer whose clinical presentation is suggestive of early-stage disease. This guideline addresses baseline imaging investigations for women with newly diagnosed primary breast cancer who are otherwise asymptomatic for distant metastasis. Methods: The medline and embase databases were systematically searched for evidence from January 2000 to April 2019, and the best available evidence was used to draft recommendations relevant to the use of baseline imaging investigation in women with newly diagnosed primary breast cancer who are otherwise asymptomatic. Final approval of this practice guideline was obtained from both the Staging in Early Stage Breast Cancer Advisory Committee and the Report Approval Panel of the Program in Evidence-Based Care. Recommendations: These recommendations apply to all women with newly diagnosed primary breast cancer (originating in the breast) who have no symptoms of distant metastasis Staging tests using conventional anatomic imaging [chest radiography, liver ultrasonography, chest-abdomen-pelvis computed tomography (ct)] or metabolic imaging modalities [integrated positron-emission tomography (pet)/ct, integrated pet/magnetic resonance imaging (mri), bone scintigraphy] should not be routinely ordered for women newly diagnosed with clinical stage i or stage ii breast cancer who have no symptoms of distant metastasis, regardless of biomarker status. In women newly diagnosed with stage iii breast cancer, baseline staging tests using either anatomic imaging (chest radiography, liver ultrasonography, chest-abdomen-pelvis ct) or metabolic imaging modalities (pet/ct, pet/mri, bone scintigraphy) should be considered regardless of whether the patient is symptomatic for distant metastasis and regardless of biomarker profile.


Subject(s)
Breast Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Neoplasm Metastasis , Neoplasm Staging
2.
Curr Oncol ; 24(3): e185-e190, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28680285

ABSTRACT

PURPOSE: A large body of evidence clearly shows that cancer patients experience significant health benefits with smoking cessation. Cancer Care Ontario, the provincial agency responsible for the quality of cancer services in Ontario, has undertaken a province-wide smoking cessation initiative. The strategies used, the results achieved, and the lessons learned are the subject of the present article. METHODS: Evidence related to the health benefits of smoking cessation in cancer patients was reviewed. A steering committee developed a vision statement for the initiative, created a framework for implementation, and made recommendations for the key elements of the initiative and for smoking cessation best practices. RESULTS: New ambulatory cancer patients are being screened for their smoking status in each of Ontario's 14 regional cancer centres. Current or recent smokers are advised of the benefits of cessation and are directed to smoking cessation resources as appropriate. Performance metrics are captured and used to drive improvement through quarterly performance reviews and provincial rankings of the regional cancer centres. CONCLUSIONS: Regional smoking cessation champions, commitment from Cancer Care Ontario senior leadership, a provincial secretariat, and guidance from smoking cessation experts have been important enablers of early success. Data capture has been difficult because of the variety of information systems in use and non-standardized administrative and clinical processes. Numerous challenges remain, including increasing physician engagement; obtaining funding for key program elements, including in-house resources to support smoking cessation; and overcoming financial barriers to access nicotine replacement therapy. Future efforts will focus on standardizing processes to the extent possible, while tailoring the approaches to the populations served and the resources available within the individual regional cancer programs.

3.
Eye (Lond) ; 28(3): 318-26, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24384961

ABSTRACT

PURPOSE: To evaluate the morphological and functional changes following intravitreal Ozurdex (dexamethasone implant) injections in patients with macular oedema (MO) secondary to retinal vascular diseases. DESIGN: This is a single centre, exploratory phase III, prospective, open-label clinical study. METHODS: Thirty patients with MO secondary to retinal vascular disorders underwent assessments for best corrected visual acuity, contrast sensitivity, microperimetry, chromatic sensitivity, macular thickness, and morphology using spectral domain optical coherence tomography (SD-OCT) and fluorescein angiography at baseline. They were treated with intravitreal Ozurdex at baseline and monitored monthly with visual acuity and SD-OCT assessments up to 36 weeks. Re-treatment was permitted from 16 to 24 weeks according to pre-defined criteria. All visual function tests were repeated at 24 weeks. RESULTS: The mean change in central sub-field thickness (CST) from baseline was significant at all visits up to 32 weeks. The lowest mean CST was recorded at 8 weeks and the highest mean ETDRS score was achieved at 12 weeks. All visual functions except contrast sensitivity improved significantly by 24 weeks. The study showed that the ideal re-treatment time point based on functional and structural outcomes and known side-effects of Ozurdex treatment is at 20 weeks. CONCLUSION: Ozurdex therapy has a rapid and dramatic effect on the macula for about 8 weeks followed by a sustained modest effect up to week 32. The optimal re-treatment time point is at 20 weeks.


Subject(s)
Dexamethasone/administration & dosage , Diabetic Retinopathy/complications , Glucocorticoids/administration & dosage , Macular Edema/drug therapy , Retinal Vein Occlusion/complications , Tomography, Optical Coherence , Vitreous Body/drug effects , Adult , Aged , Aged, 80 and over , Contrast Sensitivity/physiology , Dexamethasone/adverse effects , Diabetic Retinopathy/physiopathology , Drug Implants , Drug Monitoring , Female , Fluorescein Angiography , Glucocorticoids/adverse effects , Humans , Macular Edema/etiology , Macular Edema/physiopathology , Male , Middle Aged , Prospective Studies , Retinal Vein Occlusion/physiopathology , Retreatment , Time Factors , Visual Acuity/physiology
4.
BMJ ; 320(7234): 577-8; author reply 579, 2000 Feb 26.
Article in English | MEDLINE | ID: mdl-10744401
5.
J Virol ; 72(7): 6233-6, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9621096

ABSTRACT

Primate polyomavirus genomes all contain an open reading frame at the 5' end of the late coding region called the agnogene. A simian virus 40 agnoprotein with unknown functions has previously been demonstrated. We now show that a BK virus agnoprotein appears in the perinuclear area and cytoplasm late in the infectious cycle. It is phosphorylated in vivo and coimmunoprecipitates with a subset of host cell proteins.


Subject(s)
BK Virus/chemistry , Viral Proteins/analysis , BK Virus/genetics , Humans , Phosphorylation , Precipitin Tests , Viral Proteins/genetics , Viral Proteins/metabolism , Viral Regulatory and Accessory Proteins
6.
Br Dent J ; 182(11): 424-9, 1997 Jun 14.
Article in English | MEDLINE | ID: mdl-9217339

ABSTRACT

OBJECTIVE: To investigate the use of an oral pathology service by general dental practitioners over a 20-year period. DESIGN: Retrospective analysis of the number of cases received for histological examination in 1975, 1984 and 1994. SETTING: Birmingham Dental Hospital. SUBJECTS AND METHODS: 1101, 2395 and 3366 specimens were accessed respectively for the three years studied. Number and proportion of specimens received, number and proportion that were hard or soft tissue specimens and the information on the request form were recorded. A comparison was made between the provisional clinical and histological diagnoses. RESULTS: Although the number of specimens accessed increased approximately 3-fold, the number of specimens accessed from general dental practitioners increased 5-fold. The variety of histological categories increased by over 50%, most being soft tissue specimens. The number of correct provisional diagnoses increased steadily but the percentage with inappropriate provisional diagnoses remained the same. Information on request forms steadily improved. CONCLUSIONS: The increased number of specimens received from general dental practitioners over the 20-year period reflects an increased demand for an oral pathology diagnostic service. The referral pattern most likely indicates an increased awareness by general dental practitioners of the need to biopsy lesions arising within the oral cavity.


Subject(s)
Diagnostic Services/statistics & numerical data , Pathology Department, Hospital/statistics & numerical data , Pathology, Oral/statistics & numerical data , Practice Patterns, Dentists'/statistics & numerical data , Biopsy/statistics & numerical data , Dental Service, Hospital/statistics & numerical data , Diagnostic Errors/statistics & numerical data , England , General Practice, Dental/statistics & numerical data , Humans , Mouth Diseases/diagnosis , Mouth Neoplasms/diagnosis , Pathology, Oral/methods , Pathology, Oral/organization & administration , Referral and Consultation/statistics & numerical data , Retrospective Studies
7.
Am J Trop Med Hyg ; 56(5): 576-9, 1997 May.
Article in English | MEDLINE | ID: mdl-9180611

ABSTRACT

To assess the effect of the Expanded Program on Immunization (EPI) in rural Africa, blood samples were collected in two Kenyan sublocations. Serum antibodies against tetanus toxoid were measured in 155 individuals 1-70 years of age. Titers greater than the protective level of 0.01 IU/ml were found in 47% of the population. Protection was significantly higher in children born after the launching of the EPI (68%) and in women who had been at childbearing age since then (69%). Significantly lower protection was demonstrated in other age and sex-groups. The level of protection in children was equal in the two populations, whereas protection in fertile women was significantly lower in the population living a long distance from a health center. Diphtheria anti-toxin was measured in the samples from one sublocation, and 70 of 84 individuals (83%) had antibody levels greater than the protective level. No age or sex difference could be found, and there was no correlation between response levels to diphtheria and tetanus. This implicates natural infections as an important source of diphtheria antibodies. Our findings demonstrate a need for better coverage of the adult population against tetanus. Furthermore, diphtheria transmission still appears to take place, underscoring the importance of diphtheria vaccination of travelers to rural Africa.


Subject(s)
Diphtheria/immunology , Tetanus/immunology , Adolescent , Adult , Aged , Antibodies, Bacterial/blood , Child , Female , Humans , Immunization , Male , Middle Aged
8.
Proc Natl Acad Sci U S A ; 92(26): 12393-7, 1995 Dec 19.
Article in English | MEDLINE | ID: mdl-8618908

ABSTRACT

Although the origin of autoimmune antibodies to double-stranded DNA is not known, the variable-region structures of such antibodies indicate that they are produced in response to antigen-selective stimulation. In accordance with this, results from experiments using artificial complexes of DNA and DNA-binding polypeptides for immunizations have indicated that DNA may induce these antibodies. Hence, the immunogenicity of DNA in vivo may depend upon other structures or processes that may render DNA immunogenic. We report that in vivo expression of a single DNA-binding protein, the polyoma virus T antigen, is sufficient to initiate production of anti-double-stranded DNA and anti-histone antibodies but not a panel of other autoantigens. Expression of a mutant, non-DNA-binding T antigen did result in strong production of antibodies to the T antigen, but only borderline levels of antibodies to DNA and no detectable antibodies to histones. Nonexpressing plasmid DNA containing the complete cDNA sequence for T antigen did not evoke such immune responses, indicating that DNA by itself is not immunogenic in vivo. The results represent a conceptual advance in understanding a potential molecular basis for initiation of autoimmunity in systemic lupus erythematosus.


Subject(s)
Antigens, Polyomavirus Transforming/biosynthesis , Autoantibodies/biosynthesis , DNA-Binding Proteins/biosynthesis , DNA/immunology , Histones/immunology , Lupus Erythematosus, Systemic/immunology , 3T3 Cells , Animals , Antigens, Polyomavirus Transforming/immunology , Autoantigens/immunology , Autoimmunity , Base Sequence , DNA Primers , DNA, Complementary , DNA-Binding Proteins/immunology , Enzyme-Linked Immunosorbent Assay , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Plasmids , Polymerase Chain Reaction/methods , Promoter Regions, Genetic
9.
Chirurg ; 66(7): 735-8, 1995 Jul.
Article in German | MEDLINE | ID: mdl-7671763

ABSTRACT

Among the different pathologic structures of the presacrococcygeal space retrorectal cystic hamartomas are uncommon lesions. These cysts are most likely derived from remnants of the embryonic tailgut although an association to teratomas may exist. We describe the clinicopathologic features of a retrorectal cystic hematoma with malignant transformation in a 60 year old female patient. The literature is reviewed and etiology, diagnosis and operative management are discussed.


Subject(s)
Adenocarcinoma, Mucinous/pathology , Cell Transformation, Neoplastic/pathology , Hamartoma/pathology , Rectal Neoplasms/pathology , Sacrum/pathology , Spinal Neoplasms/pathology , Adenocarcinoma, Mucinous/surgery , Female , Hamartoma/surgery , Humans , Middle Aged , Rectal Neoplasms/surgery , Rectum/pathology , Sacrum/surgery , Spinal Neoplasms/surgery
10.
Clin Exp Immunol ; 100(2): 239-45, 1995 May.
Article in English | MEDLINE | ID: mdl-7743662

ABSTRACT

The T cell response was studied in 25 patients suffering from cutaneous leishmaniasis caused by Leishmania major with severe (n = 10) and mild (n = 15) disease manifestations. Peripheral blood mononuclear cells (PBMC) from the patients were activated by sonicates of Leishmania promastigotes (LMP) and amastigotes (LDA), and the surface protease gp63. The proliferative responses to Leishmania antigens were lower in patients with severe disease than in patients with mild disease (P = 0.01-0.05), and such a difference was not observed in the response to purified protein derivative of tuberculin (PPD) or tetanus toxoid (TT). LMP-induced interferon-gamma (IFN-gamma) production was lower in patients with severe than in patients with mild disease (P < 0.05). When the IL-4 and IFN-gamma responses of each patient were considered, two response patterns were observed in the cultures activated by the Leishmania sonicates. One response pattern was characterized by high production of IFN-gamma without production of IL-4 (a Th1-like pattern), the other was characterized by low IFN-gamma levels which in most cases were associated with IL-4 production (not a Th1-like pattern). These patterns could not be distinguished when the cells from the same donors were stimulated by TT and PPD. The percentages of patients with a Th1-like response pattern after stimulation by LMP in patients with severe and mild disease manifestations were 30% and 80%, respectively. This difference was statistically significant (P = 0.034).


Subject(s)
Antigens, Protozoan/immunology , Interferon-gamma/metabolism , Interleukin-4/metabolism , Leishmaniasis, Cutaneous/immunology , T-Lymphocytes/immunology , Animals , Leishmania major , Leishmaniasis, Cutaneous/diagnosis , Lymphocyte Activation , Th1 Cells/immunology , Th2 Cells/immunology
11.
Exp Clin Endocrinol Diabetes ; 103(6): 391-7, 1995.
Article in English | MEDLINE | ID: mdl-8788313

ABSTRACT

Somatostatin (SRIF) is effective in the nonoperative management of a variety endocrine tumors. A potential role of SRIF for treatment of patients with primary hyperparathyroidism (pHPT) has been suggested. In a controlled, prospective, triple-blinded, randomized clinical trial, the somatostatin analogue octreotide (SMS 201-995, Sandostatin) was evaluated in 40 patients with well documented pHPT. Amongst other biochemical parameters, serum calcium and-phosphate and levels of parathyroid hormone, calcitonin, and osteocalcin as well as octreotide were assessed before and for 4 hours after a single iv. application of 200 micrograms ocreotide or placebo. SRIF-receptor autoradiography was performed in parathyroid tissue samples. Baseline values revealed a constellation of biochemical parameters typically found in pHPT. Following 200 micrograms octreotide, no significant changes in any of the biochemical parameters investigated for were observed. Multivariate analysis was performed to identify patient subpopulations in which any given combination of laboratory parameters changed in response to either drug or placebo. However, no 'responders' to octreotide were identified. 45% of patients receiving octreotide, reported side effects. Parathyroid tissue samples were negative for SRIF-receptor expression. It is concluded that a single dose iv. application of octreotide does not result in appreciable changes of biochemical parameters relevant in pHPT and carries a high rate of side effects. Furthermore, absence of SRIF-receptors in parathyroid tissue from patients with pHPT, together with lack of octreotide effects, suggests that somatostatin-analogues may not be effective in the non-operative therapy of pHPT.


Subject(s)
Hormones/therapeutic use , Hyperparathyroidism/drug therapy , Octreotide/therapeutic use , Adolescent , Adult , Aged , Autoradiography , Calcitonin/blood , Calcium/blood , Female , Humans , Hyperparathyroidism/metabolism , Hyperparathyroidism/pathology , Male , Middle Aged , Multivariate Analysis , Octreotide/blood , Osteocalcin/blood , Parathyroid Glands/chemistry , Parathyroid Glands/pathology , Parathyroid Hormone/blood , Phosphates/blood , Prospective Studies , Receptors, Somatostatin/analysis
12.
Scand J Immunol ; 40(6): 629-35, 1994 Dec.
Article in English | MEDLINE | ID: mdl-7997852

ABSTRACT

The major surface protease of Leishmania major, gp63, has been suggested as a vaccine candidate for cutaneous leishmaniasis. In this study gp63 was purified from L. major promastigotes. A panel of human T-cell clones recognizing this protein were generated from individuals who had previously had self-healing cutaneous leishmaniasis. The T-cell clones expressed CD4, and the alpha chain of the T-cell antigen receptor. GP63 reactive T-cell clones activated by antigen or by immobilized anti-CD3 antibody released relative large amounts of interferon-gamma and no or little interleukin-4, thereby resembling Th1 cells. Autologous mononuclear cells and Epstein-Barr virus-transformed B cell lines were equally efficient in presenting the antigen to the T cells. The gp63 reactive T cells induced resistance to infection in cultured human macrophages by L. major. The data confirm that human CD4+ T cells recognizing gp63 can take part in the host defence against L. major infections.


Subject(s)
Antigens, Protozoan/immunology , Leishmania major/immunology , Macrophages/immunology , Macrophages/parasitology , Metalloendopeptidases/immunology , Th1 Cells/immunology , Adult , Animals , Clone Cells , Flow Cytometry , Humans , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis
13.
J Immunol Methods ; 173(2): 149-56, 1994 Aug 01.
Article in English | MEDLINE | ID: mdl-8046249

ABSTRACT

Production of antisera against proteins that are not amenable to easy purification is most efficiently achieved by expressing the protein as a fusion product in bacteria. However, smaller polypeptides may present difficulties, since the majority of the antibodies may be directed against the fusion partner if the whole fusion protein is used as immunogen, while the target peptide alone may be a poor immunogen due to its small size. We have circumvented this problem through the use of two different fusion partners. The first fusion protein is used for priming the immune response and the first boost, while another fusion partner is substituted for the second boost. Five different polypeptides derived from the human polyomavirus BK, ranging in molecular weight from 4400 (39 amino acid residues) to 11,500 (96 amino acid residues), were used to test this approach. The results obtained indicate that this procedure may be very useful in raising antibodies against small antigens.


Subject(s)
Antibodies, Viral/biosynthesis , Antigens, Viral/immunology , BK Virus/immunology , Glutathione Transferase/immunology , Recombinant Fusion Proteins/immunology , beta-Galactosidase/immunology , Animals , Antibodies, Viral/blood , Antigens, Viral/genetics , BK Virus/genetics , Base Sequence , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression Regulation, Bacterial , Glutathione Transferase/genetics , Immune Sera/immunology , Immunization , Immunization, Secondary , Molecular Sequence Data , Rabbits , Recombinant Fusion Proteins/genetics , beta-Galactosidase/genetics
14.
Clin Exp Immunol ; 96(3): 410-5, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8004809

ABSTRACT

The T cell response to antigens from Leishmania major promastigotes was investigated in peripheral blood mononuclear cells from Sudanese individuals with a history of cutaneous leishmaniasis (CL), Sudanese individuals with positive DTH reaction in the leishmanin skin test but with no history of skin lesions, and in Danes without known exposure to Leishmania parasites. Proliferation and production of interferon-gamma (IFN-gamma) and IL-4 in antigen-stimulated cultures was measured. Lymphocytes from individuals with a history of CL proliferated vigorously and produced IFN-gamma after stimulation with either a crude preparation of L. major antigens or the major surface protease gp63. These cultures produced no or only little IL-4. Also cells from leishmanin skin test-positive donors with no history of CL produced IFN-gamma and no IL-4 in response to L. major antigens. Cells from the unexposed Danes were not activated by gp63. The cells from Danish donors produced either IFN-gamma or IL-4, but not both cytokines after incubation with the crude preparation of L. major antigens. The data show that the T cell response to Leishmania antigens in humans who have had uncomplicated CL or subclinical L. major infection is an IFN-gamma-producing Th1-like response.


Subject(s)
Antigens, Protozoan , Leishmania major/immunology , Leishmaniasis, Cutaneous/immunology , T-Lymphocytes/immunology , Animals , Humans , Hypersensitivity, Delayed , In Vitro Techniques , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis , Lymphocyte Activation , Metalloendopeptidases/immunology , Protozoan Proteins/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Helper-Inducer/immunology , Tetanus Toxoid/immunology , Tuberculin/immunology
15.
Clin Exp Immunol ; 96(3): 416-21, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8004810

ABSTRACT

The T cell response to different Leishmania donovani antigens was investigated using peripheral blood mononuclear cells (PBMC) from Kenyans cured of visceral leishmaniasis and non-exposed Danes. Crude promastigote and amastigote antigens both induced proliferation and interferon-gamma (IFN-gamma) production in PBMC from cured patients, while cells from non-exposed donors gave weak responses. A similar pattern was induced by lipophosphoglycan-associated protein (LPGAP). By contrast, the major surface protease of Leishmania, gp63, induced only a weak proliferative response without IFN-gamma production in five of 17 samples from cured patients. Four of the five responding cultures produced IL-4, i.e. the response to this antigen was of the Th2 type. Furthermore, sera from acutely ill visceral leishmaniasis patients contained high levels of IgG antibodies to gp63. The Th2-like response to gp63 in patients cured of visceral leishmaniasis differs from the Th1-like response to the same antigen observed in patients cured of cutaneous leishmaniasis.


Subject(s)
Leishmania donovani/immunology , Leishmaniasis, Visceral/immunology , Protozoan Proteins/immunology , T-Lymphocytes/immunology , Animals , Antibodies, Protozoan/blood , Antigens, Protozoan , Glycosphingolipids/immunology , Humans , In Vitro Techniques , Interferon-gamma/biosynthesis , Interleukin-4/biosynthesis , Lymphocyte Activation , Metalloendopeptidases/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Helper-Inducer/immunology
16.
J Immunol ; 152(9): 4542-8, 1994 May 01.
Article in English | MEDLINE | ID: mdl-7908919

ABSTRACT

The effect of Leishmania major and L. donovani surface protease gp63 on surface markers on human T cells was studied using fluorescence-activated flow cytometry. Purified gp63 (63,000 m.w. glycoprotein) at concentrations above 10 micrograms/ml completely inhibited binding of six different anti-CD4 Abs to human T cells, whereas the binding of one Ab, OKT4, was not inhibited. Heat inactivation of the protease before the incubation with cells abolished the effect on binding of anti-CD4 Abs. Cells incubated for 2 h with the protease and subsequently washed free of the protease showed a gradual re-expression of CD4, reaching 50% of the initial level after 72 h of incubation in medium. Preincubation of cells with live promastigotes showed an inhibitory effect on CD4 comparable to that seen with purified gp63. The binding of Abs directed against other surface markers present on human T-cells--CD2, CD3, CD5, CD8, CD11A, CD25, CD45RO, CD45RA, CD58, TCR-alpha, TCR-gamma, and HLA DQ--was not inhibited by gp63. These data suggest that gp63, both in its purified form and in the form anchored to the parasite membrane, cleaves CD4 on human T cells. The cleavage of CD4 by the protease might play a role in interfering with the induction of the immune response and thus disease progression in Leishmania infections.


Subject(s)
CD4 Antigens/metabolism , Metalloendopeptidases/immunology , Protozoan Proteins/immunology , Animals , Antibodies, Monoclonal/metabolism , Binding, Competitive , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/parasitology , Humans , In Vitro Techniques , Leishmania donovani/immunology , Leishmania major/immunology , Metalloendopeptidases/metabolism , Protozoan Proteins/metabolism
17.
APMIS ; 102(4): 265-71, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8011303

ABSTRACT

In the present study the effect of Leishmania major surface protease Gp63 on the chemotaxis and oxidative burst response of human peripheral blood monocytes and neutrophils was investigated. It was shown that prior incubation of cells with Gp63 inhibited chemotaxis of neutrophils but not monocytes towards the chemotactic peptide f-met-leu-phe. On the other hand, chemotaxis of both neutrophils and monocytes towards zymosan-activated serum containing C5a was inhibited by Gp63. Monocyte and neutrophil chemiluminescence response to opsonized zymosan was reduced by preincubation of the cells with Gp63 in a concentration-dependent manner. Notably, monocytes were inhibited to a much greater degree than neutrophils by a given concentration of Gp63, and they were also inhibited at much lower concentrations of the protease. The inhibitory effect of Gp63 on chemotaxis and chemiluminescence was completely abolished by heat inactivation of the protease at 70 degrees C for 15 min. Neither neutrophil nor monocyte chemiluminescence was inhibited by Gp63 when cells were stimulated with PMA. Our data suggest that the major surface protease Gp63 might play an important role in the initial stages of Leishmania/macrophage interactions and the intracellular survival of the parasite.


Subject(s)
Leishmania major/immunology , Metalloendopeptidases/immunology , Monocytes/immunology , Neutrophils/immunology , Animals , Chemotaxis, Leukocyte , Humans , In Vitro Techniques , Luminescent Measurements , Membrane Glycoproteins/immunology , Protozoan Proteins/immunology , Respiratory Burst
18.
APMIS ; 101(8): 642-6, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8105816

ABSTRACT

An enzyme-linked immunosorbent assay (ELISA) using native gp63 for detection of serum antibodies to Leishmania was evaluated. The test identified antibodies in sera from 16 of 16 visceral leishmaniasis (VL) patients and 9 of 12 sera from patients with Trypanosoma brucei infection. In comparison, sera from 80 Danish controls and 40 control donors from a malaria endemic area of Ghana without known exposure to Leishmania were negative, as were sera from 12 Kenyan malaria patients and 9 schistosomiasis patients. After cure of VL, sera rapidly became negative. Only 1 of 7, 1 of 21, and 1 of 27 sera from cured VL patients 6-12 months, 1-2 years and > 2 years after cure were positive. Thus, in contrast to other serological tests for VL, the gp63 ELISA seems to distinguish an ongoing from a past infection. This might prove useful both for diagnostic and epidemiological purposes.


Subject(s)
Antibodies, Protozoan/analysis , Leishmania donovani/immunology , Leishmaniasis, Visceral/diagnosis , Metalloendopeptidases/immunology , Protozoan Proteins/immunology , Animals , Antibodies, Helminth/analysis , Enzyme-Linked Immunosorbent Assay , Humans , Kenya/epidemiology , Leishmania donovani/metabolism , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/immunology , Metalloendopeptidases/metabolism , Protozoan Proteins/metabolism , Schistosoma mansoni/immunology , Trypanosoma brucei brucei/immunology , Trypanosomiasis, African/diagnosis , Trypanosomiasis, African/immunology
19.
Trans R Soc Trop Med Hyg ; 87(4): 423-4, 1993.
Article in English | MEDLINE | ID: mdl-8249071

ABSTRACT

Two soluble antigens from Leishmania donovani of 116 kDa and 70 kDa molecular mass, and a soluble mixture of crude antigens, were used in an enzyme-linked immunosorbent assay (ELISA) for the detection of visceral leishmaniasis (VL) in the field, and compared with the direct agglutination test (DAT). The tests were carried out on 8 VL patients, 34 normal individuals from an area endemic for the disease, and 68 former visceral leishmaniasis patients 1-5 years after treatment. The 70 kDa ELISA and the DAT had a sensitivity and specificity of 100% (95% confidence interval 63-100%), while the 116 kDa ELISA and the soluble crude antigen ELISA were 37.5% (9-76%) and 50% (16-84%) sensitive, respectively. When using ELISA (116 kDa or 70 kDa), 68-69% of sera tested 1-2 years, and 92-94% of sera tested 5 years, after treatment were negative. In contrast, when DAT or ELISA with crude antigen were used, the negativity rate was 31% 1-2 years, and 53% 5 years, after treatment. DAT was therefore not an accurate test for diagnosis in the field. The use of the 70 kDa antigen in ELISA was an accurate alternative to DAT in the detection of VL.


Subject(s)
Antigens, Protozoan/immunology , Leishmania donovani/immunology , Leishmaniasis, Visceral/diagnosis , Agglutination Tests , Animals , Enzyme-Linked Immunosorbent Assay/methods , False Positive Reactions , Humans , Leishmaniasis, Visceral/drug therapy , Leishmaniasis, Visceral/immunology , Sensitivity and Specificity , Time Factors
20.
Eur J Immunogenet ; 19(6): 403-12, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1477092

ABSTRACT

Mannan-binding protein (MBP) is a lectin which, upon binding to certain carbohydrates, activates the classical pathway of complement without the involvement of antibody or C1q. Deficiency of the MBP is associated with an opsonic defect and recurrent infections during early life. An amino acid substitution in the exon 1 at codon 54 in the MBP gene (GGC [glycine] to GAC [aspartic acid]) has been shown to be closely associated with low MBP concentration in Caucasoids. The gene frequency of the mutant allele in this population has been estimated at 0.13. In the study described here, we investigated the association between the mutant allele and MBP protein concentration in Eskimos from East-Greenland and black Africans from the Baringo District in Kenya. The frequency of the GAC allele was identical in Eskimos and Caucasoids (0.13). No overlap with regard to MBP concentration between the genotypes was found in the Eskimos. In contrast, the Africans revealed a low frequency of the GAC allele (0.009). However, the median MBP protein concentration was approximately 5 times lower among the Africans than the Eskimos. In 12.6% of the Africans and in 2.5% of the Eskimos, MBP was undetectable. Thus, MBP deficiency is the most frequent immunodeficiency so far described. The high prevalence of MBP deficiency among healthy individuals indicates that MBP deficiency also confers some selective advantages. We advance the hypothesis that MBP deficiency is maintained in populations because MBP deficiency decreases the infectivity of some intracellular micro-organisms which are dependent on opsonization.


Subject(s)
Carrier Proteins/blood , Carrier Proteins/genetics , Mannans/metabolism , Polymorphism, Genetic , Adolescent , Adult , Alleles , Asian People , Base Sequence , Black People , Collectins , DNA/genetics , Female , Gene Frequency , Genetic Variation , Greenland , Humans , Immunologic Deficiency Syndromes/blood , Immunologic Deficiency Syndromes/genetics , Inuit , Kenya , Male , Middle Aged , Molecular Sequence Data
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