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J van Lunzen

Publications and source records attributed to J van Lunzen.

16 recordsLinked to original sources
PubMed1996

Coinfection of individual leukocytes with human cytomegalovirus and human immunodeficiency virus is a rare event in vivo.

Infection with the human cytomegalovirus (HCMV) accelerates disease progression in human immunodeficiency virus 1 (HIV-1)-infected individuals. This has been attributed to the transaction of HIV-1 gene expression by HCMV gene products. For transactivation to be effective in vivo both viruses must be present in the same cell. We therefore examined blood samples from 13 HIV-1-infected patients with HCMV viremia for coinfection of individual leukocytes. In four of the patients lymph nodes were also examined. Multiple samples contained defined numbers (between 10 and 1000) of CD4+ lymphocytes or CD14+ monocytes were sorted by a FACS-based automated cell deposition unit. Samples were then analysed by a multiplex nested polymerase chain reaction, which can detect simultaneously HCMV and HIV DNA. The percentage of infected cells was calculated for each virus using the Poisson distribution. Between 0.43% and 6.2% of the CD4+ lymphocytes were infected with HIV and less than 0.15% with HCMV. The level of infection in CD14+ monocytes was always < or = 0.11% for HIV and ranged between < 0.05% and 0.58% for HCMV. Only seven of 1030 sorted samples from blood were positive for both viruses. In lymphnodes, none of the 144 samples tested were double-positive. This clearly shows that coinfection of individual human leukocytes with HIV and HCMV is a very rare event in vivo. Therefore, direct transactivation of HIV by HCMV in coinfected cells obtained from blood and lymphnodes may not explain the effect of HCMV on the prognosis of HIV-infected individuals.

AIDS-Related Opportunistic Infections↗
PubMed1996

Loss of antibody reactivity directed against the V3 domain of certain human immunodeficiency virus type 1 variants during disease progression.

We have previously shown that in AIDS patients a predominant species of infectious virus can be found which is not neutralized by homologous serum. The presence of the infectious virus was associated with the lack of type-specific antibody directed against the V3 domains of these virions. In contrast to this lack of V3-specific antibody, the other V3 domains of non-infectious virions were well recognized by antibody. To determine whether the lack of a V3-specific antibody response is due to a progressive loss of antibody during human immunodeficiency virus type 1 (HIV-1) infection, we monitored the anti-V3 antibody response in 90 patients over time. Anti-V3 antibodies were monitored by a V3-specific ELISA using 21 different V3 domains as a fusion with glutathione S-transferase (GST-V3) based upon sequences from 11 HIV-1 patient isolates and 10 sequences from an HIV-1 B subtype consensus-like GST-V3 expression library. This strictly heterologous screening showed a loss of V3-specific antibodies in 20 out of the 90 patients tested. To study the in vivo relevance of these findings we analysed V3 antibody loss in two patients. This strictly autologous antibody screening was performed based upon V3 sequences of the patients' cell-free virions. In both patients the loss of a V3-specific antibody could be detected in parallel to a decline of CD4+ T cells. Moreover, the escape of a distinct V3 variant was shown to correlate closely with the loss of the V3-specific antibody.

Amino Acid Sequence↗
PubMed1996

Visceral leishmaniasis emerging as an important opportunistic infection in HIV-infected persons living in areas nonendemic for Leishmania donovani.

BACKGROUND: Visceral leishmaniasis is an important infection in patients infected with human immunodeficiency virus and living in areas endemic for Leishmania sp. Leishmaniasis, however, is rarely suspected in patients residing in nonendemic countries. METHODS: Retrospective case analysis of 15 patients with human immunodeficiency virus infection and leishmaniasis treated at seven German clinics. The clinicopathological features and the diagnostic role of biopsy and/or cytology as compared to serology were evaluated. RESULTS: All patients were severely immunocompromised. One patient was first diagnosed at autopsy. One patient with mucocutaneous disease was diagnosed by nasal biopsy. All others had amastigotes detected in bone marrow (13/13), liver (3/3), and gastrointestinal mucosa (4/4). Serology was positive in only 6 or 13. CONCLUSION: Visceral leishmaniasis is an important opportunistic infection in patients with acquired immunodeficiency syndrome and it must be ruled out in every patient with fever and/or pancytopenia and an appropriate travel history. Because serological diagnosis is often insufficient, pathologists must be aware of the association between human immunodeficiency virus infection and leishmaniasis. Diagnosis depends on detection of the parasite in submitted specimens.

AIDS-Related Opportunistic Infections↗
PubMed1996

Rapid plasma virus and CD4+ T-cell turnover in HIV-1 infection: evidence for an only transient interruption by treatment.

OBJECTIVES: To analyse the short-term kinetics of viral plasma RNA and CD4+ T cells numbers in patients with different initial CD4+ T-cell counts treated with different antiretroviral regimens. METHODS: In 10 HIV-1 positive patients, in vivo kinetics of plasma HIV RNA and CD4+ T cells were studied during antiretroviral treatment. Lymphocyte subpopulation analysis, quantitative polymerase chain reaction (PCR), p24 antigen enzyme immunoassay (EIA) and beta 2-microglobulin EIA were performed at days 0, 3, 7, 10, 14, 21 and 28 of treatment. One additional patient served as a control. The resulting curves were fitted. Half-lives were calculated using the time constant T of decrease or increase [T1/2 = In(2) x T]. Calculations of virus and CD4+ T-cell turnover were multiplied by the total blood volume. RESULTS: Viral plasma RNA half-life ranged from 1.1 to 5.1 days, independent of prior or actual treatment and initial CD4+ T-cell count. The calculated peripheral blood viral plasma RNA turnover varied between 0.02 and 55.8 x 10(8) copies/ml/day and showed some negative correlation with initial CD4+ T-cell counts. CD4+ T-cell turnover estimates ranged from 0.01 to 7.5 x 10(8) cells/day. Most patients showed an immediate reincrease of virus load after the nadir. Changes in HIV p24 antigen paralleled HIV plasma RNA in p24 antigen-positive patients. beta 2-microglobulin decreased until day 7-15 in all but one case and rapidly reincreased to pretreatment values. CONCLUSIONS: The kinetics of virus and CD4+ T-cell turnover are uniformly rapid throughout a wide range of initial CD4+ T-cell counts. The magnitude of virus turnover varies considerably among individuals and appears to be inversely related to the initial CD4+ T-cell count. These data also argue for a rapid resumption of virus production and lymphocyte turnover during treatment.

Adult↗
PubMed1995

Investigations on autologous T-cells for adoptive immunotherapy of AIDS.

We report on the preclinical results of an immunotherapeutic approach of AIDS mediated by ex vivo propagated CD4+ and CD8+ T-cells. A mean yield of 6.23 x 10(9) lymphocytes, containing 1.82 x 10(9) CD4+, 3.23 x 10(9) CD8+ T-lymphocytes and 8.39 x 10(6) CD34+ peripheral blood progenitor cells (PBPC) were be obtained by continuous flow cytapheresis (CFC) in 15 asymptomatic HIV infected patients (CD4-count > 350/mm3). The CD4/CD8 ratio (mean: 0.53, SD: +/- 0.15) in the cell concentrates reflected the distribution of the circulating lymphocyte subsets in vivo. Absolute lymphocyte counts decreased at a mean of 404/microliter (25%) immediately after CFC but were replaced from the extravascular pool within one hour. Neither the CD4/CD8 ratio nor p24-antigen and neopterin levels did change significantly after cell separation. No alteration of the number of proviral DNA copies (1/10(3)-1/10(6)) could be detected in peripheral T-helper cells by semiquantitative PCR after lymphapheresis. Cells were cryopreserved in liquid nitrogen without substantial loss of viability or function. Ex vivo propagation of T-cells in a strictly autologous manner in the presence of PHA + IL-2 for 14d resulted in a 50-fold expansion rate (140-fold in healthy controls, p < 0.001). Viral replication could be controlled but not completely eliminated by cocultivation with autologous CD8+ T-lymphocytes as measured by limiting dilution nested PCR (NPCR). The expanded cells showed the typical phenotype of highly activated memory type T-lymphocytes (CD3+ CD45RO+ CD25+ HLA-DR+). The distribution of CD4+ and CD8+ T-cells did not reveal significant changes before and after culture indicating that both subsets were equally expanded. Functionally important membrane or intracellular epitopes which were found to be decreased in HIV infected subjects (CD7, CD55, CD59) before culture were reconstituted after ex vivo propagation of T-cells. The functional importance of the up-regulation of complement regulating epitopes (CD55, CD59) after culture could be proven by a significant inhibition of cytolysis of T-cells in the presence of autologous complement. The majority (75%) of expanded CD8+ T-cells stained positive with mAb TIA-1 which is directed to intracellular granules within cytotoxic T-cells. Furthermore, programmed cell death of expanded T-cells could be prevented by cocultivation with fibroblasts which are believed to secrete a cytokine pattern preventing activated T-cells from apoptosis after withdrawal of IL-2 and other stimuli.(ABSTRACT TRUNCATED AT 400 WORDS)

AIDS-Related Opportunistic Infections↗
PubMed1995

HIV-related non-Hodgkin's lymphoma among European AIDS patients. AIDS in Europe Study Group. AIDS in Europe Study Group.

The epidemiology of HIV associated non-Hodgkin's lymphoma (NHL) was investigated in 6550 European patients with AIDS. NHL was diagnosed in 3.5% of all patients at the time of the AIDS diagnosis. Although the probability of being diagnosed with NHL at AIDS diagnosis was significantly higher among intravenous drug users than among homosexual men, and was associated with increasing age, the observed incidences of NHL were more strikingly similar than any differences. The rate of developing NHL after a previous AIDS diagnosis was 2.4 per 100 patient years of follow-up, and remained constant during a 5-year follow-up period. While primary brain lymphomas comprised only 9% of NHL diagnosed at the time of AIDS, they comprised 38% of NHL diagnosed after AIDS (p < 0.001). The prognosis for patients with NHL at AIDS diagnosis was poor with a median survival of 5 months. A diagnosis of primary brain lymphoma was uniformly associated with a poor outcome. It is concluded that the probability of developing NHL in late stage HIV infection is lower than previously anticipated from the results of small studies on patients receiving long-term anti-retroviral therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Follicular dendritic cells retain HIV-1 particles on their plasma membrane, but are not productively infected in asymptomatic patients with follicular hyperplasia.

During HIV-1 infection, extensive alterations can be observed in the germinal centers (GCs) of lymphatic tissue. The initial hyperplasia of GCs is followed by disintegration and involution of these structures. The process is accompanied by progressive destruction of the network of follicular dendritic cells (FDCs). We investigated whether or not the destruction of GCs is caused by HIV-1 infection of FDCs in vivo. FDCs were purified by FACS or magnetic cell sorter (MACS) from enlarged lymph nodes (LNs) of four asymptomatic HIV-1-infected patients with persistent generalized lymphadenopathy. In situ hybridization demonstrated positive signals for HIV-1 RNA on the cell membrane of FDCs. Virus particles attached to the dendritic network could be demonstrated by electron microscopy, but budding was not seen. Furthermore, proviral DNA was detected by nested PCR (NPCR) in limiting dilution assays of FACS-purified FDCs (up to 1.0 x 10(4) cells) in only one cell fraction. In comparison, proviral DNA could be found in 5.0 x 10(3) to 2.5 x 10(5) FACS-purified Th cells obtained from peripheral blood and in 7.5 x 10(5) to 2.5 x 10(4) Th cells from LN of the same patients. In conclusion, FDCs retain HIV-1 particles on their cell membrane during HIV-1 infection, but the progressive destruction of FDC in vivo is probably not caused by a productive infection of FDCs with HIV-1.

Cell Membrane↗
PubMed1994

Recovery of T-lymphocytes for adoptive immunotherapy by lymphapheresis of HIV-infected patients without alterations of virological, immunological or clinical parameters.

We performed repeated continuous flow cytaphereses (CFC) on 13 asymptomatic HIV-1-infected patients to study the feasibility of cell separation procedures to recover high yields of peripheral blood T-lymphocytes for adoptive immunotherapy in HIV-infected patients and to determine immunological and virological alterations following such procedures. A mean yield of 6.23 x 10(9) lymphocytes could be obtained by each cytapheresis, containing 1.82 x 10(9) CD4+, 3.23 x 10(9) CD8+ T-lymphocytes and 8.39 x 10(6) CD34+ peripheral progenitor cells. The CD4/CD8 ratio (mean 0.53, SD +/- 0.15) in the cell samples reflected the distribution of the lymphocyte subsets in vivo. Absolute lymphocyte counts decreased at a mean of 404/mm3 (25%) immediately after CFC but were replaced from the extravascular pool within 1 h. The CD4/CD8 ratios, p24-antigenaemia, HLA-DR expression and neopterin levels did not change significantly after cell separation. No alteration of the number of T-cells with integrated proviral DNA copies (1/10(3) to 1/10(6)) could be detected in peripheral T-helper cells by PCR after lymphapheresis. We conclude that high yields of peripheral T-lymphocytes can be obtained by continuous flow lymphapheresis for cell-mediated immunotherapy, without deterioration of virological or immunological parameters in HIV-infected patients. The separated T-cells are fully replaced from extravascular pools after 1 h.

CD4-CD8 Ratio↗
PubMed1994

Vascular origin of Kaposi's sarcoma. Expression of leukocyte adhesion molecule-1, thrombomodulin, and tissue factor.

We studied seven cases of Kaposi's sarcomas (KS) obtained from patients with AIDS and one KS from a patient without HIV infection. Antigen expression was studied by immunocytochemistry and mRNA expression by in situ hybridisation. The markers tested were endothelial leukocyte adhesion molecule-1, thrombomodulin, and tissue factor. In all tumors (AIDS and non-AIDS associated) these markers reacted positive, indicating transcription and translation of these genes in KS. The synthesis and expression of tissue factor and thrombomodulin suggests that KS is a tumor that has tissue factor-mediated thrombin formation under the control of thrombomodulin. The expression of thrombomodulin and endothelial leukocyte adhesion molecule-1 provides evidence for the vascular origin of KS.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Optimizing follicular dendritic cell isolation by discontinuous gradient centrifugation and use of the magnetic cell sorter (MACS).

Follicular dendritic cells (FDC) contribute minimally to the total cell population of lymphatic tissue. In order to obtain higher numbers of viable FDC with only a small fraction of contaminating cells the following procedure was developed. Subsequent to the usual mechanical and enzymatical digestion of human tonsils, single cells were layered on top of a discontinuous bovine albumin gradient and centrifuged at 8500 x g. The suspension collected from the 1.052-1.030 interphase contained an average of 10.5% FDC. Next, the preparation was subjected to a new step involving separation of FDC previously treated with biotin-labelled KiM4 monoclonal antibody, raised against FDC, and attached via biotin-streptavidin bonding to streptavidin-conjugated paramagnetic beads. Purification on a magnetic cell sorter (MACS) yielded 3.3-10.1 x 10(6) cells with an average FDC content of 78.4%. The viability and morphology of the resulting FDC population was examined using trypan blue staining or electron microscopy. This technique will permit in vitro studies and long term cultures with FDC isolated from human lymphatic tissue.

Antibodies, Monoclonal↗
PubMed1992

[Clinical diagnosis and neuropathologic examination findings in 20 AIDS patients].

Disorders of the central nervous system (CNS) associated with HIV infections are becoming increasingly important in the area of clinical diagnosis and treatment of patients with AIDS. The aim of this retrospective analysis of 20 patients with AIDS who died in 1989 was to compare clinical diagnosis, neuroradiological findings and treatment with the results of neuropathological studies. The neuropathological examinations revealed primary CNS lymphoma (high-grade non-Hodgkin's lymphoma) in seven cases, cerebral toxoplasmosis in four cases, haemorrhagic infarction in three cases, cerebral cryptococcosis in three cases, and one case each of infiltration of the dura by a peripheral Burkitt's lymphoma, cytomegalovirus encephalitis and bacterial meningitis. A remarkably high percentage of CNS lymphomas with no distinct clinical or neuroradiological differentiation criteria were found in this study. On the basis of these data, we conclude that stereotactic biopsy and histological diagnosis should be recommended for patients with focal intracerebral lesions who fail to respond to suitable anti-parasitic treatment.

AIDS Dementia Complex↗
PubMedDate not supplied

Short term treatment of visceral leishmaniasis of the Old World with low dose interferon gamma and pentavalent antimony.

Eight adult patients with visceral leishmaniasis acquired in mediterranean countries were treated in a prospective study with a combined immunomodulating and antiparasitic regimen consisting of low-dose interferon-gamma (IFN-gamma) and pentavalent antimony. The clinical outcome, hematological and parasitological parameters, the duration of treatment and number of treatment cycles as well as the cumulative dose of pentavalent antimony applied, have been evaluated. The combined treatment led to complete resolution of symptoms and parasitological cure in all cases of visceral leishmaniasis without major side effects. Combined treatment resulted in a significant reduction of duration of treatment (19 vs. 31 days, p < 0.02) and cumulative dose of pentavalent antimony (11.67 vs. 19.30 g, p < 0.02) compared to historical controls (n = 6). No relapses occurred after a median follow-up of 9 months (range: 2-28 months). We conclude that combination therapy is tolerated well and is highly effective in patients with visceral leishmaniasis. The addition of IFN-gamma to standard therapy with pentavalent antimony may reduce the cumulative dose of antimonial drugs, shortens the treatment period and probably reduces the number of relapses.

Adult↗