Publications by authors named "Salum Lidenge"

Kaposi sarcoma (KS) is an AIDS-defining angio-proliferative malignancy, with the Kaposi sarcoma-associated herpes virus (KSHV) as its etiologic agent. Upon treatment with chemotherapy, a proportion of HIV-associated KS patients experience disease recurrence within a few months of completing treatment. We aimed at determining whether KSHV-specific adaptive immune responses were associated with KS recurrence upon complete remission.

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Seasonal coronaviruses (HCoVs) are known to contribute to cross-reactive antibody (Ab) responses against SARS-CoV-2. While these responses are predictable due to the high homology between SARS-CoV-2 and other CoVs, the impact of these responses on susceptibility to SARS-CoV-2 infection in cancer patients is unclear. To investigate the influence of prior HCoV infection on anti-SARS-CoV-2 Ab responses among COVID-19 asymptomatic individuals with cancer and controls without cancers, we utilized the VirScan technology in which phage immunoprecipitation and sequencing (PhIP-seq) of longitudinal plasma samples was performed to investigate high-resolution (i.

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Protein-level immunodominance patterns against Kaposi sarcoma-associated herpesvirus (KSHV), the aetiologic agent of Kaposi sarcoma (KS), have been revealed from serological probing of whole protein arrays, however, the epitopes that underlie these patterns have not been defined. We recently demonstrated the utility of phage display in high-resolution linear epitope mapping of the KSHV latency-associated nuclear antigen (LANA/ORF73). Here, a VirScan phage immunoprecipitation and sequencing approach, employing a library of 1,988 KSHV proteome-derived peptides, was used to quantify the breadth and magnitude of responses of 59 sub-Saharan African KS patients and 22 KSHV-infected asymptomatic individuals (ASY), and ultimately to support an application of machine-learning-based predictive modeling using the peptide-level responses.

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Background: Kaposi sarcoma (KS) is a neoplastic disease etiologically associated with infection by the Kaposi sarcoma-associated herpesvirus (KSHV). KS manifests primarily as cutaneous lesions in individuals due to either age (classical KS), HIV infection (epidemic KS), or tissue rejection preventatives in transplantation (iatrogenic KS) but can also occur in individuals, predominantly in sub-Saharan Africa (SSA), lacking any obvious immune suppression (endemic KS). The high endemicity of KSHV and human immunodeficiency virus-1 (HIV) co-infection in Africa results in KS being one of the top 5 cancers there.

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The ecancer Choosing Wisely conference was held for the second time in Africa in Dar es Salaam, Tanzania, from the 9th to 10th of February 2023. ecancer in collaboration with the Tanzania Oncology Society organised this conference which was attended by more than 150 local and international delegates. During the 2 days of the conference, more than ten speakers from different specialties in the field of oncology gave insights into Choosing Wisely in oncology.

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Purpose: In the past 20 years, the burden of anal cancer (AC) increased by 60% in the United States and over three-fold in Africa. Rates of AC have increased by 20× in people living with HIV and the highest (50×) in men with HIV who have sex with men. However, in sub-Saharan Africa (SSA) where HIV is endemic, data on clinicopathological characteristics and outcomes of patients with AC are lacking.

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The humoral antibody response against Kaposi sarcoma-associated herpesvirus (KSHV) in infected individuals has been characterized demonstrating the latency-associated nuclear antigen (LANA) as the most antigenic KSHV protein. Despite the antigenicity of the protein, specific LANA epitopes have not been systematically characterized. Here, we utilized a bacteriophage T7 library, which displays 56-amino acid KSHV LANA peptides with 28-amino acid overlap (VirScan), to define those epitopes in LANA targeted by antibodies from a cohort of 62 sub-Saharan African Kaposi sarcoma (KS) patients and 22 KSHV-infected asymptomatic controls.

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Objectives: To longitudinally compare SARS-CoV-2-specific T cell and humoral immune responses between convalescent individuals who are HIV-positive (HIV+) and HIV-negative (HIV-).

Methods: We conducted enzyme-linked immunospots to determine the SARS-CoV-2-specific T cell responses to spike and nucleocapsid, membrane protein, and other open reading frame proteins (NMO), whereas an immunofluorescence assay was used to determine the humoral responses. Participants were sampled at baseline and after 8 weeks of follow-up.

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Background: Despite the high COVID-19 morbidity and mortality rates across the world, the reported rates in sub-Saharan Africa (SSA), which has a higher burden of other infectious diseases and overwhelmed healthcare systems, remain relatively low. This study aims to better understand the potential factors that contribute to this phenomenon, especially among cancer patients who are considered as a high-risk group for developing severe COVID-19.

Methods: Plasma samples collected during the COVID-19 pandemic from SARS-CoV-2 unvaccinated cancer and potential blood donor populations were analyzed for SARS-CoV-2 (spike and nucleocapsid proteins) antibodies by an immunofluorescence assay.

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Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) virus is the cause of coronavirus disease 2019 (COVID-19). It has caused millions of infections and deaths globally over a 2-year period. Some populations including those living with HIV and/or cancer are reported to be at a higher risk of infection and severe disease.

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Article Synopsis
  • * Plasma samples were collected from 20 individuals exposed to or recovering from COVID-19, revealing that all subjects had SARS-CoV-2 specific IgG antibodies, with most showing high levels of nAb and strong ADCC activity.
  • * The results suggest that vaccines should not only assess neutralizing antibodies but also the ability to mediate ADCC, highlighting the need for a broader understanding of immune responses to SARS-CoV-2.
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Kaposi's sarcoma (KS) is an AIDS-defining malignancy that can improve or worsen with antiretroviral therapy (ART). We aimed at identifying clinical, HIV-related, and sociodemographic factors associated with either progression or nonprogression (regression or stable disease) of ART-treated HIV-associated KS in patients with limited cutaneous disease. We conducted a prospective cohort study of ART-treated HIV-associated KS cases.

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Objective: Significant morbidity and mortality have occurred in the USA, Europe, and Asia due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), whereas the numbers of infections and deaths in sub-Saharan Africa (SSA) have remained comparatively low. It has been hypothesized that exposure of the population in SSA to other coronaviruses prior to the COVID-19 pandemic resulted in some degree of cross-protection against SARS-CoV-2 infection and pathogenesis. We evaluated this hypothesis by comparing SARS-CoV-2 cross-reactive antibodies in pre-pandemic plasma samples collected from SSA and the USA.

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In sub-Saharan Africa, endemic Kaposi's sarcoma (EnKS) is still prevalent despite high incidence of epidemic Kaposi's sarcoma (EpKS) resulting from the on-going HIV-1 epidemic. While KSHV is clearly the etiologic agent of KS, the mechanisms underlying KS development are not fully understood. For example, HIV-1 co-infection and concomitant immune dysfunction have been associated with EpKS development.

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HIV-associated/epidemic Kaposi's sarcoma (EpKS) is an AIDS-defining angio-proliferative malignancy. It can be treated with antiretroviral therapy (ART) alone or with ART plus cytotoxic chemotherapy. ART-treated EpKS can either respond or worsen upon treatment.

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Kaposi's sarcoma-associated herpes virus (KSHV) is the etiologic agent for Kaposi's sarcoma (KS). The prognostic utility of KSHV and HIV-1 (human immunodeficiency virus) viremia as well as immunological parameters in clinical management of participants with KS is unclear. The objective of this study was to investigate viral and immunological parameters as predictors of KS treatment responses in participants with KS from sub-Saharan Africa (SSA).

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Despite the close association between Kaposi's sarcoma (KS) and immune dysfunction, it remains unclear whether tumor infiltrating immune cells (TIIC), by their absence, presence, or dysfunction, are mechanistically correlated with KS pathogenesis. Therefore, their potential capacity to serve as prognostic biomarkers of KS disease progression or control is unclear. Because epidemic-KS (EpKS) occurs with HIV-1 co-infection, it is particularly important to compare TIIC between EpKS and HIV-negative African endemic-KS (EnKS) to dissect the roles of HIV-1 and Kaposi Sarcoma-associated herpesvirus (KSHV) in KS pathogenesis.

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Objective: Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent for Kaposi's sarcoma (KS), one of the most common cancers in Tanzania. We have investigated KSHV prevalence and factors associated with KSHV infection in Tanzania.

Methods: This is a cross-sectional study of voluntary blood-donors from Dar es Salaam, Tanzania.

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Article Synopsis
  • Kaposi's sarcoma-associated herpesvirus (KSHV) is linked to Kaposi's sarcoma (KS) and is especially prevalent among people with HIV/AIDS in sub-Saharan Africa, where no preventative vaccine exists.
  • This study investigates the specific targets of KSHV neutralizing antibodies (nAbs) in individuals with KSHV, revealing that many recognize multiple viral glycoproteins and that response breadth varies by KS type.
  • The gH/gL complex of KSHV was identified as the main target for nAbs in 80% of KSHV-infected individuals, indicating its potential as a key focus for future vaccine development.
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Background: Kaposi sarcoma (KS)-associated herpesvirus (KSHV) is etiologically linked to all KS forms, but mechanisms underlying KS development are unclear. The incidence of KS in human immunodeficiency virus type 1-infected (HIV-1+) individuals implicates immune dysregulation; however, the lack of characterization of KSHV immune responses in endemic KS makes the role of HIV-1 unclear. The study objective was to investigate the HIV-1 and KSHV roles in viral nucleic acid detection, antibody responses, and cytokine responses in polymerase chain reaction-confirmed epidemic KS and endemic KS patients and non-cancer controls from sub-Saharan Africa.

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Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi's sarcoma (KS). It is endemic in a number of sub-Saharan African countries with infection rate of >50%. The high prevalence of HIV-1 coupled with late presentation of advanced cancer staging make KS the leading cancer in the region with poor prognosis and high mortality.

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Purpose: Cervical cancer is the leading cause of cancer-related morbidity and mortality in women in Tanzania. Any impact of the HIV/AIDS epidemic on cervical precancerous lesions and invasive cervical cancer has a significant implication, as for any public health concern, especially in an area such as the Morogoro region in Tanzania, which has one of the highest rates of cervical cancer in the world.

Methods: A comparative retrospective study was performed of 536 women screened for cervical cancer by visual inspection methods at the Morogoro Regional Referral Hospital over a period of 3 years; the women were grouped according to their HIV status.

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Background: In sub-Saharan Africa the availability of intensive care unit (ICU) services is limited by a variety of factors, including lack of financial resources, lack of available technology and well-trained staff. Tanzania has four main referral hospitals, located in zones so as to serve as tertiary level referral centers. All the referral hospitals have some ICU services, operating at varying levels of equipment and qualified staff.

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