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The monoclonal antibodies (MAbs) NCI05 and NCI09, isolated from a vaccinated macaque that was protected from multiple simian immunodeficiency virus (SIV) challenges, both target an overlapping, conformationally dynamic epitope in SIV envelope variable region 2 (V2). Here, we show that NCI05 recognizes a CH59-like coil/helical epitope, whereas NCI09 recognizes a ß-hairpin linear epitope. In vitro, NCI05 and, to a lesser extent, NCI09 mediate the killing of SIV-infected cells in a CD4-dependent manner. Compared to NCI05, NCI09 mediates higher titers of antibody-dependent cellular cytotoxicity (ADCC) to gp120-coated cells, as well as higher levels of trogocytosis, a monocyte function that contributes to immune evasion. We also found that passive administration of NCI05 or NCI09 to macaques did not affect the risk of SIVmac251 acquisition compared to controls, demonstrating that these anti-V2 antibodies alone are not protective. However, NCI05 but not NCI09 mucosal levels strongly correlated with delayed SIVmac251 acquisition, and functional and structural data suggest that NCI05 targets a transient state of the viral spike apex that is partially opened, compared to its prefusion-closed conformation. IMPORTANCE Studies suggest that the protection against SIV/simian-human immunodeficiency virus (SHIV) acquisition afforded by the SIV/HIV V1 deletion-containing envelope immunogens, delivered by the DNA/ALVAC vaccine platform, requires multiple innate and adaptive host responses. Anti-inflammatory macrophages and tolerogenic dendritic cells (DC-10), together with CD14+ efferocytes, are consistently found to correlate with a vaccine-induced decrease in the risk of SIV/SHIV acquisition. Similarly, V2-specific antibody responses mediating ADCC, Th1 and Th2 cells expressing no or low levels of CCR5, and envelope-specific NKp44+ cells producing interleukin 17 (IL-17) also are reproducible correlates of decreased risk of virus acquisition. We focused on the function and the antiviral potential of two monoclonal antibodies (NCI05 and NCI09) isolated from vaccinated animals that differ in antiviral function in vitro and recognize V2 in a linear (NCI09) or coil/helical (NCI05) conformation. We demonstrate that NCI05, but not NCI09, delays SIVmac251 acquisition, highlighting the complexity of antibody responses to V2.
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Anticorpos Monoclonais , Vírus da Imunodeficiência Símia , Proteínas Virais , Vírus da Imunodeficiência Símia/imunologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Monoclonais/metabolismo , Proteínas Virais/química , Proteínas Virais/imunologia , Epitopos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Estrutura Terciária de Proteína , Modelos Moleculares , Células CHO , Cricetulus , Animais , Macaca/imunologia , Macaca/virologia , Anticorpos Antivirais/sangueRESUMO
Adenovirus (Ad) is being explored for use in the prevention and treatment of a variety of infectious diseases and cancers. Ad with a deletion in early region 3 (ΔE3) provokes a stronger immune response than Ad with deletions in early regions 1 and E3 (ΔE1/ΔE3). The ΔE1/ΔE3 Ads are more popular because they can carry a larger transgene and because of the deleted E1 (E1A and E1B), are perceived safer for clinical use. Ad with a deletion in E1B55K (ΔE1B55K) has been in phase III clinical trials for use in cancer therapy in the US and has been approved for use in head and neck tumor therapy in China, demonstrating that Ad containing E1A are safe for clinical use. We have shown previously that ΔE1B55K Ad, even while promoting lower levels of an inserted transgene, promoted similar levels of transgene-specific immune responses as a ΔE3 Ad. Products of the Ad early region 4 (E4) limit the ability of cells to mount an innate immune response. Using this knowledge, we deleted the Ad E4 open reading frames 1-4 (E4orf1-4) from the ΔE1B55K Ad. Here, we show that innate cytokine network genes are elevated in the ΔE4 Ad-infected cells beyond that of ΔE3 Ad-infected cells. Further, in immunized mice the IgG2a subclass was favored as was the IgG1 subclass in immunized nonhuman primates. Thus, Ad E4 impacts immune responses in cells, in immunized mice, and immunized nonhuman primates. These Ad may offer advantages that are beneficial for clinical use.Importance: Adenovirus (Ad) is being explored for use in the prevention and treatment of a variety of infectious diseases and cancers. Here we provide evidence in cells, mice, and nonhuman primates supporting the notion that Ad early gene-products limit specific immune responses. Ad constructed with deletions in early genes and expressing HIV envelope protein was shown to induce greater HIV-specific cellular immune responses and higher titer antibodies compared to the parental Ad with the early genes. In addition to eliciting enhanced immunity, the deleted Ad possesses more space for insertion of additional or larger transgenes needed for targeting other infectious agents or cancers.
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The recombinant Canarypox ALVAC-HIV/gp120/alum vaccine regimen was the first to significantly decrease the risk of HIV acquisition in humans, with equal effectiveness in both males and females. Similarly, an equivalent SIV-based ALVAC vaccine regimen decreased the risk of virus acquisition in Indian rhesus macaques of both sexes following intrarectal exposure to low doses of SIVmac251. Here, we demonstrate that the ALVAC-SIV/gp120/alum vaccine is also efficacious in female Chinese rhesus macaques following intravaginal exposure to low doses of SIVmac251 and we confirm that CD14+ classical monocytes are a strong correlate of decreased risk of virus acquisition. Furthermore, we demonstrate that the frequency of CD14+ cells and/or their gene expression correlates with blood Type 1 CD4+ T helper cells, α4ß7+ plasmablasts, and vaginal cytocidal NKG2A+ cells. To better understand the correlate of protection, we contrasted the ALVAC-SIV vaccine with a NYVAC-based SIV/gp120 regimen that used the identical immunogen. We found that NYVAC-SIV induced higher immune activation via CD4+Ki67+CD38+ and CD4+Ki67+α4ß7+ T cells, higher SIV envelope-specific IFN-γ producing cells, equivalent ADCC, and did not decrease the risk of SIVmac251 acquisition. Using the systems biology approach, we demonstrate that specific expression profiles of plasmablasts, NKG2A+ cells, and monocytes elicited by the ALVAC-based regimen correlated with decreased risk of virus acquisition.
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Células Matadoras Naturais/imunologia , Monócitos/imunologia , Vacinas contra a SAIDS/imunologia , Vírus da Imunodeficiência Símia/imunologia , Células Th1/imunologia , Vacinação , Vagina/imunologia , Vacinas Virais/imunologia , Animais , Feminino , Células Matadoras Naturais/patologia , Macaca mulatta , Monócitos/patologia , Células Th1/patologiaRESUMO
Because of microbicide noncompliance and lack of a durable, highly effective vaccine, a combined approach might improve HIV prophylaxis. We tested whether a vaccine-microbicide combination would enhance protection against SIV infection in rhesus macaques. Four macaque groups included vaccine only, vaccine-microbicide, microbicide only, and controls. Vaccine groups were primed twice mucosally with replicating adenovirus type 5 host range mutant SIV env/rev, gag, and nef recombinants and boosted twice i.m. with SIV gp120 proteins in alum. Controls and the microbicide-only group received adenovirus type 5 host range mutant empty vector and alum. The microbicide was SAMT-247, a 2-mercaptobenzamide thioester that targets the viral nucleocapsid protein NCp7, causing zinc ejection and preventing RNA encapsidation. Following vaccination, macaques were challenged intravaginally with repeated weekly low doses of SIVmac251 administered 3 h after application of 0.8% SAMT-247 gel (vaccine-microbicide and microbicide groups) or placebo gel (vaccine-only and control groups). The microbicide-only group exhibited potent protection; 10 of 12 macaques remained uninfected following 15 SIV challenges. The vaccine-only group developed strong mucosal and systemic humoral and cellular immunity but did not exhibit delayed acquisition compared with adjuvant controls. However, the vaccine-microbicide group exhibited significant acquisition delay compared with both control and vaccine-only groups, indicating further exploration of the combination strategy is warranted. Impaired protection in the vaccine-microbicide group compared with the microbicide-only group was not attributed to a vaccine-induced increase in SIV target cells. Possible Ab-dependent enhancement will be further investigated. The potent protection provided by SAMT-247 encourages its movement into human clinical trials.
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Anti-Infecciosos/farmacologia , Benzamidas/farmacologia , Macaca mulatta/imunologia , Vacinas contra a SAIDS/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Adenoviridae/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antivirais/imunologia , Células Cultivadas , Feminino , Produtos do Gene gag/imunologia , Vetores Genéticos/imunologia , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Imunidade Humoral/efeitos dos fármacos , Imunidade Humoral/imunologia , Macaca mulatta/virologia , Glicoproteínas de Membrana/imunologia , Projetos Piloto , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/imunologia , Proteínas do Envelope Viral/imunologiaRESUMO
An efficacious human immunodeficiency virus (HIV) vaccine will likely require induction of both mucosal and systemic immune responses. We compared the immunogenicity and protective efficacy of two mucosal/systemic vaccine regimens and investigated their effects on the rectal microbiome. Rhesus macaques were primed twice mucosally with replication-competent adenovirus type 5 host range mutant (Ad5hr)-simian immunodeficiency virus (SIV) recombinants and boosted twice intramuscularly with ALVAC-SIV recombinant plus SIV gp120 protein or with DNA for SIV genes and rhesus interleukin-12 plus SIV gp120 protein. Controls received empty Ad5hr vector and alum adjuvant only. Both regimens elicited strong, comparable mucosal and systemic cellular and humoral immunity. Prevaccination rectal microbiomes of males and females differed and significantly changed over the course of immunization, most strongly in females after Ad5hr immunizations. Following repeated low-dose intrarectal SIV challenges, both vaccine groups exhibited modestly but significantly reduced acute viremia. Male and female controls exhibited similar acute viral loads; however, vaccinated females, but not males, exhibited lower levels of acute viremia, compared to same-sex controls. Few differences in adaptive immune responses were observed between the sexes. Striking differences in correlations of the rectal microbiome of males and females with acute viremia and immune responses associated with protection were seen and point to effects of the microbiome on vaccine-induced immunity and viremia control. Our study clearly demonstrates direct effects of a mucosal SIV vaccine regimen on the rectal microbiome and validates our previously reported SIV vaccine-induced sex bias. Sex and the microbiome are critical factors that should not be overlooked in vaccine design and evaluation.IMPORTANCE Differences in HIV pathogenesis between males and females, including immunity postinfection, have been well documented, as have steroid hormone effects on the microbiome, which is known to influence mucosal immune responses. Few studies have applied this knowledge to vaccine trials. We investigated two SIV vaccine regimens combining mucosal priming immunizations and systemic protein boosting. We again report a vaccine-induced sex bias, with female rhesus macaques but not males displaying significantly reduced acute viremia. The vaccine regimens, especially the mucosal primes, significantly altered the rectal microbiome. The greatest effects were in females. Striking differences between female and male macaques in correlations of prevalent rectal bacteria with viral loads and potentially protective immune responses were observed. Effects of the microbiome on vaccine-induced immunity and viremia control require further study by microbiome transfer. However, the findings presented highlight the critical importance of considering effects of sex and the microbiome in vaccine design and evaluation.
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Imunização Secundária/métodos , Macaca mulatta/imunologia , Microbiota/efeitos dos fármacos , Reto/microbiologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Viremia/imunologia , Vacinas contra a AIDS/imunologia , Adenoviridae/genética , Animais , Feminino , Imunidade Humoral , Imunidade nas Mucosas , Masculino , Microbiota/fisiologia , Reto/imunologia , Vacinas contra a SAIDS/imunologiaRESUMO
NK cells are essential for controlling viral infections. We investigated NK cell and innate lymphoid cell (ILC) dynamics and function in rhesus macaque rectal tissue and blood following mucosal priming with replicating adenovirus (Ad)-SIV recombinants, systemic boosting with SIV envelope protein, and subsequent repeated low-dose intravaginal SIV exposures. Mucosal memory-like NK and ILC subsets in rectal and vaginal tissues of chronically infected macaques were also evaluated. No differences in NK cell or ILC frequencies or cytokine production were seen between vaccinated and Ad-empty/alum controls, suggesting responses were due to the Ad-vector and alum vaccine components. Mucosal NKp44+ ILCs increased postvaccination and returned to prelevels postinfection. The vaccine regimen induced mucosal SIV-specific Ab, which mediated Ab-dependent cellular cytotoxicity and was correlated with mucosal NKp44+CD16+ ILCs. Postvaccination NKp44+ and NKp44+IL-17+ ILC frequencies were associated with delayed SIV acquisition and decreased viremia. In chronically SIV-infected animals, NKp44+ ILCs negatively correlated with viral load, further suggesting a protective effect, whereas, NKG2A- NKp44- double-negative ILCs positively correlated with viral load, indicating a pathogenic role. No such associations of circulating NK cells were seen. Δγ NK cells in mucosal tissues of chronically infected animals exhibited impaired cytokine production compared with non-Δγ NK cells but responded to anti-gp120 Ab and Gag peptides, whereas non-Δγ NK cells did not. Mucosal Δγ NKp44+ and Δγ DN cells were similarly associated with protection and disease progression, respectively. Thus, the data suggest NKp44+ ILCs and Δγ cells contribute to SIV infection outcomes. Vaccines that promote mucosal NKp44+ and suppress double-negative ILCs are likely desirable.
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Subpopulações de Linfócitos/imunologia , Receptor 2 Desencadeador da Citotoxicidade Natural/análise , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Animais , Citotoxicidade Celular Dependente de Anticorpos , Feminino , Imunidade Inata , Imunidade nas Mucosas , Células Matadoras Naturais/imunologia , Macaca mulatta , Reto/imunologia , Vacinas contra a SAIDS/imunologia , Vacinação , Vagina/imunologiaRESUMO
Follicular CD8+ T (fCD8) cells reside within B cell follicles and are thought to be immune-privileged sites of HIV/SIV infection. We have observed comparable levels of fCD8 cells between chronically SIV-infected rhesus macaques with low viral loads (LVL) and high viral loads (HVL), raising the question concerning their contribution to viremia control. In this study, we sought to clarify the role of SIV-specific fCD8 cells in lymph nodes during the course of SIV infection in rhesus macaques. We observed that fCD8 cells, T follicular helper (Tfh) cells, and T follicular regulatory cells (Tfreg) were all elevated in chronic SIV infection. fCD8 cells of LVL animals tended to express more Gag-specific granzyme B and exhibited significantly greater killing than did HVL animals, and their cell frequencies were negatively correlated with viremia, suggesting a role in viremia control. Env- and Gag-specific IL-21+ Tfh of LVL but not HVL macaques negatively correlated with viral load, suggesting better provision of T cell help to fCD8 cells. Tfreg positively correlated with fCD8 cells in LVL animals and negatively correlated with viremia, suggesting a potential benefit of Tfreg via suppression of chronic inflammation. In contrast, in HVL macaques, Tfreg and fCD8 cell frequencies tended to be negatively correlated, and a positive correlation was seen between Tfreg number and viremia, suggesting possible dysfunction and suppression of an effective fCD8 cell immune response. Our data suggest that control of virus-infected cells in B cell follicles not only depends on fCD8 cell cytotoxicity but also on complex fCD8 cell associations with Tfh cells and Tfreg.
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Linfócitos T CD8-Positivos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Viremia/imunologia , Animais , Linfócitos B/imunologia , Linfócitos B/virologia , Linfócitos T CD8-Positivos/virologia , Feminino , Inflamação/imunologia , Inflamação/virologia , Interleucinas/imunologia , Linfonodos/imunologia , Linfonodos/virologia , Macaca mulatta , Masculino , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Linfócitos T Auxiliares-Indutores/virologia , Linfócitos T Reguladores/virologia , Carga Viral/imunologia , Viremia/virologiaRESUMO
Neutrophils are the most abundant leukocyte and play a critical role in the initial response to an Ag. Recently, their ability to contribute to adaptive immunity has been highlighted. We evaluated the ability of neutrophils from blood to contribute to the adaptive immune response in a preclinical rhesus macaque SIV vaccine trial. Replication-competent adenovirus-SIV recombinants induced neutrophil activation, B cell help markers, and enhanced ability to generate reactive oxygen species. Boosting with SIV vaccines (adjuvant together with ALVAC or DNA plus envelope protein) elicited significant neutrophil responses. Serum cytokine and chemokine levels induced correlated with the frequency of neutrophil subsets expressing IL-21, myeloperoxidase, and CD64. Post-SIV infection, neutrophils exhibited dysfunction, both phenotypically and functionally. B cells from protected and infected macaques cocultured with autologous polymorphonuclear cells, consisting primarily of neutrophils, were activated, underwent class switching, and produced Abs. This B cell help was not aided by addition of IL-10 and was largely contact dependent. Numerous genes associated with inflammation, Ab production, and chemotaxis were upregulated in the cocultured B cells. We conclude that immune stimulation by vaccination or antigenic exposure imparts a greater ability of neutrophils to contribute to the adaptive immune response. Harnessing this granulocytic response has the potential to improve vaccine efficacy.
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Vacinas contra a AIDS/imunologia , Linfócitos B/imunologia , Células Sanguíneas/imunologia , Infecções por HIV/imunologia , HIV/imunologia , Neutrófilos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/genética , Imunidade Adaptativa , Adenoviridae/genética , Animais , Anticorpos Antivirais/biossíntese , Formação de Anticorpos , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Humanos , Imunização Secundária , Interleucinas/metabolismo , Ativação Linfocitária , Macaca mulatta , Ativação de Neutrófilo , Neutrófilos/patologia , Comunicação Parácrina , Peroxidase/metabolismo , Receptores de IgG/metabolismo , VacinaçãoRESUMO
HLA-B*52:01-C*12:02, which is the most abundant haplotype in Japan, has a protective effect on disease progression in HIV-1-infected Japanese individuals, whereas HLA-B*57 and -B*27 protective alleles are very rare in Japan. A previous study on HLA-associated polymorphisms demonstrated that the number of HLA-B*52:01-associated mutations at four Pol positions was inversely correlated with plasma viral load (pVL) in HLA-B*52:01-negative individuals, suggesting that the transmission of HIV-1 with these mutations could modulate the pVL in the population. However, it remains unknown whether these mutations were selected by HLA-B*52:01-restricted CTLs and also reduced viral fitness. In this study, we identified two HLA-B*52:01-restricted and one HLA-C*12:02-restricted novel cytotoxic T-lymphocyte (CTL) epitopes in Pol. Analysis using CTLs specific for these three epitopes demonstrated that these CTLs failed to recognize mutant epitopes or more weakly recognized cells infected with mutant viruses than wild-type virus, supporting the idea that these mutations were selected by the HLA-B*52:01- or HLA-C*12:02-restricted T cells. We further showed that these mutations reduced viral fitness, although the effect of each mutation was weak. The present study demonstrated that the accumulation of these Pol mutations selected by HLA-B*52:01- or HLA-C*12:02-restricted CTLs impaired viral replication capacity and thus reduced the pVL. The fitness cost imposed by the mutations partially accounted for the effect of the HLA-B*52:01-C*12:02 haplotype on clinical outcome, together with the effect of HLA-B*52:01-restricted CTLs on viral replication, which had been previously demonstrated. IMPORTANCE: Numerous population-based studies identified HLA-associated HIV-1 mutations to predict HIV-1 escape mutations from cytotoxic T lymphocytes (CTLs). However, the majority of these HLA-associated mutations have not been identified as CTL escape mutations. Our previous population-based study showed that five HLA-B*52:01-associated mutations at four Pol positions were inversely correlated with the plasma viral load in HLA-B*52:01-negative Japanese individuals. In the present study, we demonstrated that these mutations were indeed selected by CTLs specific for novel B*52:01- and C*12:02-restricted epitopes and that the accumulation of these mutations reduced the viral fitness in vitro This study elucidated the mechanism by which the accumulation of these CTL escape mutations contributed to the protective effect of the HLA-B*52:01-HLA-C*12:02 haplotype on disease progression in HIV-1-infected Japanese individuals.
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Aptidão Genética , Antígenos HLA-B/imunologia , Haplótipos , Mutação , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Carga Viral , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Produtos do Gene pol do Vírus da Imunodeficiência Humana/imunologia , Alelos , Sequência de Aminoácidos , Epitopos/química , Epitopos/imunologia , Genótipo , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Replicação ViralRESUMO
UNLABELLED: The effect of antiretroviral drug resistance mutations on cytotoxic T lymphocyte (CTL) recognition has been analyzed in HIV-1 subtype B infections, but it remains unclear in infections by other HIV-1 subtypes that are epidemic in countries where antiretroviral drugs are not effectively used. We investigated the effect of nonnucleoside reverse transcriptase (RT) inhibitor (NNRTI)-resistance mutations (Y181C, Y181I, and Y181V) on epitope recognition by CTLs specific for 3 different HIV-1 epitopes (HLA-A*02:01-restricted IV10, HLA-B*35:01-restricted NY9, and HLA-C*12:02-restricted KY9) in subtype B and subtype A/E infections and the accumulation of these mutations in treatment-naive Japanese and Vietnamese. These NNRTI-resistance mutations critically affected NY9-specific and KY9-specific T cell responses in the subtype B infections, whereas they showed a different effect on IV10-specific T cell responses among the subtype B-infected individuals. These mutations affected IV10-specific T cell responses but weakly affected NY9-specific T cell responses in the subtype A/E infections. The substitution at position 3 of NY9 epitope which was found in the subtype A/E virus differently influenced the peptide binding to HLA-B*35:01, suggesting that the differences in peptide binding may result in the differences in T cell recognition between the subtype B virus and A/E virus infections. The Y181C mutation was found to be accumulating in treatment-naive Vietnamese infected with the subtype A/E virus. The present study demonstrated different effects of NNRTI-resistance RT181 mutations on CTL responses between the 2 subtype infections. The Y181C mutation may influence HIV-1 control by the CTLs in Vietnam, since this mutation has been accumulating in treatment-naive Vietnamese. IMPORTANCE: Antiretroviral therapy leads to the emergence of drug-resistant HIV-1, resulting in virological and clinical failures. Though HIV-1-specific CTLs play a critical role in HIV-1 infection, some of drug resistance mutations located in CTL epitopes are known to affect HIV-1-specific CTL responses. Nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistance RT181 mutations are frequently observed in patients treated with NNRTIs. Such drug resistance mutations may have an influence on immune control by HIV-1-specific CTLs, especially in countries where antiretroviral drugs are not effectively used. We here investigated the effect of three NNRTI-resistance RT181 mutations on immune responses by HIV-1-specific CTLs and the recent accumulation of these mutations in treatment-naive Vietnamese infected with HIV-1 subtype A/E virus. RT181 mutations affected CTL recognition in both subtype A/E and B infections, while the RT Y181C mutation has been accumulating in treatment-naive Vietnamese. The results suggest that the Y181C mutation may influence HIV-1 control by CTLs in Vietnam.
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Farmacorresistência Viral , Transcriptase Reversa do HIV/genética , Transcriptase Reversa do HIV/imunologia , Mutação de Sentido Incorreto , Nucleosídeos/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Linfócitos T Citotóxicos/imunologia , Epitopos/genética , Epitopos/imunologia , Genótipo , Infecções por HIV/virologia , Transcriptase Reversa do HIV/classificação , Humanos , Japão , Proteínas Mutantes/genética , Proteínas Mutantes/imunologia , Nucleosídeos/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , VietnãRESUMO
The transient depletion of monocytes alone prior to exposure of macaques to HTLV-1 enhances both HTLV-1WT (wild type) and HTLV-1p12KO (Orf-1 knockout) infectivity, but seroconversion to either virus is not sustained over time, suggesting a progressive decrease in virus expression. These results raise the hypotheses that either HTLV-1 persistence depends on a monocyte reservoir or monocyte depletion provides a transient immune evasion benefit. To test these hypotheses, we simultaneously depleted NK cells, CD8+ T cells, and monocytes (triple depletion) prior to exposure to HTLV-1WT or HTLV-1p12KO. Remarkably, triple depletion resulted in exacerbation of infection by both viruses and complete rescue of HTLV-1p12KO infectivity. Following triple depletion, we observed rapid and sustained seroconversion, high titers of antibodies against HTLV-1 p24Gag, and frequent detection of viral DNA in the blood and tissues of all animals when compared with depletion of only CD8+ and NK cells, or monocytes alone. The infection of macaques with HTLV-1WT or HTLV-1p12KO was associated with higher plasma levels of IL-10 after 21 weeks, while IL-6, IFN-γ, IL-18, and IL-1ß were only elevated in animals infected with HTLV-1WT. The repeat depletion of monocytes, NK, and CD8+ cells seven months following the first exposure to HTLV-1 did not further exacerbate viral replication. These results underscore the contribution of monocytes in orchestrating anti-viral immunity. Indeed, the absence of orf-1 expression was fully compensated by the simultaneous depletion of CD8+ T cells, NK cells, and monocytes, underlining the primary role of orf-1 in hijacking host immunity.
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Globally, childhood cancer, particularly non-Hodgkin lymphomas (NHLs), is a prevalent concern. However, the difficulty becomes even more distressing in lower-middle-income nations such as Bangladesh. The insufficiency of research, resources, inadequate guidelines, expensive treatment costs, and specialized knowledge exacerbate the challenges associated with the treatment of certain types of cancers. Our investigation looked extensively into the circumstances prevailing in Bangladesh, with the objective of providing a comprehensive overview of the current status and approaches to managing NHL in the country. Through this work, our intention was to illuminate the domains that require immediate focus and assistance. To get insight into the present state of NHL in Bangladesh, our analysis focused on a selection of seven research articles and two case reports published between 2018 and 2023. In order to ensure the integrity and consistency of our review, we conducted a detailed selection procedure, employing the systematic PRISMA review methodology. From a pool of 294 papers, we selected the ones that met our predetermined criteria. These papers were sourced from reputable academic databases, such as Google Scholar and PubMed. The findings of our study indicate a higher prevalence of NHL among children in Bangladesh compared to Hodgkin lymphoma (HL). Additionally, this phenomenon exhibits a higher prevalence among male individuals. Our study revealed that in Bangladesh, there is a lack of a dedicated guideline or research center specifically focused on NHL. Additionally, the number of research centers and research dedicated to cancer treatment as a whole is limited. Our research aims to offer a complete analysis of NHL in the context of Bangladesh, with the intention of offering valuable guidance to healthcare professionals and policymakers. The utilization of our research outcomes has the potential to enhance patient care, facilitate the development of more effective clinical protocols, and promote greater accessibility and affordability of therapies. This has the potential to provide improved cancer care not only in Bangladesh but also in other comparable contexts worldwide.
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Introduction: An efficacious HIV vaccine will need to elicit a complex package of innate, humoral, and cellular immune responses. This complex package of responses to vaccine candidates has been studied and yielded important results, yet it has been a recurring challenge to determine the magnitude and protective effect of specific in vivo immune responses in isolation. We therefore designed a single, viral-spike-apical, epitope-focused V2 loop immunogen to reveal individual vaccine-elicited immune factors that contribute to protection against HIV/SIV. Method: We generated a novel vaccine by incorporating the V2 loop B-cell epitope in the cholera toxin B (CTB) scaffold and compared two new immunization regimens to a historically protective 'standard' vaccine regimen (SVR) consisting of 2xDNA prime boosted with 2xALVAC-SIV and 1xΔV1gp120. We immunized a cohort of macaques with 5xCTB-V2c vaccine+alum intramuscularly simultaneously with topical intrarectal vaccination of CTB-V2c vaccine without alum (5xCTB-V2/alum). In a second group, we tested a modified version of the SVR consisting of 2xDNA prime and boosted with 1xALVAC-SIV and 2xALVAC-SIV+CTB-V2/alum, (DA/CTB-V2c/alum). Results: In the absence of any other anti-viral antibodies, V2c epitope was highly immunogenic when incorporated in the CTB scaffold and generated highly functional anti-V2c antibodies in the vaccinated animals. 5xCTB-V2c/alum vaccination mediated non-neutralizing ADCC activity and efferocytosis, but produced low avidity, trogocytosis, and no neutralization of tier 1 virus. Furthermore, DA/CTB-V2c/alum vaccination also generated lower total ADCC activity, avidity, and neutralization compared to the SVR. These data suggest that the ΔV1gp120 boost in the SVR yielded more favorable immune responses than its CTB-V2c counterpart. Vaccination with the SVR generates CCR5- α4ß7+CD4+ Th1, Th2, and Th17 cells, which are less likely to be infected by SIV/HIV and likely contributed to the protection afforded in this regimen. The 5xCTB-V2c/alum regimen likewise elicited higher circulating CCR5- α4ß7+ CD4+ T cells and mucosal α4ß7+ CD4+ T cells compared to the DA/CTB-V2c/alum regimen, whereas the first cell type was associated with reduced risk of viral acquisition. Conclusion: Taken together, these data suggest that individual viral spike B-cell epitopes can be highly immunogenic and functional as isolated immunogens, although they might not be sufficient on their own to provide full protection against HIV/SIV infection.
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Vacinas contra a AIDS , Infecções por HIV , Animais , Toxina da Cólera , Epitopos , Macaca mulatta , Infecções por HIV/prevenção & controleRESUMO
The human immunodeficiency virus epidemic continues in sub-Saharan Africa, and particularly affects adolescent girls and women who have limited access to antiretroviral therapy. Here we report that the risk of vaginal simian immunodeficiency virus (SIV)mac251 acquisition is reduced by more than 90% using a combination of a vaccine comprising V1-deleted (V2 enhanced) SIV envelope immunogens with topical treatment of the zinc-finger inhibitor SAMT-247. Following 14 weekly intravaginal exposures to the highly pathogenic SIVmac251, 80% of a cohort of 20 macaques vaccinated and treated with SAMT-247 remained uninfected. In an arm of 18 vaccinated-only animals without microbicide, 40% of macaques remained uninfected. The combined SAMT-247/vaccine regimen was significantly more effective than vaccination alone. By analysing immune correlates of protection, we show that, by increasing zinc availability, SAMT-247 increases natural killer cytotoxicity and monocyte efferocytosis, and decreases T-cell activation to augment vaccine-induced protection.
Assuntos
Anti-Infecciosos , Vacinas contra a SAIDS , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Vacinas , Animais , Humanos , Feminino , Adolescente , Macaca mulattaRESUMO
At the heart of the DNA/ALVAC/gp120/alum vaccine's efficacy in the absence of neutralizing antibodies is a delicate balance of pro- and anti-inflammatory immune responses that effectively decreases the risk of SIVmac251 acquisition in macaques. Vaccine efficacy is linked to antibodies recognizing the V2 helical conformation, DC-10 tolerogenic dendritic cells eliciting the clearance of apoptotic cells via efferocytosis, and CCR5 downregulation on vaccine-induced gut homing CD4+ cells. RAS activation is also linked to vaccine efficacy, which prompted the testing of IGF-1, a potent inducer of RAS activation with vaccination. We found that IGF-1 changed the hierarchy of V1/V2 epitope recognition and decreased both ADCC specific for helical V2 and efferocytosis. Remarkably, IGF-1 also reduced the expression of CCR5 on vaccine-induced CD4+ gut-homing T-cells, compensating for its negative effect on ADCC and efferocytosis and resulting in equivalent vaccine efficacy (71% with IGF-1 and 69% without).
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The development of an effective vaccine to protect against HIV acquisition will be greatly bolstered by in-depth understanding of the innate and adaptive responses to vaccination. We report here that the efficacy of DNA/ALVAC/gp120/alum vaccines, based on V2-specific antibodies mediating apoptosis of infected cells (V2-ADCC), is complemented by efferocytosis, a cyclic AMP (cAMP)-dependent antiphlogistic engulfment of apoptotic cells by CD14+ monocytes. Central to vaccine efficacy is the engagement of the CCL2/CCR2 axis and tolerogenic dendritic cells producing IL-10 (DC-10). Epigenetic reprogramming in CD14+ cells of the cyclic AMP/CREB pathway and increased systemic levels of miRNA-139-5p, a negative regulator of expression of the cAMP-specific phosphodiesterase PDE4D, correlated with vaccine efficacy. These data posit that efferocytosis, through the prompt and effective removal of apoptotic infected cells, contributes to vaccine efficacy by decreasing inflammation and maintaining tissue homeostasis.
Assuntos
Vacinas contra a AIDS , Infecções por HIV , Feminino , Animais , Eficácia de Vacinas , Macaca mulatta , Vacinação , Citotoxicidade Celular Dependente de Anticorpos , Anticorpos Anti-HIV , Infecções por HIV/prevenção & controle , Proteína gp120 do Envelope de HIV/genéticaRESUMO
Human T cell leukemia virus type 1 (HTLV-1) persists in the host despite a vigorous immune response that includes cytotoxic T cells (CTL) and natural killer (NK) cells, suggesting the virus has developed effective mechanisms to counteract host immune surveillance. We recently showed that in vitro treatment of HTLV-1-infected cells with the drug pomalidomide (Pom) increases surface expression of MHC-I, ICAM-1, and B7-2, and significantly increases the susceptibility of HTLV-1-infected cells to NK and CTL killing, which is dependent on viral orf-I expression. We reasoned that by restoring cell surface expression of these molecules, Pom treatment has the potential to reduce virus burden by rendering infected cells susceptible to NK and CTL killing. We used the rhesus macaque model to determine if Pom treatment of infected individuals activates the host immune system and allows recognition and clearance of HTLV-1-infected cells. We administered Pom (0.2 mg/kg) orally to four HTLV-1-infected macaques over a 24 day period and collected blood, urine, and bone marrow samples throughout the study. Pom treatment caused immune activation in all four animals and a marked increase in proliferating CD4+, CD8+, and NK cells as measured by Ki-67+ cells. Activation markers HLA-DR, CD11b, and CD69 also increased during treatment. While we detected an increased frequency of cells with a memory CD8+ phenotype, we also found an increased frequency of cells with a Treg-like phenotype. Concomitant with immune activation, the frequency of detection of viral DNA and the HTLV-1-specific humoral response increased as well. In 3 of 4 animals, Pom treatment resulted in increased antibodies to HTLV-1 antigens as measured by western blot and p24Gag ELISA. Consistent with Pom inducing immune and HTLV-1 activation, we measured elevated leukotrienes LTB4 and LTE4 in the urine of all animals. Despite an increase in plasma LTB4, no significant changes in plasma cytokine/chemokine levels were detected. In all cases, however, cellular populations, LTB4, and LTE4 decreased to baseline or lower levels 2 weeks after cessation of treatment. These results indicated that Pom treatment induces a transient HTLV-1-specific immune activation in infected individuals, but also suggest Pom may not be effective as a single-agent therapeutic.
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As demonstrated by the recent COVID pandemic, vaccines can reduce the burden arising from infectious agents. Adenoviruses (Ads) with deletion of the early region 1B55K (ΔE1B Ad) are currently being explored for use in vaccine delivery. ΔE1B Ads are different from Ads with deletions in early region 1 and early region 3 (ΔE1/E3) used in most Ad vaccine vectors in that they contain the Ad early region 1A (E1A), and therefore the ability to replicate. Common to almost all Ads that are being explored for clinical use is the Ad early region 4 (E4). Among the E4 genes is open reading frame 1 (E4orf1), which mediates signals through the PI3-kinase/Akt pathway that is known to modulate immune responses. This suggests that E4orf1 might also modulate immune responses, although it has remained unexplored in ΔE1B Ad. Here, we show that cells infected with an E1B55K and E4orf1-deleted (ΔE41) Ad exhibited reduced levels of phosphorylated Akt (Ser473 and Thr308)) and expressed different intrinsic innate immune cytokines from those induced in cells infected with an E4orf1-containing, ΔE1B parental Ad that exhibited elevated levels of phosphorylated Akt. Rhesus macaques immunized with a ΔE41 Ad that expressed rhFLSC (HIV-1BaL gp120 linked to rhesus CD4 D1 and D2), exhibited higher levels of rhFLSC-specific interferon γ-producing memory T-cells, higher titers of rhFLSC-specific IgG1 binding antibody in serum, and antibodies able to mediate antibody-dependent cellular cytotoxicity (ADCC) with greater killing capacity than the ΔE1B Ad. Therefore, E4orf1, perhaps by acting through the PI3-kinase/Akt pathway, limits intrinsic innate and system-wide adaptive immune responses that are important for improved ΔE1B Ad-based vaccines.
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T follicular helper (TFH) cells are pivotal in lymph node (LN) germinal center (GC) B cell affinity maturation. Circulating CXCR5+ CD4+ T (cTFH) cells have supported memory B cell activation and broadly neutralizing antibodies in HIV controllers. We investigated the contribution of LN SIV-specific TFH and cTFH cells to Env-specific humoral immunity in female rhesus macaques following a mucosal Ad5hr-SIV recombinant priming and SIV gp120 intramuscular boosting vaccine regimen and following SIV vaginal challenge. TFH and B cells were characterized by flow cytometry. B cell help was evaluated in TFH-B cell co-cultures and by real-time PCR. Vaccination induced Env-specific TFH and Env-specific memory (ESM) B cells in LNs. LN Env-specific TFH cells post-priming and GC ESM B cells post-boosting correlated with rectal Env-specific IgA titers, and GC B cells at the same timepoints correlated with vaginal Env-specific IgG titers. Vaccination expanded cTFH cell responses, including CD25+ Env-specific cTFH cells that correlated negatively with vaginal Env-specific IgG titers but positively with rectal Env-specific IgA titers. Although cTFH cells post-2nd boost positively correlated with viral-loads following SIV challenge, cTFH cells of SIV-infected and protected macaques supported maturation of circulating B cells into plasma cells and IgA release in co-culture. Additionally, cTFH cells of naïve macaques promoted upregulation of genes associated with B cell proliferation, BCR engagement, plasma cell maturation, and antibody production, highlighting the role of cTFH cells in blood B cell maturation. Vaccine-induced LN TFH and GC B cells supported anti-viral mucosal immunity while cTFH cells provided B cell help in the periphery during immunization and after SIV challenge. Induction of TFH responses in blood and secondary lymphoid organs is likely desirable for protective efficacy of HIV vaccines.
Assuntos
Imunidade Humoral , Imunidade nas Mucosas , Imunogenicidade da Vacina , Glicoproteínas de Membrana/administração & dosagem , Vacinas contra a SAIDS/administração & dosagem , Vírus da Imunodeficiência Símia/imunologia , Células T Auxiliares Foliculares/imunologia , Vacinação , Proteínas do Envelope Viral/administração & dosagem , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Células Cultivadas , Técnicas de Cocultura , Feminino , Memória Imunológica , Macaca mulatta , Glicoproteínas de Membrana/imunologia , Reto , Vacinas contra a SAIDS/imunologia , Células T Auxiliares Foliculares/metabolismo , Células T Auxiliares Foliculares/virologia , Vagina , Proteínas do Envelope Viral/imunologiaRESUMO
Vaccine strategies targeting the mucosal portal of entry may prevent HIV acquisition and systemic infection. Macrophages in cervicovaginal compartments are one of the first cell types to encounter virus upon vaginal exposure. Their activation can lead to recruitment of additional macrophages and CD4+ T-cells susceptible to viral infection. However, they are also critical in providing early protection against invading pathogens. Therefore, understanding their response to immunization is important for vaccine design. We immunized rhesus macaques twice mucosally with replicating adenovirus (Ad) SIV recombinants, followed by two intramuscular boosts with SIV gp120 protein. Macaques were subsequently challenged intravaginally with repeated low doses of SIVmac251. Using flow cytometry, we evaluated responses of cervicovaginal macrophages (CVM) and alveolar macrophages (AM) in bronchoalveolar lavage as initial immunization was to the upper respiratory tract. The frequency of CVM increased over the course of immunization; however, CCR5 expression significantly decreased. Significantly increased expression of the chemokines CCL3 (p < 0.01), CCL4, CCL5, and CXCL8 (p < 0.0001 for all) on CVM was seen post-1st Ad but their expression significantly decreased post-2nd boost. CD4+ T-cell frequency in the cervical mucosa remained unchanged. CVM FcγRIII expression was significantly increased at all time points post-immunization compared to naïve animals. FcγRIII expression post-2nd Ad positively correlated with the number of challenges needed for infection (r = 0.68; p = 0.0051). Vaccination increased AM FcγRIII expression which post-2nd boost correlated with antibody-dependent phagocytosis. Activation of AMs was evident by increased expression of CD40 and CD80 post-2nd Ad compared to naïve macaques. APRIL expression also significantly increased post-2nd Ad and correlated with B cell frequency in bronchoalveolar lavage (BAL) (r = 0.73; p = 0.0019) and total IgG in BAL-fluid (r = 0.53; p = 0.047). B cells cultured with SIV gp120-stimulated AM supernatant from vaccinated macaques exhibited significant increases in B cell activation markers CD38 and CD69 compared to B cells cultured alone or with AM supernatant from unvaccinated macaques. Overall, the vaccine regimen did not induce recruitment of susceptible cells to the vaginal mucosa but increased CVM FcγRIII expression which correlated with delayed SIV acquisition. Further, immunization induced expression of AM cytokines, including those associated with providing B cell help.