Maria del Pilar Martin
Emory University
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Featured researches published by Maria del Pilar Martin.
Nature Medicine | 2010
Sean P. Sullivan; Dimitrios G. Koutsonanos; Maria del Pilar Martin; Jeong Woo Lee; Vladimir Zarnitsyn; Seong-O Choi; Niren Murthy; Richard W. Compans; Ioanna Skountzou; Mark R. Prausnitz
Influenza prophylaxis would benefit from a vaccination method enabling simplified logistics and improved immunogenicity without the dangers posed by hypodermic needles. Here we introduce dissolving microneedle patches for influenza vaccination using a simple patch-based system that targets delivery to skins antigen-presenting cells. Microneedles were fabricated using a biocompatible polymer encapsulating inactivated influenza virus vaccine for insertion and dissolution in the skin within minutes. Microneedle vaccination generated robust antibody and cellular immune responses in mice that provided complete protection against lethal challenge. Compared to conventional intramuscular injection, microneedle vaccination resulted in more efficient lung virus clearance and enhanced cellular recall responses after challenge. These results suggest that dissolving microneedle patches can provide a new technology for simpler and safer vaccination with improved immunogenicity that could facilitate increased vaccination coverage.
PLOS ONE | 2009
Dimitrios G. Koutsonanos; Maria del Pilar Martin; Vladimir Zarnitsyn; Sean P. Sullivan; Richard W. Compans; Mark R. Prausnitz; Ioanna Skountzou
Background Influenza is a contagious disease caused by a pathogenic virus, with outbreaks all over the world and thousands of hospitalizations and deaths every year. Due to virus antigenic drift and short-lived immune responses, annual vaccination is required. However, vaccine coverage is incomplete, and improvement in immunization is needed. The objective of this study is to investigate a novel method for transdermal delivery using metal microneedle arrays (MN) coated with inactivated influenza virus to determine whether this route is a simpler and safer approach than the conventional immunization, capable to induce robust immune responses and confer protection against lethal virus challenge. Methodology/Principal Findings Inactivated A/Aichi/2/68 (H3N2) influenza virus was coated on metal microneedle arrays and applied to mice as a vaccine in the caudal dorsal skin area. Substantial antibody titers with hemagglutination inhibition activity were detected in sera collected two and four weeks after a single vaccine dose. Challenge studies in mice with 5×LD50 of mouse adapted Aichi virus demonstrated complete protection. Microneedle vaccination induced a broad spectrum of immune responses including CD4+ and CD8+ responses in the spleen and draining lymph node, a high frequency of antigen-secreting cells in the lung and induction of virus-specific memory B-cells. In addition, the use of MN showed a dose-sparing effect and a strong Th2 bias when compared to an intramuscular (IM) reference immunization. Conclusions/Significance The present results show that delivery of inactivated influenza virus through the skin using metal microneedle arrays induced strong humoral and cellular immune responses capable of conferring protection against virus challenge as efficiently as intramuscular immunization, which is the standard vaccination route. In view of the convenience of delivery and the potential for self-administration, vaccine-coated metal microneedles may provide a novel and highly effective immunization method.
Journal of Immunology | 2010
Ioanna Skountzou; Dimitrios G. Koutsonanos; Jin Hyang Kim; Ryan Powers; Lakshmipriyadarshini Satyabhama; Feda Masseoud; William C. Weldon; Maria del Pilar Martin; Robert S. Mittler; Richard W. Compans; Joshy Jacob
The 2009 H1N1 influenza virus outbreak is the first pandemic of the twenty-first century. Epidemiological data reveal that of all the people afflicted with H1N1 virus, <5% are over 51 y of age. Interestingly, in the uninfected population, 33% of those >60 y old have pre-existing neutralizing Abs against the 2009 H1N1 virus. This finding suggests that influenza strains that circulated 50–60 y ago might provide cross-protection against the swine-origin 2009 H1N1 influenza virus. To test this, we determined the ability of representative H1N1 influenza viruses that circulated in the human population from 1930 to 2000, to induce cross-reactivity to and cross-protection against the pandemic swine-origin H1N1 virus, A/California/04/09. We show that exposure of mice to the 1947 virus, A/FM/1/47, or the 1934 virus, A/PR/8/34, induced robust cross-protective immune responses and these mice were protected against a lethal challenge with mouse-adapted A/California/04/09 H1N1 virus. Conversely, we observed that mice exposed to the 2009 H1N1 virus were protected against a lethal challenge with mouse-adapted 1947 or 1934 H1N1 viruses. In addition, exposure to the 2009 H1N1 virus induced broad cross-reactivity against H1N1 as well as H3N2 influenza viruses. Finally, we show that vaccination with the older H1N1 viruses, particularly A/FM/1/47, confers protective immunity against the 2009 pandemic H1N1 virus. Taken together, our data provide an explanation for the decreased susceptibility of the elderly to the 2009 H1N1 outbreak and demonstrate that vaccination with the pre-1950 influenza strains can cross-protect against the pandemic swine-origin 2009 H1N1 influenza virus.
PLOS ONE | 2010
William C. Weldon; Bao-Zhong Wang; Maria del Pilar Martin; Dimitrios G. Koutsonanos; Ioanna Skountzou; Richard W. Compans
Background The recent swine-origin H1N1 pandemic illustrates the need to develop improved procedures for rapid production of influenza vaccines. One alternative to the current egg-based manufacture of influenza vaccine is to produce a hemagglutinin (HA) subunit vaccine using a recombinant expression system with the potential for high protein yields, ease of cloning new antigenic variants, and an established safety record in humans. Methodology/Principal Findings We generated a soluble HA (sHA), derived from the H3N2 virus A/Aichi/2/68, modified at the C-terminus with a GCN4pII trimerization repeat to stabilize the native trimeric structure of HA. When expressed in the baculovirus system, the modified sHA formed native trimers. In contrast, the unmodified sHA was found to present epitopes recognized by a low-pH conformation specific monoclonal antibody. We found that mice primed and boosted with 3 µg of trimeric sHA in the absence of adjuvants had significantly higher IgG and HAI titers than mice that received the unmodified sHA. This correlated with an increased survival and reduced body weight loss following lethal challenge with mouse-adapted A/Aichi/2/68 virus. In addition, mice receiving a single vaccination of the trimeric sHA in the absence of adjuvants had improved survival and body weight loss compared to mice vaccinated with the unmodified sHA. Conclusions/Significance Our data indicate that the recombinant trimeric sHA presents native trimeric epitopes while the unmodified sHA presents epitopes not exposed in the native HA molecule. The epitopes presented in the unmodified sHA constitute a “silent face” which may skew the antibody response to epitopes not accessible in live virus at neutral pH. The results demonstrate that the trimeric sHA is a more effective influenza vaccine candidate and emphasize the importance of structure-based antigen design in improving recombinant HA vaccines.
Vaccine | 2010
Ioanna Skountzou; Maria del Pilar Martin; Bao-Zhong Wang; Ling Ye; Dimitrios G. Koutsonanos; Will Weldon; Joshy Jacob; Richard W. Compans
Bacterial flagellins are potent inducers of innate immune responses in the mouse lung because they bind to TLR5 expressed on the apical surfaces of airway epithelial cells. TLR engagement leads to the initiation of a signaling cascade that results in a pro-inflammatory response with subsequent up-regulation of several cytokines and leads to adaptive immune responses. We examined the ability of two soluble flagellins, a monomeric flagellin expressed in Escherichia coli and a highly purified polymeric flagellin directly isolated from Salmonella, to enhance the efficacy of influenza vaccines in mice. Here we demonstrate that both flagellins co-administered intranasally with inactivated A/PR/8/34 (PR8) virus induced robust increases of systemic influenza-specific IgA and IgG titers and resulted in a more comprehensive humoral response as indicated by the increase of IgG2a and IgG2b subclass responses. Groups immunized with the adjuvanted vaccines were fully protected against high dose lethal challenge by homologous virus whereas inactivated PR8 alone conferred only partial protection. Finally we show that shortly after immunization the adjuvanted vaccines induced a dramatic increase in pro-inflammatory cytokines in the lung, resulting in extensive lung infiltration by granulocytes and monocytes/macrophages. Our results reveal a promising perspective for the use of both soluble monomeric and polymeric flagellin as mucosal vaccine adjuvants to improve protection against influenza epidemics as well as a range of other infectious diseases.
Mbio | 2012
Maria del Pilar Martin; William C. Weldon; Vladimir Zarnitsyn; Dimitrios G. Koutsonanos; Hamed Akbari; Ioanna Skountzou; Joshy Jacob; Mark R. Prausnitz; Richard W. Compans
ABSTRACT Microneedle patches (MN) provide a novel method of vaccine delivery to the skin with the objective of targeting the large network of resident antigen-presenting cells to induce an efficient immune response. Our previous reports demonstrated that cutaneous delivery of inactivated influenza virus-coated MN to mice protects against lethal infection. Protection is correlated with sustained levels of anti-influenza virus serum antibodies, hemagglutination inhibition titers, and robust cellular responses that are often stronger than those generated by intramuscular vaccination. Here we dissect the early events occurring in murine skin after microneedle delivery of inactivated influenza virus. We demonstrate correlation of immunization against influenza virus with a local increase of cytokines important for recruitment of neutrophils, monocytes and dendritic cells at the site of immunization. We also observed prolonged antigen deposition, and migration of matured dendritic cells bearing influenza virus antigen from the skin. IMPORTANCE The immunological mechanisms by which MN vaccination confers protective immunity are not well understood. The present study provides a first analysis of the early immune events after microneedle-based vaccination. The immunological mechanisms by which MN vaccination confers protective immunity are not well understood. The present study provides a first analysis of the early immune events after microneedle-based vaccination.
Clinical and Vaccine Immunology | 2011
William C. Weldon; Maria del Pilar Martin; Vladimir Zarnitsyn; Bao-Zhong Wang; Dimitrios G. Koutsonanos; Ioanna Skountzou; Mark R. Prausnitz; Richard W. Compans
ABSTRACT The emergence of the swine-origin 2009 influenza pandemic illustrates the need for improved vaccine production and delivery strategies. Skin-based immunization represents an attractive alternative to traditional hypodermic needle vaccination routes. Microneedles (MNs) can deliver vaccine to the epidermis and dermis, which are rich in antigen-presenting cells (APC) such as Langerhans cells and dermal dendritic cells. Previous studies using coated or dissolvable microneedles emphasized the use of inactivated influenza virus or virus-like particles as skin-based vaccines. However, most currently available influenza vaccines consist of solubilized viral protein antigens. Here we test the hypothesis that a recombinant subunit influenza vaccine can be delivered to the skin by coated microneedles and can induce protective immunity. We found that mice vaccinated via MN delivery with a stabilized recombinant trimeric soluble hemagglutinin (sHA) derived from A/Aichi/2/68 (H3) virus had significantly higher immune responses than did mice vaccinated with unmodified sHA. These mice were fully protected against a lethal challenge with influenza virus. Analysis of postchallenge lung titers showed that MN-immunized mice had completely cleared the virus from their lungs, in contrast to mice given the same vaccine by a standard subcutaneous route. In addition, we observed a higher ratio of antigen-specific Th1 cells in trimeric sHA-vaccinated mice and a greater mucosal antibody response. Our data therefore demonstrate the improved efficacy of a skin-based recombinant subunit influenza vaccine and emphasize the advantage of this route of vaccination for a protein subunit vaccine.
The Journal of Infectious Diseases | 2011
Dimitrios G. Koutsonanos; Maria del Pilar Martin; Vladimir Zarnitsyn; Joshy Jacob; Mark R. Prausnitz; Richard W. Compans; Ioanna Skountzou
BACKGROUND A major goal in influenza vaccine development is induction of serological memory and cellular responses to confer long-term protection and limit virus spread after infection. Here, we investigate induction of long-lived immunity against the 2009 H1N1 virus after skin vaccination. METHODS BALB/c mice received a single dose of 5 μg inactivated A/California/04/09 virus via coated metal microneedles (MN) applied to skin or via subcutaneous injection. RESULTS MN or subcutaneous vaccination elicited similar serum IgG and hemagglutination inhibition titers and 100% protection against lethal viral challenge 6 weeks after vaccination. Six months after vaccination, the subcutaneous group exhibited a 60% decrease in functional antibody titers and extensive lung inflammation after challenge with 10 × LD(50) of homologous virus. In contrast, the MN group maintained high functional antibody titers and IFN-γ levels, inhibition of viral replication, and no signs of lung inflammation after challenge. MN vaccination conferred complete protection against lethal challenge, whereas subcutaneous vaccination induced only partial protection. These findings were further supported by high numbers of bone marrow plasma cells and spleen antibody-secreting cells detected in the MN group. CONCLUSIONS A single skin vaccination with MN induced potent long-lived immunity and improved protection against the 2009 H1N1 influenza virus, compared with subcutaneous injection.
Hepatology | 2015
Stefan M. Brunner; Christoph Rubner; Rebecca Kesselring; Maria del Pilar Martin; Eva Griesshammer; Petra Ruemmele; Thomas Stempfl; Andreas Teufel; Hans J. Schlitt; Stefan Fichtner-Feigl
Interleukin‐33 (IL‐33), a cytokine with pleiotropic functions, is elevated in serum of patients with hepatocellular carcinoma (HCC). This study investigated the effects of local IL‐33 expression in resected HCC on patient survival and on the immunological and molecular tumor microenvironment. Tissue of resected HCCs was stained for hematoxylin and eosin, Masson trichrome, alpha‐smooth muscle actin, IL‐33, CD8, and IL‐13 and analyzed by flow cytometry. Besides histomorphologic evaluation, the immunohistochemical stainings were analyzed for the respective cell numbers separately for tumor area, infiltrative margin, and distant liver stroma. These findings were correlated with clinical data and patient outcome. Further, gene expression of different HCC risk groups was compared using microarrays. In multivariable analysis, infiltration of HCCs by IL‐33+ cells (P = 0.032) and CD8+ cells (P = 0.014) independently was associated with prolonged patient survival. Flow cytometry demonstrated that cytotoxically active subpopulations of CD8+ cells, in particular CD8+CD62L–KLRG1+CD107a+ effector‐memory cells, are the main producers of IL‐33 in these HCC patients. Using infiltration by IL‐33+ and CD8+ cells as two separate factors, an HCC immune score was designed and evaluated that stratified patient survival (P = 0.0004). This HCC immune score identified high‐ and low‐risk patients who differ in gene expression profiles (P < 0.001). Conclusion: Infiltration of HCCs by IL‐33+ and CD8+ cells is independently associated with prolonged patient survival. We suggest that this is due to an induction of highly effective, cytotoxically active CD8+CD62L–KLRG1+CD107a+ effector‐memory cells producing IL‐33. Based on these two independent factors, we established an HCC immune score that provides risk stratification for HCC patients and can be used in the clinical setting. (Hepatology 2015;61:1957‐1967)
PLOS ONE | 2010
Maria del Pilar Martin; Shaguna Seth; Dimitrios G. Koutsonanos; Joshy Jacob; Richard W. Compans; Ioanna Skountzou
Background The respiratory illnesses caused by influenza virus can be dramatically reduced by vaccination. The current trivalent inactivated influenza vaccine is effective in eliciting systemic virus-specific antibodies sufficient to control viral replication. However, influenza protection generated after parenteral immunization could be improved by the induction of mucosal immune responses. Methodology/Principal Findings Transcutaneous immunization, a non-invasive vaccine delivery method, was used to investigate the quality, duration and effectiveness of the immune responses induced in the presence of inactivated influenza virus co-administered with retinoic acid or oleic acid. We observed an increased migration of dendritic cells to the draining lymph nodes after dermal vaccination. Here we demonstrate that this route of vaccine delivery in combination with certain immunomodulators can induce potent immune responses that result in long-term protective immunity. Additionally, mice vaccinated with inactivated virus in combination with retinoic acid show an enhanced sIgA antibody response, increased number of antibody secreting cells in the mucosal tissues, and protection from a higher influenza lethal dose. Conclusions/Significance The present study demonstrates that transdermal administration of inactivated virus in combination with immunomodulators stimulates dendritic cell migration, results in long-lived systemic and mucosal responses that confer effective protective immunity.