O presente estudo teve como principal objetivo aprimorar os efeitos antitumorais de uma nova estratégia imunoterapêutica para controle de tumores induzidos pelo vírus do papiloma humano tipo 16 (HPV-16). Para tal finalidade foi utilizado um novo conceito de imunoterapia ativa, baseada em uma vacina de DNA recombinante, desenvolvida no Laboratório de Desenvolvimento de Vacinas da USP (pgDE7h) e diferentes abordagens experimentais delineadas com a finalidade de aumentar a eficácia terapêutica do tratamento. Desta forma, o presente trabalho focou no desenvolvimento de novos sistemas de entrega para a vacina de DNA empregando três nanocarregadores distintos, de natureza lipídica, proteica ou peptídica, e a avaliação da eficácia terapêutica desses frente a tumores pré-estabelecidos. O presente trabalho também avaliou a combinação da imunoterapia, baseada no vetor pgDE7h, com a quimioterapia, empregando o composto cisplatina, de forma a permitir o tratamento de tumores em estágios mais avançados de crescimento. Os resultados demonstram que a associação do plasmídeo vacinal com vesículas peptídicas mostrou-se capaz de ativar células dendríticas murinas in vitro e promover aumento na sobrevivência de animais frente ao modelo de tumores subcutâneos, sem induzir toxicidade. Quando combinada ao tratamento com cisplatina, a vacina, principalmente associada à eletroporação, demonstrou um efeito sinérgico, promovendo regressão total de tumores, aumento expressivo na ativação de linfócitos T CD8 E7-específicos, indução de resposta de memória efetora e memória residente e controle de populações imunossupressoras de forma sistêmica e no microambiente tumoral. Em resumo, a pesquisa ampliou os conhecimentos sobre a ação da imunoterapia ativa contra tumores induzidos por HPV e abriu perspectivas importantes para sua utilização em condições clínicas. / The present study aimed to improve the antitumor effects of a new immunotherapeutic strategy for the control of tumors induced by human papillomavirus type 16 (HPV-16). For this purpose, a new concept of active immunotherapy based on a recombinant DNA vaccine developed at the Laboratory of Vaccine Development at USP (pgDE7h) was used, and different experimental approaches were designed to increase the therapeutic efficacy of the treatment. Thus, the present work focused on the development of new delivery systems for the DNA vaccine using three distinct nanocarregadores, of a lipid, protein or peptidic nature, and the evaluation of the therapeutic efficacy of these in front of pre-established tumors. The present study also evaluated the combination of pgDE7h-based immunotherapy with chemotherapy using the cisplatin compound to allow the treatment of tumors in more advanced stages of growth. The results demonstrate that the association of the peptide-vesicle vaccine plasmid was shown to activate murine dendritic cells in vitro and promote increased survival of animals against the subcutaneous tumor model without inducing toxicity. When combined with cisplatin treatment, the vaccine, mainly associated with electroporation, demonstrated a synergistic effect, promoting total tumor regression, expressive increase in the activation of CD8 E7-specific T lymphocytes, induction of effector and resident memory response and control of immunosuppressive populations in a systemic way and in the tumor microenvironment. In summary, the research expanded knowledge about the action of active immunotherapy against HPV-induced tumors and opened important perspectives for its use under clinical conditions.

O Streptococcus pneumoniae, também conhecido como pneumococo, é um importante agente etiológico causador de pneumonia, bacteremia, meningite e otite aguda do ouvido médio, acometendo especialmente crianças e idosos. A cápsula polissacarídica (PS) é o fator de virulência mais importante e localiza-se na superfície do microrganismo e tem ação anti-fagocítica in vivo. O pneumococo expressa pelo menos 91 cápsulas diferentes, que são química e sorologicamente distintas. Usualmente, a cápsula é o antígeno das vacinas anti-pneumocócicas, tanto como polissacarídeo livre ou conjugado a proteínas. O sorotipo 6B acomete principalmente crianças e é o segundo mais prevalente no Brasil, e a otimização das condições de cultivo buscando maior produtividade em PS é o alvo desta tese. Simultaneamente, também foi investigada a influência do inóculo e da glicose residual no instante do pulso ou do início da alimentação em cultivos descontínuos alimentados. Nos cultivos descontínuos alimentados foi observado que quanto menor a densidade óptica da cultura do inóculo, maior a concentração de PS obtida. A concentração da glicose residual no momento do pulso provavelmente influenciou a produção de PS: a produção foi maior quando o pulso foi dado ainda em altas concentrações de substrato. Por isso, obteve-se uma produção de PS ~390 mg/L em cultivo descontínuo alimentado com pulso, quando DO 600 nm da cultura do inóculo ~1,6 e o pulso de glicose e acetato de amônio ~15 g/L. Observou-se também que, mesmo com DO do inóculo ~1,65, a produção de PS foi somente 248 mg/L, devido à aplicação do pulso quando a concentração de glicose residual era ~4,5 g/L. A menor produção de PS foi obtida quando a DO da cultura do inóculo foi ~2,6 e a concentração de glicose residual ~3,4 g/L, gerando somente 194 mg/L de PS. Assim, cultivos descontínuos alimentados com pulso renderam melhores resultados que os cultivos descontínuos alimentados. A alimentação constante rendeu maior quantidade de PS quando comparada à alimentação exponencial. E tanto os ensaios descontínuos com ou sem pulso e os descontínuos alimentados foram melhores do que os cultivos contínuos, principalmente se considerarmos a facilidade de operação. O efeito da concentração residual da glicose no instante da alimentação na produção de PS é provavelmente influenciado pela presença de outros componentes do meio, devido aos requerimentos nutricionais do pneumococo. O estado fisiológico do inóculo determinou uma importante correlação entre a produção de PS nos cultivos descontínuos alimentados do sorotipo 6B: cultura do inóculo no meio da fase exponencial rendeu maior produção de PS. Esta correlação poderia ser conseqüência do perfil de crescimento do microrganismo in vitro e da ação de enzimas líticas após a fase exponencial. Foi observado, portanto, um efeito sinérgico entre a DO da cultura do inóculo, a concentração de glicose residual no momento de alimentação e produção de PS nos cultivos descontínuos alimentados. / Streptococcus pneumoniae is a major pathogen commonly responsible for pneumonia, bacteraemia, meningitis and otitis media, especially among young children and older adults. The most prominent pneumococcal virulence factor is the capsular polysaccharide (PS), which coats the surface of the bacterium and acts as an antiphagocytic factor in vivo. S. pneumoniae express at least 91 distinct capsules which are chemically and serologically distinct. The capsule is currently used as antigen in pneumococcal vaccines, either as free polysaccharide or conjugated to proteins. Pneumococcal serotype 6B is the second most prevalent in Brazil and the optimization of cultivation conditions is part of this study. Simultaneously we investigated the influence of the growth phase of the inoculum and the residual glucose concentration at the instant of the pulse or the start of feeding on PS production in batch and fed-batch cultivation. Streptococcus pneumoniae serotype 6B strain ST 433/03 was used. Bench scale experiments were carried out using a variant of the Hoeprich medium, containing glucose, acid-hydrolyzed casein, dialyzed yeast extract, L-glutamine and asparagine as nitrogen sources, choline as a growth factor and salts. The experiments were conducted in bioreactors monitored by the LabView 7.1program. It was observed in fed-batch cultivation, that the lower was the OD of the starter culture, the higher was the PS concentration obtained. The residual glucose concentration at the moment of the pulse also influenced the PS production: the PS production was higher when the pulse was given at higher residual glucose concentration. Hence, in fed-batch culture the highest PS production (387 mg/L) was obtained using an OD=1.6 of the starter culture and giving the pulse when the residual glucose was ~15 g/L. Using a similar inoculum (OD=1.65), the PS concentration reached 248 mg/L after giving the pulse when the residual glucose was 4.5 g/L. The lowest PS production was obtained when a culture with an OD=2.6 was inoculated into the reactor and the pulse was given when the residual glucose was 3.4 g/L (PS=194 mg/L). The effect of the residual glucose concentration at the instant of the start of feeding on PS production was probably influenced by the presence of other components in the concentrated feeding medium, which could better fit the nutritional requirements of the microorganism. The physiological state of the inoculum showed an important correlation to the PS production in batch and fed-batch cultivation of S. pneumoniae serotype 6B: mid-log phase inocula yielded high PS production. This correlation is consequence of the in vitro growth profile, the action of lytic enzymes after the log phase. In fed-batch cultivation, it was also observed a synergic effect of the inoculum OD and the residual glucose concentration in the moment of the pulse on PS production.

No Brasil, e em outros paises de clima tropical, os carrapatos se tornaram um enorme problema economico de^$de que a industria do gado se desenvolveu. O carrapato Boophilus microplus, um dos artropodes mais importantes na veterinaria, causa efeitos direto, como suc,cao de sangue, e indireto, como a transmissao de uma grande variedade de patogenos que normalmente resulta em infec,c~es letais. As vacinas genicas contendo o antigeno Bm86, uma proteina ligada a membrana do intestino do carrapato B. microplus, representam uma alternativa atrativa aos acaricidas para controlar as infesta~oes por carrapatos em contrapartida aos inconvenientes produtos quimicos. Devido sua administra,cao ser feita em 4 doses no primeiro ano, seguida de refor,cos a cada seis meses, estas formula,coes vacinais nao s3c adequadas para paises com cria,cao extensiva de gado, como no Brasil. Visando uma libera~ao sustentada do antigeno Bm86, neste trabalho desenvolveuse uma vacina de dose unica baseada em microesferas polimericas. Para obter o padrao de liberac,ao desejavel, diferentes formula,coes e parametros de processo foram variados, como a composi,cao do polimero, a taxa entre os monomeros ^Uacido latico:acido glicolico\" e o tamanho das microparticulas. As formula,coes foram preparadas pelo metodo de emulsao multipla e evapora,cao do solvente. A formula~ao que melhor se enquadrou nos objetivos da vacina de dose unica foi preparada com PLGA 75:25, solu,cao 3% de PVA como estabilizante, agita,cao de 11000 rpm para forma,cao da emulsao primaria e de 800 rpm para forma,cao da emulsao multipla e evapora,cao do solvente. As particulas assim obtidas apresentaram um tamanho medio de 25 ,um, uma taxa de encapsula,cao maior que 90% e aproximadamente 50% da proteina foi liberada in vitro em 60 dias. Analises por SDS-PAGE e Westem Bloning revelaram que a proteina se manteve integra apos encapsula,cao. Os resultados da avalia,cao da imunogenicidade em bovinos mostraram que a formula,cao baseada em microesferas polimericas biodegradaveis e habil a conseguir, com uma unica dose, uma resposta imune similar aquela conseguida com tres doses das formula,coes convencionais da vacina de Bm86. / In Brazil, and in others tropical countries, the ticks have become a huge economic problem since the industry of livestock has developed. Ticks and tick-borne diseases affect animal and human health and are the cause of significant economic losses. The cattle tick Boophilus microplus is one of the most important arthropods in veterinary. This tick species causes both direct effects, such as blood sucking, and indirect effects, such as transmission of a wide variety of pathogens, which usually result in lethal infections. The gene vaccines based on Bm86 antigen, a midgut membrane-bound protein of the cattle tick B. microplus, represent a good alternative to control tick infestations, compared to chemicals. However, due to these vaccine formulations need 4 doses over the first year with booster at each 6 months to be effective, they are not suitable for countries with extensive cattle raising, like Brazil. Aiming a sustained release of Bm86 antigen, in this work we developed a single shot vaccine based on Bm86 loaded polymeric microspheres. In order to obtain desired release patterns, different formulations and processing parameters were varied, for example, the composition of the polymer, the monomer ratio lactic acid:glycolic acid and the size of the microparticles. The formulations were prepared by solvent evaporation method based on double emulsion. The formulation that presented better result as single shot vaccine was prepared with PLGA 75:25, solution 3% of PVA as stabilizer, agitation of 11000 rpm to form the primary emulsion and 800 rpm to obtain the double emulsion and solvent evaporation. The particles thus obtained presented an average size of 25 m, encapsulation ratio greater than 90% and approximately 50% of the protein was released in vitro in 60 days. Analysis by SDSPAGE and Western Blot showed that the integrity of the protein remained after encapsulation. The immunogenic studies showed that the formulation based onbiodegradable polymeric microspheres is able to elicit, with a single dose, an immune response and protection similar to that attained with 3 doses of conventional Bm86 vaccine formulations.

Neisseria gonorrhoeae is a strict human pathogen and the causative agent of the sexually transmitted disease, gonorrhea. Gonococcal (GC) diseases remain one of the most reported sexually transmitted infections (STI) worldwide, representing a significant threat to reproductive health and burden on global health systems, accounting for 541,987 disability adjusted-life years in the year 2011. Infection by N. gonorrhoeae also increases the likelihood of patient acquisition and transmission of human immunodeficiency virus (HIV). Unfortunately, antibiotic treatment to gonococcal diseases is being threatened by the rapid spread of resistance to third-generation cephalosporins, the remaining treatment option used in clinics. The urgency of the situation is compounded by the relative lack of immunological protection conferred by previous infection by the bacterium. In response to the emergence of multidrug resistance, renewed energies are being directed towards the development of an effective, broadly protective vaccine. Difficulties in vaccine development arise from a lack of known correlates of protective immunity; there is no known broadly cross-protective immunity to GC and a truly reflective animal model has not been available. Nonetheless, previous studies have indicated that porins, neisserial major outer membrane proteins, are promising vaccine candidates. PorB makes up over 60% of the bacterium's outer membrane content and is involved in solute and ion exchange, invasion of target host cells, and evasion of host immunity. Porins from both the gonococcus and the meningococcus have been shown to have immunostimulatory activity, boosting B and dendritic (DC) cell proliferation and maturation in the absence of an exogenous adjuvant as mediated by TLR2 and MyD88. Importantly, as a potential vaccine candidate, PorB has relatively low antigenic variability, and can induce bactericidal antibodies. Gonococcal PorB was purified from a genetically modified strain, MS11delP3, which lacks another outer membrane protein, RMP, which is known to induce bactericidal blocking antibodies. PorB was formed into pure protein micelles, termed proteosomes, to protect the integrity of the native trimeric structure. Our study demonstrated that gonococcal PorB is able to stimulate both human embryonic kidney (HEK) cell line that overexpresses TLR2 and mouse primary macrophages (similar to the meningococcal PorB). To test PorB's immunogenicity, mice were immunized three times at two week intervals with PorB and porin specific IgG levels were measured. Unfortunately, PorB elicited lower levels of porin specific IgG than what was expected, which may be due to technical issues. We are currently investigating various possibilities. In addition, further immunization studies shall be carried out to better contextualize these results.

Influenza A virus (IAV) infection is a serious respiratory disease associated with significant morbidity and mortality worldwide. Annual vaccination is the most effective way to prevent infection and its potentially severe complications; however, the vaccines currently offered have several drawbacks that limit its availability and protective efficacy. Influenza virus-like particles (VLPs), which lack viral genetic material and are non-infectious, represent a promising vaccine candidate. Previous reports have shown VLPs are more immunogenic than subunit or recombinant proteins, and confer protection upon lethal challenge. A critical component of this protection is mediated by influenza HA-specific neutralizing Abs produced by memory B cells and plasma cells, the cellular products of the germinal center (GC) reaction. While preliminary studies have examined the humoral immune response to VLP vaccination, the current study is the first to characterize the GC response in secondary and tertiary lymphoid tissues. Mice were vaccinated with influenza VLPs using three immunization routes: subcutaneous (s.c.), intramuscular (i.m.), and intranasal (i.n.) and the GC response was assessed over time. Robust GC reactions were induced in the dLNs regardless of vaccination route, though the largest response was generated with VLPs s.c. The pattern of isotype expression was remarkably similar between routes, with IgM+ and IgG2+ B cells representing the majority of the GC B cell population. Mucosal immune responses in the upper (nasal) and lower (lung) airway were measured in mice vaccinated i.n. Marked GC reactions were induced in the nasal-associated lymphoid tissue (NALT), while the pulmonary response was relatively modest and short-lived compared to infection with IAV. Within the GC B cell population, IgM+ and IgG2+ B cells made up the majority, similar to the dLN response. Importantly, the pattern of isotype expression induced by VLPs mimicked the response induced by natural IAV infection, and suggests that VLPs contain the necessary innate immune agonists to induce a TH1 biased response.

Due to the growing burden of malignancy and chronic infections, manipulating CD8+ T cell responses for clinical use has become an important goal for immunologists. CD8+ T cells have the unique capacity to recognize and kill tumor cells and intracellular pathogens. Thus far, failed or only minimally effective T cell vaccines against chronic pathogen infections and tumors have highlighted basic knowledge gaps for eliciting memory CD8+ T cell protection. Defining the immunological mechanisms that determine protective capacity and longevity in T cells will be critical to both therapeutic and prohylactic vaccine efficacy. My studies focus on strategies to manipulate effector and memory CD8+ T cell responses, including their mechanisms of action. Specifically, I show that dendritic cell (DC) immunization coupled with relatively early (days 1-3) or late (days 4-6) administration of enhanced IL-2 signals drive either effector or memory programs. DC + IL-2c administered 4-6 days post-DC transfer is shown to enhance Ag-specific effector CD8+ T cell responses; this approach is further explored in the context of a cancer immunotherapy, demonstrating effective control of tumor burden in multiple murine models of cancer. Temporal alterations of IL-2 signaling from day 4-6 to day 1-3 post-DC immunization is shown to increase memory potential and memory CD8+ T cell numbers long-term. Additional studies reveal CTLA-4-mediated down-regulation of B7-ligands on DCs after IL-2c treatment, demonstrating that weaker or more transient signaling through the CD28-B7 axis may favor memory CD8+ T cell programs. My work contributes valuable concepts in memory CD8 T cell generation to develop T cell vaccines that are both safe and predictable.

Staphylococcus aureus causes significant illnesses throughout the world, including toxic shock syndrome (TSS), pneumonia, and infective endocarditis. Major contributors to S. aureus illnesses are secreted virulence factors it produces, including superantigens and cytolysins. Rabbit cardiac physiology is considered similar to humans, and rabbits exhibit susceptibility to S. aureus superantigens and cytolysins. As such, rabbits are an excellent model for studying pneumonia, infective endocarditis, and sepsis, We examined the ability of USA200, USA300 and USA400 strains to cause vegetations and lethal sepsis in rabbits. USA200, TSST-1+ strains that produce only low amounts of Α-toxin, exhibited modest LD50 in sepsis (1x108-5x108) colony-forming units (CFUs), and 3/4 caused significant IE. USA200 strain MNPE, which produces high levels of Α-toxin, was both highly lethal (LD50 5x106 CFUs) and effective in causing IE. In contrast, USA300 strains were highly effective in causing lethal sepsis (LD50s 1 x 106 and 5 x 107 CFUs) but were minimally capable of causing IE. USA400 strains were both highly lethal (LD50s of 1 x 107 and 5 x 107 CFUs) and highly effective causes of IE. Additional studies investigated the role of phenol soluble modulins in infection. We showed that PSMs are important for the ability of S. aureus to cause sepsis but not infective endocarditis. Additionally, immunization against PSMs did not protect rabbits from lethal infection. Our studies show that clonal groups of S. aureus differ in abilities to cause infective endocarditis and lethal sepsis and suggest that secreted virulence factors, including superantigens and cytolysins, account for some of these differences. This thesis also investigates the use of superantigens and cytolysins as staphylococcal vaccine candidates. We generated three TSST-1 mutants; G31S/S32P, H135A, and Q136A. All rabbits administered these TSST-1 toxoids generated strong antibody responses (titers>10,000) that neutralized native TSST-1 in TSS models, both in vitro and in vivo. These TSST-1 mutants lacked detectable residual toxicity. Additionally, the TSST-1 mutants exhibited intrinsic adjuvant activity, increasing antibody responses to a second staphylococcal antigen (Β-toxin). This effect may be due to TSST-1 mutants binding to the immune co-stimulatory molecule CD40. The superantigens TSST-1 and SEC and the cytolysin Α-toxin are known to contribute to staphylococcal pneumonia. Immunization of rabbits against these secreted toxins provided complete protection from highly lethal challenge with a USA200 S. aureus strain producing all three exotoxins; USA200 strains are common causes of staphylococcal infections. The same three exotoxins plus the cytolysins Β-toxin and Γ-toxin contribute to infective endocarditis and sepsis caused by USA200 strains. Immunization against these five exotoxins protected rabbits from infective endocarditis and lethal sepsis. Additionally, a heptavalent vaccine composed of the pentavalent units plus SEB and SE-l X protected rabbits from lethal pneumonia caused by USA100 strain 209. Passive immunization using pooled sera protects previously non-immunized rabbits from lethal pneumonia due to MNPE. These data suggest that immunization against toxoid proteins of S. aureus exotoxins protects from serious illnesses, and concurrently superantigen toxoid mutants provide endogenous adjuvant activity.

Allergies are considered atopic diseases, or diseases that cause the immune system to create an abnormal amount of IgE antibodies when the body is exposed to an allergen. Allergies affect many people around the world, however many studies have shown a higher rate of allergy in developed countries when compared to developing countries. This discrepancy is hypothesized to be in part because of a decrease in parasitic infections, which have shown to have a protective effect for autoimmune-type diseases, like allergies. There are not many long-term, effective allergy treatments, however a promising allergen-specific immunotherapy technique uses a vaccine that targets B cell epitopes with the hope of increasing the amount of IgG antibodies as opposed to IgE specific antibodies to decrease the likelihood of an allergic reaction. This paper proposes a study that combines the protective effects of a parasite infection with a helminth infection and a B cell epitope vaccination, an already studied BM32 vaccine, to improve allergy symptoms of those with grass pollen allergy. This combination treatment will aim to decrease the number of symptomatic days, eosinophil count found at a scratch test site, and IgE antibodies found within the blood in grass pollen allergic people during peak grass pollen season.

Neonates are more susceptible to influenza virus infection than adults, resulting in increased morbidity and mortality as well as delayed clearance of the virus. Efforts to improve influenza infection outcomes in neonates typically center on prevention, although current vaccines fall short of complete protection and can only be administered in humans after 6 months of life. We propose that as the neonatal immune system responds differently than the adult immune system, interventions that are efficacious or tolerable in adults cannot be guaranteed to perform the same in neonates. T cell vaccines that target conserved influenza virus epitopes have been proposed for conferring protection to multiple influenza virus strains, but if T cell vaccines will be used in infants and adults, neonates must be able to respond to the same T cell antigens as adults. Mouse pups responded to influenza virus peptide PA224-233 but not NP366-374 during influenza virus infection in contrast to the codominant adult response. Mice infected as pups also generated diminished T cell memory compared to mice infected as adults and displayed skewed immunodominance during secondary infection. Adult bone marrow derived dendritic cells (BMDCs) improved viral clearance when loaded with influenza virus and promoted NP366-374-specific CD8+ T cell responses in infected pups. BMDC peptide vaccination could stimulate PA224-233-specific but not NP366-374-specific CD8+ T cell responses in pups, but, PA224-233 vaccination offered no protection to pups during lethal infection. These data suggest that altered immunodominance must be considered when stimulating CD8+ T cell responses in adults and neonates. Immaturity and active suppression of immune responses are both factors in neonatal vulnerability to disease. Specifically, active suppression of neonatal immunity by regulatory T cells (Tregs) has been proposed as a driving factor in diminished neonatal immunity, but removing these cells can compromise viral defense or increase deleterious inflammation. Mice that lacked Tregs displayed compromised anti-influenza antibody responses and decreased lymph node responses during influenza virus infection. A high proportion of pup Tregs also expressed Gata3. Transgenic pups with a Treg specific Gata3 knockout displayed an increase in Tbet expression in both conventional and regulatory T cells and an increase in IFNγ producing CD4+ T cells in the lungs during infection. These data suggest that Tregs are required for effective humoral responses to influenza virus and that Gata3 expression influences Treg suppressive function in neonates.

Caregivers' compliance with polio vaccine regimens and timely receipt of the recommended 4 doses of polio vaccine are pivotal to eliminating polio. This cross sectional study, conducted in Lagos State, Nigeria, examined polio vaccine compliance and demographic attributes of caregivers' for statistically significant associations. Using an adapted health belief model theoretical framework, 1,200 participants were recruited from well-baby clinics in 8 local government areas in Lagos State. Participants completed a brief demographic survey providing data on caregivers' age, gender, residence (rural or urban), and their level of education as well as records from their children's immunization cards. Data obtained were tested for associations between caregiver's demographic information and their children's receipt of polio doses within specified timelines using chi-square and logistic regression analysis. Fisher's exact analysis were conducted for variables with frequencies less than 5. The only significant association recorded was between the receipt of Polio Dose A and location of caregivers' residence: Rural dwelling caregivers were less likely to receive the first dose of polio. Results showed Polio Dose D to be the dose most likely received in an untimely manner as well as most likely missed of the 4 doses. Logistic regression analysis did not show any variable to be of greater odds in predicting completion of the 4 doses or compliance with timelines of their receipt. Study's results may inspire polio program planners to develop interventions that broaden the immunization coverage for rural dwellers to include nontraditional maternity locations. Positive social change will ensue by the improvement caregivers' compliance with full polio dose receipts with timelines, maximizing immunity.