As part of its routine anniversary activities, the Research Institute for Tropical Medicine (RITM) through its Research and Innovation Office (RIO) held its 42nd Research Forum on April 26, 2023 at the RITM Auditorium with the theme “PISTA: :Promoting Interoffice Collaboration & Showcasing Scientific Endeavors Through Annual conferences” which featured five (5) research studies of the Institute’s select researchers.
“Good researchers evaluate data carefully and search for patterns that will lead to [a] conclusion. This quality helps us find meaning in our observation[s] and data,” said officer-in-charge RITM Director IV Atty/Dr. Ana Liza Hombrado-Duran in her inspirational message.
“Research is always done in context. Collaboration is very important, but it is a responsibility of local investigators to put the research into context,” according to Parasitology Department Head Dr. Fe Esperanza Caridad Espino in her keynote message.
The research forum was under the supervision of RIO Head Dr. Charissa Fay Corazon Borja-Tabora and hosted by Committee for Learning and Development Supervising Science Research Specialist Mr. Ryan Castro.
Development of antibody detection kit for COVID-19 using enzyme immunoassay
The first study presented by Mr. Jhunel G. Vinarao of the Electron Microscopy Section, focused on COVID-19 test kits. In mitigating the transmission of the disease, early detection becomes crucial. With this, the need to capacitate relevant personnel in disease testing arises, in order to avoid reliance on overseas procurement of test kits was discussed. Thus, the feasibility of a COVID-19 antibody test kit using enzyme immunoassay was developed.
The methodology of the study involved a “non-experimental clinical trial” of confirmed COVID-19 positive and negative populations through electrochemiluminescent immunoassay (ECLIA). Serum samples involved were collected from Central Luzon (Region III), CALABARZON (Region IV-A), and the National Capital Region (NCR).
The study produced evidence that antibody detection kits may be generated using local capabilities and in the absence of reagents, conjugates, and antibodies from abroad. This was proven by a successful clinical validation of the test kits. The study also proved that the Enzyme Linked Immunosorbent Assay (ELISA) optimization framework may be implemented as a response to future public health concerns.
Lineage BA.2 dominated the Omicron SARS-CoV-2 epidemic wave in the Philippines
Despite the decrease in COVID-19 cases, the transmission of SARS-CoV-2, the causative agent of COVID-19 is still rampant. This phenomenon causes the development of new variants of the virus which may eventually lead to the production of mutant strains. In fact, the World Health Organization (WHO) in November 2021, designated the Omicron variant of SARS-CoV-2 as a variant concern (VOC). Prior to Omicron, the Alpha, Beta, Gamma, and Delta variants were also declared as VOCs. The existence of several SARS-CoV-2 variants becomes alarming as each one has unique mutations in the genome of the virus, with emphasis on the S gene. This can potentially increase the rate of virus transmission or severity of the disease as opposed to the isolated viruses in the early years of the COVID-19 pandemic.
With the aforementioned considered, there is a need to unearth the epidemiological patterns of the dominant variant of concern to inform the COVID-19 response of the country to possibly control further mutations of SARS-CoV-2.
The study presented by Molecular Biology Laboratory’s Francisco Gerardo Polotan, utilized the framework from the Genomic Epidemiology of COVID (GECO) in the Philippines Project in the collection of SARS-CoV-2 sequences. RNA samples that were confirmed SARS-CoV-2 positive through polymerase chain reaction (PCR) had undergone whole genome sequencing through the ARTIC network multiplex method.
Rather than the previous BA.1 Omicron subvariant, the study proposes that the BA.2 Omicron subvariant drove the Omicron wave in the country in 2021, as majority of the isolated sequences were of BA.2 lineage. With this, BA.1 and BA.2 Omicron subvariants in the country were hypothesized to be exhibiting epidemiological patterns different from each other. Instead of collection of genomic samples during the intermittent exploration of the current VOC, the researchers also assume that the genomic samples would have “minimal genetic differences” between isolated sequences if collected during “sustained transmission”.
Cellular Immunity and Resistance to Schistosomiasis in the Philippines (CRISTAL)
On a global scale, Schistosomiasis continues to pose a threat to roughly 12 million people. While in the country, the disease affects approximately 2 million Filipinos. Schistosomiasis is an infectious disease caused by the schistosome parasite that inhabits one’s blood vessels and eventually causes organ damage. Schistosome cercariae are shed by snail intermediate hosts living in freshwater. These fork-tailed structures penetrate the skin of the human host resulting to schistosomiasis. Schistosomiasis caused by Schistosoma japonicum is the most endemic in the Philippines.
The study presented by Mr. Mario Quimson IV of the Immunology Department aimed to gauge the “role of immune cells in resistance or susceptibility” to being reinfected by S. japonicum before and after praziquantel treatment. Stools of participants involved in the study were subjected to Kato Katz examination and were then tested for S. japonicum reinfection status one (1) year after praziquantel treatment.
The study revealed that praziquantel has caused significant reduction in mortality and severe end-organ morbidity. Praziquantel is deemed insufficient to address prevalent transmission of schistosomiasis. Reinfection can still occur in populations reliant on water sources that are contaminated. The study also reveals that IgG antibodies specific to a schistosome can inform future (re)infection. The researchers recommend to further analyze information on the cellular phenotype and cytokines connected to the disease to provide insights on schistosomiasis and susceptibility to the disease.
Respiratory Syncytial Virus vaccination during pregnancy and effects in infants
In infants, respiratory syncytial virus (RSV) is the primary cause of infections of the lower respiratory tract. To mitigate the phenomenon, a study on the impacts of inoculation against RSV in pregnant women was conducted by the team of Medical Department’s Dr. Joanne De Jesus-Cornejo, who also presented the study.
The participants of the study were healthy pregnant women at 28 weeks to 36 weeks of gestation who were expecting to deliver their infants near the beginning of the RSV season. They were randomly divided into two groups, one would receive a single dose of intramuscular RSV fusion (F) protein nanoparticle vaccine, while the other group would just have a placebo. After birth of their infants, the infants were monitored for 180 days for lower respiratory tract infection and 364 days to monitor safety.
The study shows that those injected with vaccine incurred local injection-site reactions more than those injected with placebo. Meanwhile, percentages for recorded adverse events were similar between both groups. Percentages of the vaccine group for infants with RSV-associated lower respiratory tract infection, RSV-associated lower respiratory tract infection with severe hypoxemia, and hospitalization for RSV-associated lower respiratory tract infection were all lower than those of the placebo group.
Comparison of Rhinovirus A-, B-, and C-associated respiratory tract illness severity based on the 5’-untranslated region among children younger than 5 years
Severe acute respiratory infections among hospitalized children are frequently caused by rhinoviruses (RVs). RVs are further classified as RV-A, RV-B, and RV-C. The study presented by Joanna Ina Manalo of the Molecular Biology Laboratory compared clinical characteristics and severity of respiratory tract illnesses caused by RV and RV-C clades evident in children engaged in hospital settings in rural communities in the country, and children under primary care.
The study utilized clinical samples and gathered information on children in the Philippines from 2014-2016, with ages below five (5). The samples had undergone reverse-transcription PCR (RT-PCR) to target the 5’-untranslated region. Sequenced samples were those RT-PCR confirmed positive samples, while phylogenetic analysis was conducted among RV species.
Through the study, it was recorded that severe respiratory illnesses were more prevalent in children affected by RV-C and GAC1 clade as opposed to those affected with RV-A or RV-B.
After the presentation of the studies, the floor was opened for questions from the audience. RIO’s Dr. Frederick Llanera moderated the open forum, gathering several queries from the participants about all the studies presented. Numerous concepts were tackled during the interactive discussion with the speakers and participants.
The closing remarks were given by the Human Resource Department Head Ms. Ma. Teresa Cristobal on behalf of officer-in-charge Administrative Division Chief Dr. Edison Alberto. According to Ms. Cristobal, “[W]e (RITM) have an approved documented policy for writer’s leave. Pero [kaunti] lang po ang nag-aavail n’on..ito pong writer’s leave na ito [will] provide our researchers protected time to do their research. I think it’s about time that we revisit po the writer’s leave.” This remark was to remind researchers of the writer’s leave privilege.
(To all our researchers, we have an approved documented policy for writer’s leave. But only few avail the aforementioned…this writer’s leave will provide our researchers protected time to do their research. I think it’s about time that we revisit the writer’s leave.)
The Research Forum concluded by noon. After the event, researchers and the speakers gathered into small groups and had further discussions about the studies presented among themselves.
by Anel Azel Dimaano