HIV Epidemic Among Men Who Have Sex with Men (MSM) and Transgender Women (TGW) in Sarawak, Malaysia: An analysis from the Integrated Biological and Behavioural Surveillance (IBBS) Lite 2024 Introduction Men who have sex with men (MSM) and transgender women (TGW) are among the key populations affected by the HIV epidemic in Sarawak, Malaysia. The objective of this study was to determine HIV prevalence and associated behaviour among MSM and TGW in Sarawak. Methods Respondent-driven sampling (RDS) was used to recruit MSM and TGW between June and August 2024. The study consisted of two components. The first component was a behavioural survey, conducted through a selfadministered online questionnaire via a web-based platform. The second component involved biological testing, where respondents were instructed to visit a community-based testing site of their choice for blood testing after completing the online survey. Statistical analysis was performed in RStudio using the Gile's Successive Sampling Estimator. Results This study recruited 217 MSM and 151 TGW. Consistent condom use among both groups remains low. While most MSM and TGW reported recent HIV testing, Hepatitis C testing and treatment rates are still low. HIV prevalence in Sarawak was 9.5% (95% CI: 2.9, 16.0) among MSM and 10.1% (95% CI: 1.8, 18.5) among TGW, with syphilis prevalence among MSM reaching a concerning 12% (95% CI: 1.8, 22.3). Conclusions In conclusion, improving HIV prevention and care for MSM and TGW in Sarawak requires promoting condom use, increasing awareness of Hepatitis C, and including substance use interventions in HIV programs. Community outreach using culturally sensitive approaches is crucial to improving access to services and building trust. Furthermore, integrating syphilis management into HIV prevention efforts is critical, given its strong association with increased HIV risk. Findings highlight the need for targeted interventions and continued surveillance among key populations in Sarawak to ensure a sustained and effective public health response.

OBJECTIVETo characterize the major allergens of Macrobrachium rosenbergii (giant freshwater prawn).

METHODSRaw and cooked extracts of the giant freshwater prawn were prepared. The IgE reactivity pattern was identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting technique with the sera of 20 skin prick test (SPT) positive patients. The major allergen identified was then characterized using the proteomics approach involving a combination of two-dimensional (2-DE) electrophoresis, mass spectrometry and bioinformatics tools.

RESULTSSDS-PAGE of the raw extract showed 23 protein bands (15-250 kDa) but those ranging from 40 to 100 kDa were not found in the cooked extract. From immunoblotting experiments, raw and cooked extracts demonstrated 11 and 5 IgE-binding proteins, respectively, with a molecular mass ranging from 15 to 155 kDa. A heat-resistant 36 kDa protein was identified as the major allergen of both extracts. In addition, a 42 kDa heat-sensitive protein was shown to be a major allergen of the raw extract. The 2-DE gel fractionated the prawn proteins to more than 50 different protein spots. Of these, 10 spots showed specific IgE reactivity with patients' sera. Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis led to identification of 2 important allergens, tropomyosin and arginine kinase.

CONCLUSIONSIt can be concluded that the availability of such allergens would help in component-based diagnosis and therapy of prawn allergies.

Allergens ; isolation & purification ; Animals ; Computational Biology ; Electrophoresis, Gel, Two-Dimensional ; Electrophoresis, Polyacrylamide Gel ; Fresh Water ; Humans ; Immunoblotting ; Immunoglobulin E ; immunology ; Mass Spectrometry ; Molecular Weight ; Palaemonidae ; chemistry

Objective To characterize the major allergens of Macrobrachium rosenbergii (giant freshwater prawn). Methods Raw and cooked extracts of the giant freshwater prawn were prepared. The IgE reactivity pattern was identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting technique with the sera of 20 skin prick test (SPT) positive patients. The major allergen identified was then characterized using the proteomics approach involving a combination of two-dimensional (2-DE) electrophoresis, mass spectrometry and bioinformatics tools. Results SDS-PAGE of the raw extract showed 23 protein bands (15-250 kDa) but those ranging from 40 to 100 kDa were not found in the cooked extract. From immunoblotting experiments, raw and cooked extracts demonstrated 11 and 5 IgE-binding proteins, respectively, with a molecular mass ranging from 15 to 155 kDa. A heat-resistant 36 kDa protein was identified as the major allergen of both extracts. In addition, a 42 kDa heat-sensitive protein was shown to be a major allergen of the raw extract. The 2-DE gel fractionated the prawn proteins to more than 50 different protein spots. Of these, 10 spots showed specific IgE reactivity with patients' sera. Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis led to identification of 2 important allergens, tropomyosin and arginine kinase. Conclusions It can be concluded that the availability of such allergens would help in component-based diagnosis and therapy of prawn allergies.

Background: Prawns and shrimp are a frequent cause of seafood allergy mediated by IgE antibodies. Penaeus monodon and Penaeus latisulcatus, commonly known as black tiger prawn and king prawn, respectively, are among the most frequently consumed prawns in Malaysia. The aim of thi s study was to identify the IgE-binding proteins of these 2 prawn species. Methods: Raw and boiled prawn extracts were prepared and then resolved by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). IgE-immunoblotting was then performed using sera from patients with positive skin prick tests to the raw prawn extracts. Results: SDS-PAGE analysis of the raw extracts of both prawn species revealed 23 protein bands; the boiled extracts yielded fewer protein bands. The bands in the range of 40 to 100 kDa were sensitive to heat and therefore were not found in the boiled extracts. Immunoblot of raw extracts of black tiger prawns and king prawns yielded 14 and 11 IgE-binding proteins, respectively, with molecular weights of between 15 and 200 kDa. Proteins at 36, 42, and 49 kDa were detected as the major allergens in both species of prawns. A protein of 75 kDa was also identified as a major allergen in black tiger prawns. Other potential allergens were also observed at various molecular masses. Conclusion: Proteins of 36, 42, and 49 kDa were identified as the major allergens of both species of prawns. The 36 and 42 kDa proteins are hypothesised to be tropomyosin and arginine kinase, respectively. A high molecular weight protein of 75 kDa was found to be an additional major allergen in black tiger prawns.