The cell-mediated immune response to HIV-1 is an essential element of the mechanisms for viral replication control. Currently, most of the vaccine candidates in clinical trials were developed to stimulate HIV-1-specific CD8+ cytotoxic (CTL) and CD4+ T helper (Th) lymphocytes. We have been working on a novel approach to develop a vaccine formulation for HIV-1 using a recombinant multiepitopic protein (named CR3), which comprises CTL and Th epitoperich regions of HIV-1 from several subtype B isolates, co-inoculated with the hepatitis B virus surface (HBsAg) and core (HBcAg) antigens of the hepatitis B virus (HBV) as adjuvant. According to our studies in mice, the nasal-subcutaneous co-administration of this multiantigenic formulation induces a strong Th1-biased specific response against CR3, CD8+ T cells in mice spleen and IFN-γ-secreting cells in mesenteric lymph nodes. Cross-reactive p24-specific IFN-γ-secreting cells in spleen were also detected. Moreover, Nef-specific antibodies were elicited in mice sera which might avoid the toxic effects of this antigen. However, a marginal anti-CR3 antibody response was elicited in vaginal mucosa. Additionally, we observed anti-HBsAg and anti-HBcAg cellular and humoral responses. In this regard, our multiantigenic formulation might provide immunity against HBV as an additional benefic considering the high HIV-1-HBV co-infection rate reported worldwide.
Cockroaches serve as mechanical vectors for medically important pathogens, and their presence in hospitals is a common occurrence. This review summarizes the pathogens carried by cockroaches collected in hospitals around the world during the period 2000–2024 and focuses on their antibiotic resistance mechanisms and potential impact on the public health system. The conventional techniques are most used to identify microorganisms and determine antibiotic resistance, but there are few studies that use molecular techniques for bacterial identification and resistance mechanism detection. The species that appear most frequently in the selected articles were Escherichia coli (22 articles) and Pseudomonas aeruginosa (11 articles). Regarding antibiotic resistance, this review describes 79.0% (34/43) of the studies analyzed. E. coli and P. aeruginosa bacteria were found to be resistant to antibiotics in 51.2% and 25.6% of articles, respectively. The identification of pathogens carried by cockroaches collected in hospitals suggests a potential risk of these insects in the transmission of healthcare-associated infections, mainly in developing countries, where this issue is most alarming. The collected data suggest that integrated approaches to cockroach control and infestation management should be put in place based on scientific evidence.
Several adjuvants have been described and tested in humans. However, the aluminum-based adjuvants remain the most widely used component in vaccines today. Emerging data suggest that aluminum phosphate and aluminum hydroxide adjuvants do not promote a strong commitment to the helper T cell type 2 (Th2) pathway when they are coadministered with some Th1 adjuvants. In this regard, subtle differences between both aluminum-based adjuvants have been demonstrated. We have previously shown that subcutaneous immunization, in aluminum phosphate, of a mixture comprising the surface and core antigens of hepatitis B virus (HBV) and the multiepitopic protein CR3 of human immunodeficiency virus type 1 elicits a CR3-specific Th1 immune response. In these experiments, the antigens were adjuvated at the same time. As the final selection of the best adjuvant should be based on experimental evidence, we asked whether aluminum hydroxide allows a better Th1 immune deviation than aluminum phosphate. We also studied several ways to mix the antigens and the impact on CR3-specific interferon (IFN)-γ secretion. Our findings indicate that aluminum hydroxide allows better Th1 immunodeviation than aluminum phosphate adjuvant for the mixture of HBV antigens and CR3. In addition, CR3-specific IFN-γ secretion of the various formulations tested was the same irrespective of the order in which the antigens were combined.