Immunological aspects of vaccination in HIV-infected patients

Until recently, HIV infection does not lose its relevance. In 2022, 630 000 people died and 1.3 million people became infected with the human immunodeficiency virus (HIV). HIV-positive persons develop more infectious diseases than healthy people do; the causative agents are mainly opportunistic microorganisms. Streptococcus pneumoniae is the main causative agent of infection in the lungs in HIV-infected persons. In order to prevent the development of severe pneumococcal infections and to overcome antibiotic resistance, vaccines have been developed. There are polysaccharide (PPV) and conjugate (PCV) vaccines. According to clinical recommendations, vaccination of previously unvaccinated HIV-infected patients is carried out regardless of T-helper cell level. However, no data were found on the effect of PCV13 on immunological memory cells. The purpose of this study is to assess an effect of PCV13 vaccination on the immune system in HIV-infected subjects.

Materials and methods. The study included 200 patients with HIV infection, which were divided into two groups: I — received a dose of PCV13 (n = 100) and control group (n = 100). During the first visit, immunological and microbiological studies were carried out. On the second visit, a PCV13 was injected into the deltoid muscle. The third visit was made a year later, where immunological and microbiological studies were repeated. Participants were divided into 4 subgroups depending on CD4⁺ T cell level. The microbial study was done using a swab collected from the back of the throat.

Results. During the immunological examination at visit 1, abnormalities were detected in all examined populations and immune cell subsets. At 12 months post-vaccination, the median levels of CD3⁺CD4⁺ and CD45^RO+ T lymphocytes in the immunized group were higher than pre-vaccination levels compared to control group, in which the values changed insignificantly. Our data confirm the immunological effectiveness of PCV13 administration in HIV-infected patients. In patients with peripheral blood CD19⁺ lymphocyte deficiency, had increased microbial detection rate (p = 0.003).

Conclusion. As a result, due to the high risk of pneumococcal pneumonia, HIV-infected patients should be immunized with a 13-valent pneumococcal conjugate vaccine.