Abstract
Avidity is consider one of the important and significant manifestations of the humeral immune response to virus covid-19(, representing the binding strength antigen with antibody, in many viral infections low avidity consider risk factor for reinfection. While many of the infected people have mild symptoms or no symptoms, there is a group of patients have strong symptoms and need intensive care. Imbalance in cytokine production is the main mechanism for disease progression, an increase of selected pro-infammatory and anti-infammatory cytokines correlate with severity of disease, Therefore, assessing the level of certain cytokines can give an indication of disease progression and thus provide an accurate protocol of treatment. The purpose of this paper was to study the relation between severity of reinfection and vaccination by compression the values of antibody level and IgG avidity, also measure certain cytokines (IL-10, IL-6, IL-8, IL-7, IL-2, IFN-γ, TNF-α, IL-1β, TGF-β) in vaccinated reinfection patients (with first and second dose) and non-vaccinated reinfection covid-19 patients. Blood samples were pulled in (first, third and sixth) months after infection from 60 reinfection patients with covid-19: 30 patients were vaccinated with first and second dose, they were asymptomatic or show mild symptoms and 30 patients were non-vaccinated they have severity symptoms. The serum were obtained from all patients and evaluated for the Antibody levels, IgG-avidity, also inflammatory and proinflammatory cytokines were analyzed. There are clearly differences in all evaluated parameters were observed when comparing severe (group B non-vaccinated) and mild (group A vaccinated). The vast majority of samples contained s and n-antibodies (82%, 80% respectively in group A n=30 and 80%, 81 respectively in group B n = 30), level of total n-antibodies in group A clearly rises within one to three months (median value: 20.8, 31.2 s/co p<0.001), and clearly decreases significantly through three to six months (median value: 16,1 p<0.001), also in group B the levels increase then decrease (18.3, 22.4,14.8 respectively, P<0.001). there is clearly decrease in the level of (IgG) anti-spike (30.2, 21.4 and 16.2 RU/ml, p<0.001) were in group A also in group B (23.6, 18.4, 15.8 P< 0.001), there were a significant increase in the IgG-avidity index (median values 48.6, 56 and 61%, p<0.001) in group A were observed from (1 to 3 to 6) months also in group B (32.4, 41.2, 49.3 P<0.001), at the same time a significant differences in IgG-avidity index were shown between A and B groups. There was significant differences at (P<0.001 (for all tested cytokines between the group A (vaccinated mild reinfection patients) and group B (non-vaccinated sever reinfection patients), group B had significantly higher serum IL-10, IFN-γ, IL-6, IL-2, IL-1β, IL-8, TGF-β concentrations than group A. But the level of IL-7, TNF-α significantly decrease in group A as compared to group B as shown in (table 6). our results indicates that the vaccination that precedes the infection prepares the body to be a strong immune environment to resist the virus, represented by strength of binding or affinity between antibody and antigen, An inhibitors for some selected cytokines may be a good idea to alter induced hyperinflammation (cytokine storm) then prevent disease progression and dysfunction of many organ that contribute to an increasing mortality of covied-19 patients.