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The anti-spike T cell and antibody responses to SARS-CoV-2 mRNA vaccines in patients with B-cell malignancies were examined in a real-world setting. An NGS-based molecular assay was used to assess SARS-CoV-2-specific T cell responses. After the second dose, 58% (166/284) of sero-positive and 45% (99/221) of sero-negative patients display anti-spike T-cells. The percentage of patients who displayed T cell response was higher among patients receiving mRNA-1273 vaccines compared to those receiving BNT162b2 vaccines. After the third vaccination, 40% (137/342) of patients seroconverted although only 22% displayed sufficient antibody levels associated with the production of neutralizing antibodies. 97% (717/738) of patients who were sero-positive before the third dose had markedly elevated anti-spike antibody levels. Anti-spike antibody levels, but not T-cell responses, were depressed by B cell-directed therapies. Vaccinated patients with B cell malignancies with a poor response to SARS-CoV-2 vaccines may remain vulnerable to COVID-19 infections.

Expression of resistance to erythromycin in Escherichia coli, caused by an altered L4 protein in the 50S ribosomal subunit, can be masked when two additional ribosomal mutations affecting the 30S proteins S5 and S12 are introduced into the strain (Saltzman, Brown, and Apriion, 1974). Ribosomes from such strains bind erythromycin to the same extent as ribosomes from erythromycin sensitive parental strains (Apirion and Saltzman, 1974). Among mutants isolated for the reappearance of erythromycin resistance, kasugamycin resistant mutants were found. One such mutant was analysed and found to be due to undermethylation of the rRNA. The ribosomes of this strain do not bind erythromycin, thus there is a complete correlation between phenotype of cells with respect to erythromycin resistance and binding of erythromycin to ribosomes. Furthermore, by separating the ribosomal subunits we showed that 50S ribosomes bind or do not bind erythromycin according to their L4 protein; 50S with normal L4 bind and 50S with altered L4 do not bind erythromycin. However, the 30S ribosomes with altered S5 and S12 can restore binding in resistant 50S ribosomes while the 30S ribosomes in which the rRNA also became undermethylated did not allow erythromycin binding to occur. Thus, evidence for an intimate functional relationship between 30S and 50S ribosomal elements in the function of the ribosome could be demonstrated. These functional interrelationships concerns four ribosomal components, two proteins from the 30S ribosomal subunit, S5, and S12, one protein from the 50S subunit L4, and 16S rRNA.

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