case_images: PMC11251942_01
case_images: Radiological findings in a patient with RRMS after treatment with alemtuzumab. (A, B) Brain MRI obtained 11 months after the first cycle. Post-contrast T1 images showed new gadolinium-enhancing lesions, some of them with open-ring enhancement. (C, D) Brain MRI conducted 24 months after the second cycle revealed several new demyelinating lesions on FLAIR images (C), some of them showing large morphology with closed-ring enhancement located in the left frontal opercular juxtacortical white matter (maximum diameter 21 mm) and bilateral parietal subcortical white matter (D). (E, F) Brain MRI conducted 2 months later revealed an increased size of the lesion in right corona radiata (maximum diameter 25 mm) with closed-ring enhancement, perilesional edema and mild mass effect on the right lateral ventricle, and also a reduction in the size of the left frontal and bilateral parietal lesions with resolution of contrast enhancement. (G, H) After 3 months of natalizumab treatment, brain MRI illustrated a remarkable reduction in lesion size on FLAIR images (G) with complete resolution of the contrast enhancement (H). MRI: Magnetic resonance imaging, RRMS: relapsing-remitting multiple sclerosis. FLAIR: Fluid-attenuated inversion recovery.
case_images: fimmu-15-1395749-g001.jpg
case_images: PMC11251942_01_fimmu-15-1395749-g001.jpg
case_images: f1
case_images: A brain MRI conducted 2 months later revealed 12 new T1Gd +  lesions ( Figures 1A, B ). The brain MRI revealed multiple new T1Gd +  demyelinating lesions, including multiple TDLs with closed-ring enhancement, perilesional edema and mass effect on the lateral ventricles ( Figures 1C, D ). Given the appearance of new TDLs in a routine MRI scan after 2 months ( Figures 1E, F ), she underwent MP treatment again and natalizumab was initiated (JC virus negative). After 3 months of natalizumab treatment, the size and enhancement of TDLs diminished ( Figures 1G, H ).
case_images: Longitudinal dynamics in the percentage of the lymphocyte subpopulations in the peripheral blood by flow cytometry during alemtuzumab treatment in the patient. Between 8 and 10 months after the first cycle of alemtuzumab, at the same time as the mild sensory event and the multiple gadolinium-enhancing Gd+ lesions appearance, we observed an increase in the percentage of total B lymphocytes (A) and a decrease in the percentage of total T lymphocytes (B) in peripheral blood. Together with the appearance of the tumefactive demyelinating lesions, we observed an increase in the percentage of total B lymphocytes (A) and, regarding the Th1 memory cells (C, D), an increase in the percentage of Th1 central memory cells (C). Three months before, an increase in the percentage of Th1/Th17 cells was observed (E, F).
case_images: fimmu-15-1395749-g002.jpg
case_images: PMC11251942_01_fimmu-15-1395749-g002.jpg
case_images: f2
case_images: An increase in the percentage and absolute counts of total B-cell populations ( Figures 2A ,  3A ) was detected in peripheral blood at the time of this sensory event, coupled with a decrease in the percentage of total T-cell populations ( Figure 2B ). IgG/albumin index and OGB were similar to those at the time of diagnosis. In peripheral blood, we found again a rise in the percentage and absolute counts of B-cells ( Figures 2A ,  3A ), as well as an increase in the absolute counts of T-cells ( Figure 3B ). Th1 memory cells ( Figures 2C, D ,  3C, D ), an increase in the percentage and absolute counts of Th1 central memory cells was observed ( Figures 2C ,  3C ). Transitional B-cells, defined as CD19+CD27-CD24hiCD38hi, were analyzed with no differences. In contrast, an increase in the percentage and absolute counts of Th1/Th17 cells ( Figures 2E, F ,  3E, F ), specially central memory ( Figures 2E ,  3E ), was detected 3 months prior to the TDLs detection.
case_images: Longitudinal dynamics in absolute counts of lymphocyte subpopulations in the peripheral blood by flow cytometry during alemtuzumab treatment in the patient. Between 8 and 10 months after the first cycle of alemtuzumab, at the same time as the mild sensory event and the multiple gadolinium-enhancing Gd+ lesions appearance, we observed an increase in the absolute counts of total B lymphocytes (A) in peripheral blood. Together with the appearance of the tumefactive demyelinating lesions, we observed an increase in the absolute counts of total B and T lymphocytes (A, B) and an increase in the absolute counts of Th1 memory cells (C, D), specially Th1 central memory cells (C). Three months before, an increase in the absolute counts of Th1/Th17 cells was observed (E, F).
case_images: fimmu-15-1395749-g003.jpg
case_images: PMC11251942_01_fimmu-15-1395749-g003.jpg
case_images: f3
case_images: An increase in the percentage and absolute counts of total B-cell populations ( Figures 2A ,  3A ) was detected in peripheral blood at the time of this sensory event, coupled with a decrease in the percentage of total T-cell populations ( Figure 2B ). IgG/albumin index and OGB were similar to those at the time of diagnosis. In peripheral blood, we found again a rise in the percentage and absolute counts of B-cells ( Figures 2A ,  3A ), as well as an increase in the absolute counts of T-cells ( Figure 3B ). Th1 memory cells ( Figures 2C, D ,  3C, D ), an increase in the percentage and absolute counts of Th1 central memory cells was observed ( Figures 2C ,  3C ). Transitional B-cells, defined as CD19+CD27-CD24hiCD38hi, were analyzed with no differences. In contrast, an increase in the percentage and absolute counts of Th1/Th17 cells ( Figures 2E, F ,  3E, F ), specially central memory ( Figures 2E ,  3E ), was detected 3 months prior to the TDLs detection.