Different groups of mice were immunized with either gram neg

Different groups of mice were immunized with either gram negative bacteria,

Gr. 2, with Mycobacteria Tuberculosis a gram positive bacterium, Gr. 3, and

with the M390 murine virus, Gr. 4. Control unimmunised mice, Gr.1, were

also included in the experiment. Ten days later, You analysed the content of

lymphocyte populations in their spleens and you obtained the following results:

% of : CD4 +ve cells                       CD8 +ve Cells          CD19+ve cells

Gr. 1               24                               11                               32

Gr. 2               20                               7                                  70

Gr. 3               68                               10                               27

Gr.4                14                               79                               25

What can you conclude from the above data on the type of cellsthe immune system uses to fight distinct type of infections?(Please ignore any knowledge that you might have.Derive your conclusions ONLY from the data )

Solution

CD19 is expressed on B cells and follicular dendritic cells.

CD4 is expressed on T helper cells, monocytes, macrophages and dendritic cells.

CD8 is expressed on cytotoxic T-cells, Natural killer cells, cortical thymocytes and dendritic cells.

Gr.1 is not immunized and hence must show normal levels of the lymphocyte cells. All other groups will be compared to this group to determine the effect of immunization on the mice and cells used by their bodies to fight the foreign body.

Gr.2 witnesses a high concentration of CD19+ve cells (70), low CD8 +ve Cells (7) and a normal level of CD4 +ve cells (20) as compared to Gr.1. Hence in case of Gr.2, the body is using B cells and follicular dendritic cells to fight the infection.

Gr. 3 witnesses a high level of CD4 +ve cells (68), normal level of CD8 +ve cells (10) and low levels of CD19 +ve cells(27) as compared to Gr.1. Hence in case of Gr.3, the body is using T helper cells, monocytes, macrophages and dendritic cells to fight the infection.

Gr.4 witnesses a low level of CD4+ve cells (14), high level of CD8 +ve cells(79) and low level of CD19+ve cells(25) as compared to Gr.1. Hence in case of Gr.4, the body is using cytotoxic T-cells, Natural killer cells, cortical thymocytes and dendritic cells to fight the infection.