Age-related decline in the antibody response to E. coli lipopolysaccharide in New Zealand Black mice.

A thymus-independent immune function in ageing NZB and BALB/c mice was compared by measuring the antibody response to E. coli lipopolysaccharide (LPS). Since it was found that 10-13 month-old NZB mice was particularly sensitive to LPS, this antigen had to be detoxified by alkali treatment. The anti-LPS splenic plaque-forming cell (PFC) response of NZB mice decreases with age and was lower than that of BALB/c mice in all age groups studied. The response of 4- and 10-month-old NZB mice showed an irregular time course and a number of mice showed no response. The present results indicate that, besides an impairment of T-cell functions, an impairment on the B-cell level must also be considered in ageing NZB mice.