Impact of aging and gender on the lg-containing cell profile of the lacrimal gland

. The present study investigated the influence of age and gender on the number of IgA- and IgM-containing cells in the lacrimal gland. Tissues were obtained from male and female rats at 0.2 (infant), 0.6 (pre-pubertal), 1.3 (pubertal), 3 (adult), 8 (mid-life) and 17 (senescent) months of age, then processed for immunofluorescence microscopy. No IgA-containing cells could be detected in lacrimal glands from infant rats, but a significant accumulation had occurred by 0.6 months of age. The extent of this increase was gender-dependent: tissues from male rats had significantly higher IgA-positive cell densities than those of females. After 0.6 months of age, no further variations in the density of IgA-containing lymphocytes were observed in female gland. In contrast, male glands exhibited marked fluctuations in the density of IgA-containing lymphocytes during the time period spanning puberty (0.6 3 months). Of interest, the frequency distibution of IgA-containing cells in tissue sections was not uniform in rats older than 0.2 months. Correction of cell densities for age-related elevations in lacrimal gland weight demonstrated that the total accumulation of IgA-containing cells was both age- and gender-related. Highest cell numbers were attained at 3 months in females and 3 and 17 months in males. Moreover, at all assessed ages, the total IgA-containing cell number in glands of males was greater than, or equal to, that in tissues of females. In contrast to the IgA-positive cell profile, no age- or gender-associated differences were apparent in the number of IgM-containing cells in the lacrimal gland. These findings demonstrate that both age and gender exert a significant impact on the population of IgA-, but not IgM-, containing cells in lacrimal tissue.