Influence of whole human milk, and fractions thereof, on inclusion‐formation of Chlamydia trachomatis in McCoy cells

Abstract

A study of the effect of human breast milk, and components thereof, on the capacity of Chlamydia trachomatis to form inclusions in cycloheximide‐treated McCoy cells, was undertaken. Pooled whole milk collected during the first week of breast feeding caused a concentration‐dependent inhibition of the chlamydial inclusion‐formation. The activity resided in the fat and fat globule membrane (FGM) components of the milk. The active principle in the FGM fraction is heat‐stable and pronase‐sensitive, but resistant to both neuraminidase and periodate. Immunoglobulins was not responsible for the inhibition. Whey and casein fractions of milk increased the chlamydial inclusion‐formation. The activity of the whey was heat‐stable, dose‐related, and had a mol.wt. of 12,000. The casein fraction was still active after heat treatment. Whey samples collected up to 28 days after delivery varied slightly in their stimulatory activity, with an optimum between the 7th and 14th days. The present study demonstrated a multieffect of breast milk on chlamydial inclusion‐formation: an inhibitory activity due to a protein compound as well as another factor in the fat fraction and an enhancing effect due to a heat‐stable factor(s).

Killing of Chlamydia trachomatis by Novel Antimicrobial Lipids Adapted from Compounds in Human Breast Milk

“…Even though C. trachomatis is an obligate intracellular bacterium, the elementary body (EB) or infectious form of the organism is found extracellularly in secretions. EBs are adapted for survival in cell-free conditions but are susceptible in vitro to various antimicrobials such as detergents (7), peptides (11), whole human milk, and fractions of it (2). We undertook these studies to examine whether genital strains of C. trachomatis were killed by these novel antimicrobial lipids adapted from human breast milk.…”