Corrigendum: Factors Predicting the Presence of Maternal Cells in Cord Blood and Associated Changes in Immune Cell Composition

[This corrects the article DOI: 10.3389/fimmu.2021.651399.].

In the original article, there was a mistake in the legend for Figure 1 as published. The value of MMc in WB for CB#45 indicated in the legend of Figure 1 corresponded to the value of MMc (305 gEq) per number of host cells tested per experiment (~246, 000 gEq), not per million of host cells. The correct legend appears below.
The correct legend appears below Figure 1.
In the original article, there was a mistake in the legend for Figure 3B as published. As the values of MMc in WB indicated corresponded to the values of MMc per number of host cells tested per experiment (mean~212,360 gEq ±31,110), not per million of host cells, this results in minimal changes in the p value. Moreover the symbols "inferior or equal to" or "superior to" did not appear correctly, they are spelled out in the corrected legend. The correct legend appears below.
The correct legend appears below Figure 3.  there is a greater feto-maternal HLA-A and/or DRB1 compatibility from the child's perspective. Cord blood samples are separated into negative, slightly positive, moderately positive or highly positive for MMc. Slightly positive samples had a mean of MMc per subset tested inferior or equal to 10gEq/106, moderately positive samples had a mean of MMc per subset tested comprised between 10 and 100 gEq/106 and highly positive samples a mean superior to 100gEq/106. The frequency of HLA-A and/or DR compatible (in red) or incompatible (in grey) CB samples from the child's perspective is calculated in each group. P value is calculated by comparing compatibility frequencies between negative and the three categories positive samples (P= 0.002, Two-tailed Fisher's test, 2x4).
In the original article, there was a mistake in Figure 1  In the original article, there was a mistake in Figure 3B as published. Consequent to the initial mistake where values of MMc in WB were given per number of host cells tested per experiment instead of MMc per million of host cells, instead of having 11 cord blood (CB) samples with MMc ≤10 gEq, six between 10-100 gEq and four with > 100 gEq, respectively N=9, N=7 and N=5 CB corresponded to each category. Results are extremely similar to previously published data and similarly significant (P=0.002). The corrected Figure 3B appears below.
In the original article, there was an error in Patients and Methods, Statistics, paragraph 2 as published: "The number of maternal cells per million of CB cells found per subset was added up for all the subsets and divided by the number of subsets tested, giving mean values of total MMc per CB ranging from 0.3 to 744 gEq/ 10 6 ". The values of MMc in WB indicated in the text corresponded to the values of MMc per number of host cells tested per experiment (mean~212,360 gEq ±31,110), not per million of host cells.
A correction has been made to the text as follows: "The number of maternal cells per million of CB cells found per subset was added up for all the subsets and divided by the number of subsets tested, giving mean values of total MMc per CB ranging from 0.3 to 818 gEq/10 6 ." In the original article, there was an error in Results, paragraph 3 as published: "Among the 30 samples positive for MMc, four had high quantities of MMc in whole blood comprised between 110 and 305 gEq/10 6 of cord blood cells (75th percentile of positive values)".
A correction has been made to the text as follows: "Among the 30 samples positive for MMc, four had high quantities of MMc in whole blood comprised between 226 and 1240 gEq/10 6 of cord blood cells."